JP4246666B2 - Node position calculation program and node position calculation apparatus - Google Patents

Description

  The present invention relates to a node position calculation program for calculating a position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination, and a node position calculation More particularly, the present invention relates to a node position calculation program, a node position calculation method, and a node position calculation apparatus capable of quickly and efficiently performing node arrangement calculation even when the number of nodes is large.

  Conventionally, in order to easily grasp the flow of each work that occurs in a project and the dependency of the work, network-types such as PDM (Precedence Diagram), ADM (Arrow Diagram), PERT (Program Evolution and Review Technique) diagrams, etc. Directed graphs are frequently used.

  FIG. 14 shows an example of such a networked directed graph. As shown in FIG. 14, in this directed graph, the dependency relationship between nodes is represented by a directional edge (branch). Here, since the edge extending from the node a to the node d is difficult to see because it intersects with the edge extending from the node b to the node f, a method of rearranging the nodes to make the directed graph easier to see has been developed.

  For example, Non-Patent Document 1 discloses a node placement algorithm that creates a directed graph that is easy to view by rearranging nodes. FIG. 15 is an explanatory diagram for explaining this conventional node arrangement algorithm.

  As shown in FIG. 15, in this node placement algorithm, the nodes a to f are assigned to several layers to be hierarchized, the positions of the nodes are switched in each layer, and the length of the edge connecting the nodes is minimized. To reduce the number of intersections between edges.

  Further, in this node placement algorithm, when nodes are connected across layers such as node b to node f or node d to node f, dummy nodes D1 to D3 are inserted for each layer, Split edