JP6044628B2 - Random number generation device, random number generation method, object placement device, and computer program - Google Patents

Description

  The present invention relates to a technical field of calculation processing for generating pseudo-random numbers having specific properties.

  For example, random numbers are often required in calculation processing using a computer (information processing apparatus). When a random number is generated by a device, a specific operation is performed by using the original data (hereinafter may be referred to as “object” or “object data”) by a device such as a computer or a dedicated arithmetic circuit. As a result, the device generates a pseudo random number. In the present application, such a device is referred to as a “pseudo random number generator”, and in the following description, a pseudo random number generated by such a device may be simply referred to as a “random number”.

  The pseudo-random number generator generates the same numerical sequence when generated using the same original data, while the numerical sequences that are not substantially related to each other when the original data are different. There are pseudo-random number generators that have the property of being generated. Such pseudo random number generators are widely used in various fields. Examples of the pseudorandom number generator having such properties include the techniques described in Patent Document 1 and Patent Document 2.

  FIG. 10 is a diagram illustrating the procedure of the method described in Patent Document 1. The pseudo random number generation method described in Patent Document 1 discloses a method of generating a pseudo random number (pseudo random number sequence) based on known object data.

  That is, in the iterative processing procedure shown in FIG. 10, first, in iteration step 1, the start value S0 is received, and the key K0 is calculated based on the start value S0.

  In the iteration step 2, the one-way function f is applied to the start value S0 and the key K0 calculated in the iteration step 1. The calculation result of the one-way function f in the iteration step 2 is represented by f (S0, K0).

  In the iteration step 3, the calculation result f (S0, K0) obtained in the iteration step 2 is decomposed into three values (S1, K1, R1). Of these three values, S1 is treated as an initial value for the next calculation by the one-way function f, and K1 is treated as a key (repetition step 4). R1 is treated as the first part of the pseudorandom number generated by the series of iterative processes shown in FIG.

  In the iteration step 5, an operation is performed by the one-way function f using S1 and K1 in the iteration step 4, and f (S1, K1) as a result of the operation is obtained. In the iteration step 6, as in the iteration step 2, the calculation result f (S1, K1) is decomposed into three values (S2, K2, R2).

  That is, in the method described in Patent Document 1, the above-described series of iterative processes is repeated a predetermined number of times, and thereafter, pseudorandom numbers such as R1, R2,. As a result, a pseudo-random number is finally obtained. As described above, according to the method described in Patent Document 1, it is possible to generate a random number sequence in a pseudo manner using known object data.

  Patent Document 2 discloses a technique for generating a large number of binary patterns excellent in randomness as a pseudo-random number sequence by a pseudo-random number generation circuit in which a register and a logic circuit are combined. .

Special table 2009-512930 JP 09-282146 A

  By the way, in the method disclosed in Patent Document 1, for example, the range of the value of the random number generated by the pseudo-random number generator (hereinafter, referred to as “value range that the random number sequence can take” or “value range of the random number sequence” may be abbreviated). ) Is changed. In this case, among the random number values included in the random number sequence generated after the change, the random number values that are also included in the range of random numbers generated before the change are generated by the pseudo random number generator before the change. The order of random numbers to be performed is not limited, and the random number value included in the random number sequence before the change is not necessarily taken.

  Therefore, even if the range that can be taken by the generated random number sequence is changed, the present invention is included in the range that can be taken by the random number sequence that is generated before the change among the random number values that are included in the changed random number sequence. Random number generator, random number generation method, object placement apparatus, and computer program for maintaining the order of random numbers generated before the change and taking the random number value included in the random number sequence before the change The main purpose is to provide

  In order to achieve the above object, a random number generation device according to the present invention has the following configuration.

  In other words, the random number generation device according to the present invention can generate the same random number sequence based on the same information that is the source of the random number, and can generate a plurality of types of random number sequences having different value ranges that the generated random number sequence can take. The random number included in the range that can be taken by the random number sequence of interest is included in the range that can be taken by the other random number sequence when there is a relationship that is included in the range that can be taken by another random number sequence different from that range. And the random number of the other random number sequence included in a range that can be taken by the focused random number sequence have the same value, and the random number sequence to be generated by the device itself Appearing in the same order.

An object placement device as another aspect of the present invention is:
A random number generator having the above-described configuration;
Arrangement of an object as a partial space of a space representing a range of values that can be taken by the plurality of types of random number sequences using random numbers generated by the random number generator based on information unique to the object And arrangement means for determining by referring to the correspondence information to which the destination is assigned.

Moreover, the random number generation method as still another aspect of the present invention is:
Random number of interest using random number generation means that generates the same random number sequence based on the same information that is the source of the random number and that can generate multiple types of random number sequences that can be taken from different ranges. When the random number included in the range that can be taken by the sequence is in a relationship that is included in the range that can be taken by another random number sequence different from the range, the relationship that is included in the range that can be taken by the other random number sequence The random number of the random number sequence of interest and the random number of the other random number sequence included in the range that can be taken by the focused random number sequence have the same value and appear in the same order in the random number sequence to be generated It is characterized by.

  This object is also achieved by a computer program for realizing the random number generation device having the above-described configuration or a corresponding method by a computer, and a computer-readable storage medium storing the computer program.

  According to the present invention, even if the range of values that can be taken by the generated random number sequence is changed, among the random number values included in the changed random number sequence, the range of values that can be taken by the random number sequence generated before the change is included. The random number value to be maintained maintains the order of the random numbers generated before the change, and the provision of a random number generator or the like that takes the random number value included in the random number sequence before the change is realized.

1 is a block diagram illustrating a configuration of a random number generation device (pseudorandom number generation device) according to a first exemplary embodiment of the present invention. It is a block diagram which shows the structure of the random number generator in exemplary 2nd Embodiment of this invention. It is a figure explaining the relationship between the range of the random number sequence which the sub-random number generation function 102 in 2nd Embodiment produces | generates, and the random number which the random number selection function 103 selects. It is a flowchart showing operation | movement of the random number selection function 103 which concerns on the 2nd Embodiment of this invention. It is a figure which shows an example of the hardware constitutions of the information processing apparatus 1000 which can implement | achieve the random number generator which concerns on each embodiment of this invention. It is a figure which illustrates notionally the hardware constitutions of the object arrangement | positioning apparatus 500 in the Example which concerns on the 1st and 2nd Embodiment of this invention. It is a figure which shows the example which represented the storage capacity of the some storage node in the Example which concerns on the 1st and 2nd Embodiment of this invention as a partial space in one-dimensional space. It is a figure showing the correspondence table 300 of the partial space and storage node in the Example which concerns on the 1st and 2nd Embodiment of this invention. It is a figure which shows the example which represented the storage capacity of the storage node in the Example which concerns on the 1st and 2nd Embodiment of this invention as a partial space in a two-dimensional space. It is a figure explaining the procedure of the method described in patent document 1. FIG.

  Next, exemplary embodiments of the present invention and examples thereof will be described in detail with reference to the drawings.

<First Embodiment>
FIG. 1 is a block diagram showing the configuration of a random number generation device (pseudorandom number generation device) according to a first exemplary embodiment of the present invention. The concept common to the embodiments and examples described below is shown in FIG. Represent.

  In FIG. 1, the random number generation device 10 has a random number generation function 12. The random number generation function 12 has a function of generating a random number (pseudorandom number) as described below based on seed information (initial value) 14 given from the outside, and outputting the generated random number 16. The random number range information 15 is a range of values that can be taken by the random number sequence generated by the random number generation function 12 (hereinafter, abbreviated as “range of random number sequence”) from outside the random number generation device 10 (random number generation function 10). 12) information to be specified. The random number range information 15 is set in the random number generator 10 by a user using the random number generator 10 using an appropriate UI (user interface) or by an external device via a communication line (not shown). May be.

  Here, if the random number range information (information indicating the range of the random number sequence) 15 is information that can represent a specific numerical range, for example, the entity of the information is not limited in this embodiment. For example, in the case of an object placement apparatus 500 described later with reference to FIG. 6, the random number range information 15 is used when the remaining capacity (free space) that can be stored by the object placement destination has decreased, The data is supplied to the random number generation device 10 when a system specification change such as deletion of a destination or addition of a new placement destination occurs.

  In this embodiment, the random number generation device 10 (random number generation function 12) performs the following function.

  The random number generation function 12 can generate the same random number sequence when the same information that is the basis of a random number (that is, a pseudo random number) is given as a seed (initial value). Further, the random number generation function 12 can generate a plurality of types of random number sequences having different ranges of the generated random number sequence based on the random number range information 15.

  It should be noted that a general method can be employed for the procedure itself for calculating individual random number sequences in the present embodiment, and a detailed description thereof will be omitted.

  The random number generation function 12 can determine whether or not the random number A included in the range of the random number sequence of interest is in a relationship included in the range of another random number sequence different from the range.

  If the random number generation function 12 determines that the relationship is established by the above determination, the random number A (the random number of the random number sequence of interest) that is included in the range of the other random number sequence and the random number of interest A random number sequence (random number 16) that has the same value as the random number B of the other random number sequence included in the range of the sequence and appears in the same order in the random number sequence to be generated by the random number generation device 10 is output. .

  According to such a random number generation device 10, even if the range of the random number sequence to be generated is changed according to the random number range information 15, out of the random number values included in the changed random number sequence The random number value included in the range of the random number sequence generated before the change is the value of the random number included in the random number sequence before the change while maintaining the order of the random numbers generated before the change.

  In the present embodiment, the random number sequence is not limited to a numeric value sequence, and for example, various types of sequences made up of characters, identifiers, bit sequences, coordinates, etc. can be adopted (in the following embodiments) Is the same).

<Second Embodiment>
Next, a second embodiment based on the random number generation device according to the first embodiment described above will be described. In the following description, characteristic portions according to the present embodiment will be mainly described, and a duplicate description of the same configuration as that of the first embodiment will be omitted.

  FIG. 2 is a block diagram showing a configuration of a random number generation device according to the second exemplary embodiment of the present invention.

  The random number generation device 100 includes a seed providing function 101, a plurality of sub-random number generation functions 102, and a random number selection function 103. The random number generation device 100 is a device that generates a random number 106 based on the input seed information 104a. The value of the random number 106 is included in the random number sequence generated after the change even if the range of the random number sequence generated by the random number generation device 100 is changed according to the seed information 104a, and before the change. The random number value included in the range of the random number sequence generated by the own device is a value that maintains the order of the random number values generated by the own device before the change even after the change.

  The seed providing function 101 generates a seed (seed information) 104b to be set in each sub-random number generation function 102 based on the seed information 104a received from the outside. That is, the seed providing function 101 generates seed information 104b including a plurality of types of seeds that satisfy a predetermined relationship in response to obtaining a certain value as the seed information 104a. This predetermined relationship may be determined by, for example, a function or a table so that different seed information 104b is generated for each individual sub-random number generation function 102. In this case, the seed providing function 101 generates different seed information 104b for each individual sub-random number generation function 102 using such a function or table based on the seed information 104a.

  Then, the seed providing function 101 sets the generated seed information 104b in the individual sub-random number generation function 102. That is, in the present embodiment, the seed providing function 101 provides the same seed 104b with the same content to the same sub-random number generation function 102 if the input seed information 104a is the same.

  The sub-random number generation function 102 generates a random number based on the seed information 104b received from the seed provision function 101. If the received seed information 104b is the same, the sub random number generation function 102 generates the same random number sequence. Since a general technique can be used for the random number generation procedure itself by the sub-random number generation function 102, detailed description in this embodiment will be omitted.

  However, in this embodiment, each sub-random number generation function 102 shown in FIG. 2 has a different range of generated random number sequences. Here, the information regarding the different value ranges, for example, the result generated by the random number selection function 103 or the seed provision function 101 in accordance with the random number range information 105 set from the outside is sent to the individual sub-random number generation function 102. On the other hand, a configuration set by the random number selection function 103 or the seed provision function 101 can be assumed. Alternatively, the random number range information 105 itself may include a range to be specified for the individual sub-random number generation function 102.

  As described above, the plurality of sub-random number generation functions 102 according to the present embodiment have different ranges of generated random number sequences, and the sub-random number generation function B (first sub-random number generation function 102) is generated. The range of the random number sequence includes (includes) the range of the random number sequence by the sub-random number generation function A (second sub-random number generation function 102) in which the range of the generated random number sequence is narrower than that of the sub-random number generation function B. This relationship is shown in FIG.

  FIG. 3 is a diagram illustrating the relationship between the range of the random number sequence generated by the individual sub-random number generation function 102 and the random number selected by the random number selection function 103 in the second embodiment. In FIG. 3, the range related to the sub-random number generation function B is a real number from −1 to 8. On the other hand, the range related to the sub-random number generation function A is a real number from 0 to 4. When there is such a relationship, the random number selection function 103 selects a random number generated by the sub-random number generation function A in a range where the value ranges related to the two sub-random number generation functions (A and B) overlap. Then, the random number selection function 103 selects a random number generated by the sub-random number generation function B in a range in which the ranges related to the two sub-random number generation functions (A and B) do not overlap.

  Here, to generalize the above relationship, in other words, the random number selection function 103 generates the specific sub-random number generated by the specific sub-random number generation function 102 among the plurality of sub-random number generation functions 102. It is determined whether or not the relationship is included in the range of another random number sequence that is narrower than the range of the random number sequence generated by the function 102.

  If the random number selection function 103 determines that the relationship is established in the determination, the random number selection function 103 determines whether the relationship is established or not, among other random number sequences having the narrow range, the range of the random number sequence of interest. Next, another random number sequence that can take the next wide range is sequentially determined as a comparison target. In the process, the random number selection function 103 selects another sub-random number generation function 102 that generates a random number sequence that includes the specific random number and has the narrowest range in which the relationship is established. Then, the random number selection function 103 outputs another random number generated based on the same information used when generating the specific random number from the random number sequence generated by the selected other sub-random number generation function 102. The random number 106 to be selected is selected.

  On the other hand, the random number selection function 103 does not hold the relationship in the determination, and the specific random number generated by the specific sub-random number generation function 102 is generated. When it is determined that it is not included in the range of the random number sequence generated by the narrower sub-random number selection function 102, the specific random number is selected as the random number 106 to be output.

  That is, in the random number generation device 100 according to the present embodiment, the random number selection function 103 establishes a relationship in which a specific random number included in the range of the random number sequence of interest is included in the range of another random number sequence that is narrower than that range. Judge whether to do. Then, when the relationship is established, the random number selection function 103 determines whether or not the relationship is established, among the other random number sequences in the narrow range of values, the wide range next to the range of the random number sequence of interest. In the process of sequentially determining other random number sequences that can adopt the comparison target as the comparison target, when generating the specific random number from among the random number sequences that include the specific random number and have the narrowest range of values for which the relationship is established Select another random number generated based on the same information to be used. On the other hand, if the specific random number is not included in the range of the other random number sequence that is narrower than the range of the random number sequence of interest, the random number selection function 103 selects the specific random number.

  By such processing procedure, the random number selection function 103 configures a random number sequence (random number 106) to be generated.

  Here, the random number selection function 103 can control the operation of each sub-random number generation function 102 based on random number range information (value range) 105 received from the outside of the random number generation device 100. That is, the random number selection function 103 can grasp the range of the random number sequence to be generated by the plurality of sub-random number generation functions 102 by acquiring from the outside.

  Then, the random number selection function 103 selects the random number 106 to be output to the outside of the random number generation device 100 from the random number sequence output by each sub-random number generation function 102 in accordance with such control. In the process of this selection operation, each of the sub-random number generation functions 102 determines that it is necessary to generate a random number sequence in the determination process by the random number selection function 103 even if each of the sub-random number generation functions 102 has a device configuration that generates a random number sequence. Only the specified sub-random number generation function 102 may be configured to generate a random number sequence.

  Next, a specific example for realizing the operation of the random number selection function 103 will be described in detail with reference to FIG.

  FIG. 4 is a flowchart showing the operation of the random number selection function 103 according to the second embodiment of the present invention.

  First, the random number selection function 103 selects a specific sub-random number generation function 102 from the plurality of sub-random number generation functions 102 (step S1). The specific sub-random number generation function 102 selected at this time is a range of random number sequences output from all the sub-random number generation functions 102 other than the specific sub-random number generation function 102 among the plurality of sub-random number generation functions 102 This is a sub-random number generation function having a range of a random number sequence including. That is, in the present embodiment, the plurality of sub-random number generation functions 102 have different ranges of generated random number sequences, and the range related to one sub-random number generation function 102 includes the range of the other sub-random number generation function 102 Have Therefore, it is assumed that the sub-random number generation function 102 selected in this step is a device configuration that is the sub-random number generation function 102 having the widest range of the generated random number sequence.

  The random number selection function 103 performs control (instruction) so that the specific sub-random number generation function 102 selected in step S1 generates a random number (step S2).

  Next, the random number selection function 103 determines whether there is a sub-random number generation function 102 having a narrower range of the generated random number sequence than the specific sub-random number generation function 102 among the plurality of sub-random number generation functions 102. Is determined (step S3). The random number selection function 103 can make the determination in step S3 based on, for example, random number range information (value range) 105 received from the outside as described above.

  If the random number selection function 103 determines that the sub-random number generation function 102 having a narrow range of the generated random number sequence exists as a result of the determination in step S3 (YES in step S3), the process proceeds to step S4.

  The random number selection function 103 detects the sub random number generation function 102 having the widest range of the generated random number sequence from the sub random number generation functions 102 detected in step S3. Then, the random number selection function 103 determines whether or not the random number sequence generated by the detected sub-random number generation function 102 includes the random number generated in step S2 (sometimes referred to as a “random number of interest”). (Step S4).

  When the random number selection function 103 determines that the target random number is included in the range of the random number sequence generated by the sub-random number generation function 102 detected in step S4 as a result of the determination in step S4 (YES in step S4) ), The process proceeds to step S5.

  The random number selection function 103 newly generates a random number using the sub-random number generation function 102 detected in step S4, and returns the processing to step S3 as a random number to which attention is newly generated (step S5).

  On the other hand, if the random number selection function 103 determines in step S3 that there is no sub-random number generation function 102 having a narrower range than the sub-random number generation function 102 that generated the current random number (NO in step S3). Or if it is determined that the random number of interest is not included in the range of the random number sequence generated by the sub-random number generation function 102 detected in step S4 (NO in step S4), the process proceeds to step S6. .

  The random number selection function 103 selects (determines) the last generated random number (that is, the current random number of interest) as the random number 106 to be output by the random number generation device 100 (step S6).

  That is, the random number selection function 103 first generates a random number (a random number of interest) in step S2, and then repeats the processing from step S3 to step S5 described above. Thereby, the random number selection function 103 identifies the sub-random number generation function 102 in which the range of the generated random number sequence is narrower, and if it can be identified, newly pays attention to the random number generated by the identified sub-random number generation function 102 Repeat the process of selecting as a random number. When the random number selection function 103 determines that there is no narrower range sub-random number generation function 102 in the repetition process, the random number generated by the narrow range sub-random number generation function 102 is output. The random number 106 to be selected is selected.

  Here, the series of processes described above will be generalized and described. That is, in the present embodiment, the first and second random number generation functions that are the plurality of sub-random number generation functions 102 are different from each other in the range of the random number sequence to be generated, and the random numbers generated by the first random number generation function The value range of the sequence has a relationship including the value range of the random number sequence generated by the second random number generation function.

  Then, the random number selection function 103 determines whether or not the first random number generated by the first random number generation function is included in the value range of the second random number sequence generated by the second random number generation function. The first process to be determined can be executed. In addition, when it is determined that the random number selection function 103 is included in the first process, the second random number selection function 103 can execute a second process of selecting the second random number generated by the second random number generation function. . Then, each time the second random number is selected in the second process, the random number selection function 103 sets the second random number as a new first random number, the first process, the second process, Repeat. In the repetition process, the random number selection function 103 includes the first random number generated by the first random number generation function in the range of the second random number sequence generated by the second random number generation function. If it is determined that there is no random number 106, the first random number generated by the first random number generation function is selected as the random number 106 to be output.

  According to the random number generation device 100 according to the present embodiment described above, even if the range of the generated random number sequence is changed, the random number generated before the change among the random number values included in the changed random number sequence The random number value included in the range of the column maintains the order of the random numbers generated before the change, and the random value included in the random number sequence before the change can be determined strictly and quickly.

  When the sub-random number generation function 102 generates a substantially uniform random number value, the random number value generated by the random number generation device 100 becomes substantially uniform. Here, the value of the random number being substantially uniform means that the distribution state of the individual random number values constituting the random number sequence is substantially uniform in the range of the random number sequence generated by the random number generation device 100 ( The same applies to the following description). In other words, it can be understood that the density of individual random numbers distributed in the value range is substantially uniform.

  In the above-described embodiment, a case has been described in which the apparatus configuration is such that the information generated by the sub-random number generation function 102 is a number (numerical string). However, the present invention is not limited to such a device configuration, and as described above, the present invention can employ, for example, various types of columns formed by characters, identifiers, bit strings, coordinates, and the like. The information generated by the random number generation device 100 is not limited to the number.

  Note that the information generated by the sub-random number generator 102 may be a plurality of information instead of a single one. In this case, the information generated by the random number generator 100 is also a plurality.

[Example]
Next, see FIG. 5 for a specific example of the configuration and operation when the functions of the blocks shown in the random number generation devices 10 and 100 (FIGS. 1 and 2) described above are realized by an information processing device (computer). To explain.

  FIG. 5 is a diagram illustrating an example of a hardware configuration (hardware resource) of the information processing apparatus 1000 capable of realizing the random number generation device according to each embodiment of the present invention.

  The hardware configuration shown in FIG. 5 includes a CPU (Central Processing Unit) 401, a ROM (Read Only Memory) 402, a RAM (Random Access Memory) 403, a hard disk (storage device) 404, and a bus connecting these configurations. (Communication path) 405. Here, the storage device 404 is an example of a nonvolatile storage device.

  The function (processing) of each block described using the above-described flowchart (FIG. 4) etc. is read by the CPU 401 after the information processing apparatus 1000 receives supply of a program capable of realizing such a function. To achieve. Further, the program supplied to the apparatus can be stored in a readable / writable RAM 403 or a hard disk (HDD) 404. Here, the RAM 403 is an example of a storage device that can be temporarily stored. The HDD 404 is an example of a nonvolatile storage device.

  As a program supply method, a method such as a method of installing via various storage media such as a CD-ROM or a method of downloading from the outside via a communication line such as the Internet can be used. In such a case, it can be recognized that the present invention is constituted by a code of the computer program or a storage medium (HDD 404) in which the code is stored.

  However, the object placement apparatuses 10 and 100 described above may be realized by dedicated hardware in which logic circuit devices and the like are appropriately combined. Alternatively, when the above-described object placement devices 10 and 100 are realized by an information processing device (computer), the information processing device performs a series of functions (processing) executed by the object placement devices 10 and 100 physically or virtually. Alternatively, it may be executed in a state distributed to a plurality of information processing apparatuses.

  FIG. 6 is a diagram conceptually illustrating the hardware configuration of the object placement apparatus 500 in the example according to the first and second embodiments of the present invention. As illustrated in FIG. 6, the object placement apparatus 500 illustrated in FIG. 6 includes an object placement function 501 and, for example, the random number generation device 100 according to the second embodiment. As an example, five storage nodes (500a to 500e) are connected to the object placement apparatus 500. For example, it is assumed that the individual storage nodes (500a to 500e) are appropriately distributed on the communication network. In the following description, an example in which the object placement apparatus 500 is realized by the information processing apparatus 1000 will be described.

  However, the storage nodes (500a to 500e) may be virtually configured in the HDD 404, for example.

  In the object placement device 500, the object placement function 501 determines the placement destination of the object (hereinafter, also referred to as “object data”) 502 based on the information unique to the object. The random number generated by 10) is used by referring to correspondence information in which at least one placement destination is assigned as a partial space of the space representing the range of the plurality of types of random number sequences.

  The object placement apparatus 500 selects a storage node where the object of interest (object data) 502 should be placed from the storage nodes 500a to 500e based on the identifier information (ID) of the object 502. At the time of such selection, the object placement apparatus 500 places the object with a probability substantially proportional to the capacity that each storage node can store. The object placement device 500 has the property that even when a storage node is added or deleted, the object is placed with a probability that is approximately proportional to the capacity that each storage node can store, with minimal data movement. maintain.

  In this embodiment, in order to realize such a property, the object placement apparatus 500 prepares a one-dimensional continuous space (that is, it can also be regarded as a number line), and is proportional to the capacity of each storage node on the space. The allocated subspaces are allocated to the storage nodes so as not to overlap each other.

  FIG. 7 is a diagram illustrating an example in which the storage capacities of a plurality of storage nodes in the examples according to the first and second embodiments of the present invention are expressed as partial spaces (A to D) in a one-dimensional space. That is, in the one-dimensional space illustrated in FIG. 7, each of the storage nodes 500a to 500e represents the position in the one-dimensional space by one real number.

  In the present embodiment, the object placement device 500 generates a random number by using the random number generation device 100 (10) described above. In the object placement device 500, the range of random values generated by the random number generation device 100 is assigned coordinates corresponding to the random numbers (that is, the one-dimensional space in this embodiment: FIG. 7) to all the storage nodes. Set to include subspace. When the coordinates corresponding to the random number indicate the partial space assigned to the storage node, the object placement apparatus 500 assigns the object to the storage node assigned the partial space indicated by the coordinate corresponding to the random number. Deploy.

  On the other hand, if the coordinates corresponding to the random number do not point to the partial space assigned to the storage node, the object placement apparatus 500 will continue until the coordinates corresponding to the random number point to the partial space assigned to the storage node. And the determination of whether or not the coordinates corresponding to the random number point to the partial space assigned to the storage node is repeated.

In this embodiment, the storage nodes 500a to 500e have, for example, the storage capacity (maximum storage capacity) as shown in FIG. 6 and the following. That is,
Storage node 500a: 1.0 [TeraBytes],
Storage node 500b: 0.5 [TeraBytes],
Storage node 500c: 0.7 [TeraBytes],
Storage node 500d: 1.8 [TeraBytes],
Storage node 500e: 0.2 [TeraBytes].

  FIG. 8 is a diagram showing a correspondence table (partial space-storage node correspondence table 600) between partial spaces and storage nodes in the examples according to the first and second embodiments of the present invention.

  That is, as shown in FIGS. 7 and 8, the storage node 500a corresponds to a partial space from 0 to 1 (not including 1) in the one-dimensional space. The storage node 500b corresponds to a partial space of 1 to 1.5 (not including 1.5) on the one-dimensional space. The storage node 500c corresponds to a partial space from 2 to 2.7 (not including 2.7) in the one-dimensional space. The storage node 500d corresponds to subspaces 3 to 4 (not including 4) on the one-dimensional space and subspaces 5 to 5.8 (not including 5.8) on the same space. The storage node 500e corresponds to a subspace from 4 to 4.2 (excluding 4.2) on the one-dimensional space.

  In this embodiment, the random number generation device 100 (10) generates, for example, real numbers from −1.0 to 8.0, and generates two sub-random number generation functions 102 (a sub-random number generation function 102A and a sub-random number generation function 102B). ). In this case, the sub-random number generation function 102A generates a real number from 0.0 to 6.0 as a random number. Then, the sub-random number generation function 102B generates a real number from −1.0 to 8.0 as a random number. That is, the range of the random number sequence generated by the sub-random number generation function 102A indicates a space indicated by a real number from 0.0 to 6.0, as shown in FIG. 7, and the random number generated by the sub-random number generation function 102B is Indicates the space pointed to by a real number from -1.0 to 8.0.

  Here, a case where object data A having identifier information “a” is input to the object placement apparatus 500 will be described.

  The space indicated by the random number generated by the sub-random number generation function 102A includes all the partial spaces in this embodiment, as shown in the partial space-storage node correspondence table 600. Therefore, the random number generation device 100 uses only the sub-random number generation function 102A like the operation of the random number generation device 100 in the above-described embodiment.

  In this case, the sub-random number generation function 102A first calculates a hash related to the character string obtained by adding the sentence string “A” to the identifier information “a”. The hash value obtained by this calculation is set as hash A.

  Next, in the random number generation device 100 inside the object placement device 500, the sub-random number generation function 102A generates a random number.

  First, a random number is generated using the hash A as a seed by the sub-random number generation function 102A having the widest range of the random number sequence. Here, it is assumed that the generated random number is 1.7. In this case, since there is no other sub-random number generation function 102 whose range of the random number sequence is narrower than the sub-random number generation function 102A, the generated random number 1.7 is a random number that the random number generation device 100 should output. .

  Next, the object arrangement device 500 determines whether or not there is a partial space indicated by the random number. Since the random number is 1.7, it can be seen that there is no partial space pointed to by this random number in consideration of the relationship shown in FIGS. Therefore, in the random number generation device 100 inside the object placement device 500, the sub-random number generation function 102A generates a new random number.

  That is, the sub-random number generation function 102A generates the next random number. Here, it is assumed that the generated random number is 4.9. Also in this case, since there is no other sub-random number generation function 102 whose range of the random number sequence is narrower than the sub-random number generation function 102A, the random number 4.9 is a random number that the random number generation device 100 should output.

  Then, the sub-random number generation function 102A determines again whether or not the partial space indicated by the random number exists. Since the random number of interest is 4.9, considering the relationship shown in FIG. 7 and FIG. 8, there is no partial space indicated by the random number in this case as well. For this reason, the sub-random number generation function 102A generates a new random number.

  Also in this case, it is assumed that the random number 0.4 is obtained as a result of calculating the random number in the same manner as described above, and the value of the random number is selected as the random number to be output by the random number generation device 100.

  Then, the object placement apparatus 500 determines whether or not there is a partial space indicated by the random number 0.4 by referring to FIG. 8 (FIG. 7). Then, in this case, it can be seen that there is a partial space (A) indicated by the random number 0.4, and the partial space corresponds to the storage node 500a. Therefore, in this case, the object placement apparatus 500 places the object data A on the storage node 500a.

  Here, when the sub-random number generation function (102) generates the random numbers substantially uniformly, the random numbers generated by the random number generator are also substantially uniform. When the random numbers are substantially uniform and the range of the random number sequence includes all partial spaces, the possibility that each placement destination (storage nodes 500a to 500e in this embodiment) is selected as the placement destination of an object 502 is as follows: It is approximately proportional to the size (size) of the partial space corresponding to each placement destination.

(Add storage node)
Here, a storage node 500f having a storage capacity of 0.3 [TeraBytes] is newly added to the object placement device 500, whereby the storage node 500f is changed from 6 to 6.3 in space (6.3 is included). Let us consider the case of mapping to a subspace of (No).

  In this case, since there is a possibility that the storage nodes that store the individual object data are changed, the object placement apparatus 500 calculates the storage nodes that store the object nodes again. Here again, consider a case where a storage node in which object data A having identifier information “a” is to be placed is calculated.

  In this case, since the partial space F corresponding to the storage node 500f is added, the space indicated by the random number generated by the sub-random number generation function 102A cannot include all the partial spaces. Therefore, in such a case, the random number generation device 100 inside the object arrangement device 500 has a sub-random number space generation function 102B that can include not only the sub-random number generation function 102A but also the added partial space F. Decide to use.

  First, the object arrangement device 500 adds the sentence string “A” or the sentence string “B” to the identifier information “a”, and calculates a hash for the character string after the addition. In this embodiment, the hash calculated for the sentence string “A” is referred to as hash A, and the hash calculated for the sentence string “B” is referred to as hash B.

  Next, the random number generation device 100 inside the object placement device 500 generates a random number using the hash B as a seed by the sub-random number generation function 102B having the widest range of the generated random number sequence. Here, it is assumed that the calculated random number is 3.0. In this case, the random number 3.0 is included in the range of the random number sequence of the sub-random number generation function 102A. Therefore, as described above with reference to FIG. 4, the random number generation device 100 does not adopt (output) the random number 3.0, but generates a sub-random number having a narrower range than the range related to the sub-random number generation function 102B. A new random number is generated by the function 102A. In this case, the sub-random number generation function 102A generates a random number using the hash A as a seed. Here, it is assumed that the calculated random number is 1.7. In this embodiment, there is no random number generation means having a narrower range of random number sequences than the sub-random number generation function 102A. Therefore, the random number 1.7 is a random number that the random number generation device 100 should output.

  Next, the object placement apparatus 500 determines whether or not there is a partial space indicated by the random number 1.7. However, as shown in FIG. 8 (FIG. 7), there is no partial space corresponding to the random number. . Therefore, the random number generation device 100 performs random number generation again.

  Therefore, the random number generation device 100 inside the object placement device 500 generates a random number again according to the procedure of the flowchart shown in FIG. That is, the random number generation device 100 generates the next random number by the sub-random number generation function 102B having the widest range of the generated random number sequence. Here, it is assumed that the calculated random number is 6.2. In this case, the random number 6.2 is not included in the range of the random number sequence of the sub-random number generation function 102A having the next wide range of the random number sequence. Therefore, the random number 6.2 is a random number that the random number generation device 100 should output.

  Then, the object arrangement device 500 determines whether or not there is a partial space indicated by the random number 6.2. In this case, there is a partial space F indicated by the random number 6.2, and the storage node 500f is associated with the partial space F. Therefore, the object placement apparatus 500 moves the object data A to the storage node 500f.

  In the object placement apparatus 500 according to the present embodiment, when the placement destination (storage node) is added, the object data moves only to the added placement destination. In the object placement device 500, the random number generation device 100 included in the object placement device generates random numbers substantially uniformly. When the range of the random number sequence generated by the random number generation device 100 includes all partial spaces, the possibility that random numbers corresponding to the individual arrangement destinations including the added arrangement destinations are selected is the partial space corresponding to each arrangement destination. There is a property that it is approximately proportional to the size (size) of.

  In order to maintain such a property even when the range of the random number sequence is changed, as in the first and second embodiments described above and the random number generators 10 and 100 described in the present example. Among the random number values included in the changed random number sequence, the random number values included in the range of the random number sequence generated before the change maintain the order of the random numbers generated before the change, and the change A random number generator capable of generating a random number value included in the previous random number sequence is required.

(Delete storage node)
Next, consider a case where the storage node 500f is deleted from the object placement apparatus 500. In this case, since there is a possibility that the storage nodes that store the individual object data are changed, the object placement apparatus 500 calculates the storage nodes that store the object nodes again. Here again, consider a case where a storage node in which object data A having identifier information “a” is arranged is calculated.

  As can be seen from FIG. 8 (FIG. 7), the space indicated by the random number generated by the sub-random number generation function 102A includes all the partial spaces. Therefore, in the object arrangement device 500, the random number generation device 100 uses only the sub-random number generation function 102A.

  First, the random number generation device 100 adds the sentence string “A” to the identifier information “a” and calculates a hash for the added character string. A hash related to the sentence string “A” is a hash A.

  Next, in the object placement device 500, the random number generation device 100 generates a random number. Also in this case, the random number generation device 100 generates a random number using the hash A as a seed by the sub-random number generation function 102A having the widest range of the random number sequence. Here, it is assumed that the calculated random number is 1.7. In this case, there is no sub-random number generation function 102 whose range of the random number sequence is next to the sub-random number generation function 102A. Therefore, the random number 1.7 is a random number that the random number generation device 100 should output. Since there is no partial space indicated by the random number 1.7, the random number generation device 100 generates a random number again.

  In the random number generation device 100, the next random number calculated by the sub-random number generation function 102A is 4.9. Also in this case, the random number 4.9 generated by the sub-random number generation function 102A is a random number to be adopted. However, since the partial space indicated by the random number 4.9 still does not exist, the random number generation device 100 performs the random number generation. Generate again.

  In this case, the random number generation device 100 generates a random number again by the sub-random number generation function 102A. In this case, if the calculated random number is 0.4, there is a partial space A corresponding to this random number, so the object placement device 500 sends object data to the storage node 500a corresponding to the partial space A. Move A.

  In the object placement apparatus 500, when the placement destination (storage node) is deleted, only the object data placed at the deleted placement destination is moved. In the object placement device 500, the random number generation device 100 included in the object placement device generates random numbers substantially uniformly. When the range of the random number sequence of the random number generation device 100 includes all the partial spaces, the possibility of being selected as a new arrangement destination of the object data stored in the deleted specific arrangement destination among the remaining arrangement destinations. , There is a property of being approximately proportional to the width (size) of the partial space corresponding to each of the remaining placement destinations.

  In order to maintain such a property even when the range of the random number sequence is changed, as in the first and second embodiments described above and the random number generators 10 and 100 described in the present example, Among the random number values included in the changed random number sequence, the random number values included in the range of the random number sequence generated before the change maintain the order of the random numbers generated before the change, and before the change A random number generator capable of generating a random number value included in the random number sequence is required.

  As described above, according to the object placement apparatus 500 according to the present embodiment, a storage node that is an object placement destination is represented as a one-dimensional space (several lines) as a line segment having a length matching the storage capacity of the storage node. The random number generation device 100 repeats generation of random numbers until the random number value of interest is included in the numerical range of the allocated line segment. When a certain random number generated by the random number generation device 100 matches the number in the one-dimensional space to which any storage node is assigned, the storage node corresponding to the number is determined as the object placement destination.

  According to this embodiment having such a processing configuration, it is possible to change the range of the random number sequence when performing the above-described series of processing. This has the following advantages over the case where the range of the random number sequence is fixed.

  In other words, in the case of a device configuration in which the range of the random number sequence is fixed, storage nodes whose number exceeds the assumption cannot be assigned to the range, so that it is necessary to change the setting from the range of the random number sequence again. In this case, in the object placement device, since many random number values change based on the new range after the change, it is expected that a situation in which the storage node where each object is stored greatly changes will occur.

  On the other hand, according to the present embodiment, the object placement device 500 changes the number of storage nodes (simply the number) in response to changing the range of the random number sequence by the random number range information 105 set from the outside. Even when the number increases compared to the quantity assumed in advance, the range of the random number sequence on the number line (one-dimensional space) can be expanded. In the object placement apparatus 500, the random number values included in the random number sequence after the range is newly expanded and also included in the range before the change are the order (occurrence order) in the random number sequence before and after the change. Can be maintained as it is. In other words, according to the object placement device 500, even when a situation in which the range of the random number sequence needs to be expanded occurs, it is possible to flexibly deal with and to change the storage node to be stored. The number of cases can be minimized.

  Also, in the case of a device configuration in which the range of the random number sequence is fixed, the range of the random number sequence cannot be changed if the area on the number line to which the storage node is allocated as a partial space is very narrow. In this case, it may be necessary to repeat the generation of random numbers many times. In such a case, there is a problem that it takes time until the assignment destination is finally determined.

  On the other hand, according to the object placement apparatus 500 according to the present embodiment, even if the area on the number line to which the storage node is allocated as a partial space is very narrow, the random number range information 105 can be used from the outside. In response to the instruction, the range of the random number sequence can be narrowed according to the narrow region. This means that the number of occurrences of random numbers can be reduced. Therefore, according to the object arrangement device 500, the processing speed can be increased.

  As described above, according to the object arrangement apparatus 500 according to the present embodiment, the size of the value range to be adopted can be flexibly changed as described above. For this reason, in a system in which an object is placed on a storage node using the object placement device 500, it is not necessary to consider a random number sequence having a wide range with an excessively large margin at the start of operation. That is, such a system may prepare a random number that generates a minimum required range at the beginning of operation, and allocate a minimum storage node to the range as a partial space. In other words, in spite of the need for a small number of storage nodes at the beginning of operation, considering the future expansion of new storage nodes, a random number sequence with a wide range is adopted to install the small number of storage nodes. If assigned, it is expected that the time required to determine the location will be prolonged. On the other hand, according to the system using the object placement device 500, the range of the random number sequence adopted as described above can be flexibly changed, and the object affected by the change can be minimized. For this reason, according to the system using the object placement apparatus 500, it is possible to realize a small start using a range of a random number sequence that matches the system scale at the start of operation in order to secure a response until the placement destination is determined. It is. Furthermore, according to such a system, even when the system scale is expanded in the future, the range of the random number sequence corresponding to the system scale can be adopted, so that it is possible to prevent the response until the placement destination is determined. Can do.

  In the present embodiment, for convenience of explanation, a case where a partial space is arranged on a one-dimensional space has been described as an example. However, the object placement device according to the present invention can be applied to a multi-dimensional space. Here, the case where a partial space is arranged in a two-dimensional space as an example of a plurality of dimensions will be outlined.

  FIG. 9 is a diagram showing an example in which the storage capacity of the storage node in the examples according to the first and second embodiments of the present invention is expressed as a partial space in a two-dimensional space. The two-dimensional space shown in FIG. 9 is composed of two types of random numbers (A, B). In this two-dimensional space, as illustrated in FIG. 9, a plurality of partial spaces (A to K) are arranged in the range of real numbers 0 to 5 which are random numbers A and in the range of real numbers 0 to 4 which are random numbers B. Yes.

  As an implementation example using such a two-dimensional space, for example, a case where an object to be arranged is information (for example, map information not including height) represented in the two-dimensional space is assumed. In this case, the individual object can be allocated as a partial space within the space adopted by the object placement device while maintaining the same dimension as that of the individual object itself.

  That is, when an object composed of such two-dimensional information is arranged using the above-described object arrangement device 500 that employs the one-dimensional space, the individual object is assigned prior to the process of assigning the individual object to the partial space in the one-dimensional space. It is necessary to convert the two-dimensional information representing the object into one-dimensional information. Furthermore, depending on the implementation mode, it is necessary to convert the one-dimensional information representing the determination result of the placement destination into two-dimensional information. This means that extra time is required for a series of processing, and the processing load (processing cost) is large.

  On the other hand, in the case of a device configuration in which the two-dimensional information representing the individual object is assigned as it is as a partial space in the two-dimensional space, such extra processing burden does not occur. For this reason, according to such a device configuration, the configuration of the object placement device can be simply realized, and the object can be placed flexibly and at high speed. This is not an effect limited to the case where the object is represented by two-dimensional information. That is, such an effect can be enjoyed by adopting an object placement device that handles a multi-dimensional space to which the n-dimensional information can be assigned as it is when the object whose placement destination is to be determined is n-dimensional information (n ≧ 1). .

  In the above, this invention was demonstrated as an example applied to exemplary embodiment mentioned above and its Example. However, the technical scope of the present invention is not limited to the scope described in the above embodiments and examples. It will be apparent to those skilled in the art that various modifications and improvements can be made to such embodiments. In such a case, new embodiments to which such changes or improvements are added can also be included in the technical scope of the present invention. This is clear from the matters described in the claims.

  That is, the present invention can apply various modes that can be understood by those skilled in the art within the scope of the present invention.

  This application claims the priority on the basis of Japanese application Japanese Patent Application No. 2012-030976 for which it applied on February 15, 2012, and takes in those the indications of all here.

DESCRIPTION OF SYMBOLS 10,100 Random number generator 12 Random number generation function 101 Seed providing function 102 Sub random number generation function 13, 103 Random number selection function 14, 104a, 104b Seed information 15, 105 Random range information 16, 106 Random number sequence 401 CPU
402 ROM
403 RAM
404 HDD
405 Bus (communication path)
500 Object placement device 500a to 500e Storage node 501 Object placement function 502 Object 600 Subspace-storage node correspondence table 1000 Information processing device (computer)

Claims (14)

The same random number sequence can be generated based on the same information that is the source of random numbers, and multiple types of random number sequences that can be taken by the generated random number sequence can be generated. When the random number included in is in a range included in a range that can be taken by another random number sequence different from the range, the random number of the random number sequence of interest in a relationship included in the range that can be taken by the other random number sequence And the random numbers of the other random number sequences included in the range that the noted random number sequence can take are the same value, and appear in the same order in the random number sequence to be generated by the own device. Random number generator. When the specific random number included in the range that can be taken by the random number sequence of interest is in a relationship that is included in the range that can be taken by another random number sequence that is narrower than the range, whether or not the relationship is satisfied, Among the other random number sequences that can take the narrow range, the specific random number is included in the process of sequentially determining as another comparison target another random number sequence that can take the next wide range that can be taken by the target random number sequence And selecting another random number generated based on the same information used when generating the specific random number from among the random number sequences having the narrowest range in which the relationship is established, If the specific random number is not included in a range that can be taken by another random number sequence that is narrower than the range that can be taken by the random number sequence, the random number sequence to be generated is configured by selecting the specific random number The random number generator according to claim 1 . A plurality of random number generating means for generating the plurality of types of random number sequences;
Random number selection means for selecting a random number value generated from any of the plurality of random number generation means,
The random number selection means includes
The specific random number generated by the specific random number generation means among the plurality of random number generation means is in a value range that can be taken by another random number sequence that is narrower than the range that the random number sequence generated by the specific random number generation means can take. In the case where the relationship is included, whether the relationship is established or not is determined based on the other random number sequences that can take the narrow range of values, and the other range that can take the next wide range of values that can be taken by the random number sequence of interest. In the process of sequentially determining a random number sequence as a comparison target, the specific random number is included, and the random number sequence generated by another random number generation unit that generates the random number sequence having the narrowest range in which the relationship is established is selected from the random number sequence While selecting other random numbers generated based on the same information used to generate a specific random number,
Among the plurality of random number generation means, the specific random number generated by the specific random number generation means is generated by another random number selection means whose value range that the generated random number sequence can take is narrower than the specific random number selection means. The random number generator according to claim 2, wherein the specific random number is selected when the random number sequence is not included in an acceptable range. The first and second random number generation means, which are the plurality of random number generation means, have different value ranges that can be taken by the generated random number sequence, and range values that can be taken by the random number sequence that is generated by the first random number generation means, The random number sequence generated by the second random number generation means has a relationship including a range that can be taken,
The random number selection means includes
First processing for determining whether or not the first random number generated by the first random number generation means is included in a value range that can be taken by the second random number sequence generated by the second random number generation means. When,
A second process for selecting a second random number generated by the second random number generator when it is determined that the second process is included in the first process;
Each time the second random number is selected in the second process, the first process and the second process are repeated using the second random number as the new first random number,
When it is determined that the first random number generated by the first random number generation means is not included in a range that can be taken by the second random number sequence generated by the second random number generation means, the first random number generation means 4. The random number generator according to claim 3, wherein the first random number generated by the random number generator is selected as the specific random number.   5. The random number generator according to claim 2, wherein in the plurality of types of random number sequences, random numbers are distributed substantially uniformly in each random number sequence. 6. The random number generation device according to claim 1, wherein the random number generation device generates a random number sequence representing at least one of a numerical value, a character, an identifier, a coordinate, and a bit string. The random number generator according to any one of claims 1 to 6,
Arrangement of an object as a partial space of a space representing a range of values that can be taken by the plurality of types of random number sequences using random numbers generated by the random number generator based on information unique to the object An object placement device comprising: placement means for determining by referring to correspondence information to which a destination is assigned. Random number of interest using random number generation means that generates the same random number sequence based on the same information that is the source of the random number and that can generate multiple types of random number sequences that can be taken from different ranges. When the random number included in the range that can be taken by the sequence is in a relationship that is included in the range that can be taken by another random number sequence different from the range, the relationship that is included in the range that can be taken by the other random number sequence The random number of the random number sequence of interest and the random number of the other random number sequence included in the range that can be taken by the focused random number sequence have the same value and appear in the same order in the random number sequence to be generated A random number generation method characterized by If the specific random number included in the range of values that can be taken by the random number sequence of interest generated by the random number generation means is in a range that can be taken by another random number sequence that is narrower than the range of values, the relationship is established In the process of sequentially determining whether other random number sequences that can take the next wide range after the range that can be taken by the random number sequence of interest among other random number sequences that can take the narrow range, While selecting the other random number generated based on the same information used when generating the specific random number, from the random number sequence that includes the specific random number and has the narrowest range in which the relationship is established When the specific random number is not included in a range that can be taken by another random number sequence that is narrower than the range that can be taken by the random number sequence of interest, the random number sequence to be generated is selected by selecting the specific random number With the features Random number generating method according to claim 8, wherein that. As the random number generating means, using a plurality of random number generating means for generating a plurality of different types of random number sequences,
When the specific random number generated by the specific random number generation means among the plurality of random number generation means is in a range included in a range that can be taken by another random number sequence that is narrower than the range that can be taken by the generated random number sequence, Whether or not the relationship is established is sequentially determined by comparing, with other random number sequences that can take the narrow value range, other random number sequences that can take the next wide range after the range that the noted random number sequence can take. In the process, it is used to generate the specific random number from among the random number sequences generated by other random number generation means that generate the random number sequence that includes the specific random number and that has the narrowest range in which the relationship is established. While selecting other random numbers generated based on the same information,
Among the plurality of random number generation means, the specific random number generated by the specific random number generation means is generated by another random number selection means whose value range that the generated random number sequence can take is narrower than the specific random number selection means. The random number generation method according to claim 9, wherein the specific random number is selected when the random number sequence is not included in an acceptable range. Using the first and second random number generation means as the plurality of random number generation means, the range of values that can be taken by the generated random number sequence is different from each other, and the range of values that can be taken by the random number sequence that is generated by the first random number generation unit is , Generating a random number of a relationship including a range that can be taken by the random number sequence generated by the second random number generation means,
In selecting the specific random number,
A first determination for determining whether or not the first random number generated by the first random number generation means is included in a value range that can be taken by the second random number sequence generated by the second random number generation means; ,
A second determination for selecting the second random number generated by the second random number generation means when it is determined that the second determination is included in the first determination;
Each time the second random number is selected in the second determination, the first determination and the second determination are repeated using the second random number as the new first random number,
When it is determined that the first random number generated by the first random number generation means is not included in the range that can be taken by the second random number sequence generated by the second random number generation means, the first random number 11. The random number generation method according to claim 10, wherein the first random number generated by the generation means is selected as the specific random number. The same random number sequence can be generated based on the same information that is the source of random numbers, and multiple types of random number sequences that can be taken by the generated random number sequence can be generated. Is in a range that can be taken by another random number sequence different from that range, the random number sequence of interest that is in a range that can be taken by the other random number sequence A random number generation function in which a random number and the random number of the other random number sequence included in a range that can be taken by the focused random number sequence have the same value and appear in the same order in the random number sequence to be generated; A computer program that is executed by a computer. When the random number generation function causes the computer to have a specific random number included in a range that can be taken by the random number sequence of interest, in a range that can be taken by another random number sequence that is narrower than the range, Whether or not the relationship is satisfied is sequentially determined by comparing, with other random number sequences that can take the narrow range, the other random number sequences that can take the next wide range after the range that can be taken by the random number sequence of interest. Other random numbers generated based on the same information used when generating the specific random number from among the random number sequence that includes the specific random number and has the narrowest range in which the relationship is established. On the other hand, if the specific random number is not included in a range that can be taken by another random number sequence that is narrower than the range that can be taken by the random number sequence of interest, the generation is performed by selecting the specific random number. Construct a random number sequence to be The computer program of claim 12, characterized in that the. A plurality of random number generation functions for generating the plurality of types of random number sequences as the random number generation function,
A computer program for causing the computer to execute a random number selection function for selecting a random number value generated from any of the plurality of random number generation functions,
By the random number selection function,
Among the plurality of random number generation functions, a specific random number generated by a specific random number generation function is in a value range that can be taken by another random number sequence that is narrower than a range that can be taken by a random number sequence generated by the specific random number generation function If the relationship is included, whether or not the relationship is satisfied is determined based on whether or not the narrowest range of random numbers can take the next widest range of values that the focused random number sequence can take. Among the random number sequences generated by other random number generation functions that generate the random number sequence that includes the specific random number and has the narrowest range in which the relationship is satisfied, While selecting other random numbers generated based on the same information used when generating the specific random number,
Among the plurality of random number generation functions, the specific random number generated by the specific random number generation function is generated by another random number selection function whose value range that can be taken by the generated random number sequence is narrower than the specific random number selection function The computer program according to claim 13, wherein the specific random number is selected when the random number sequence is not included in an acceptable range.

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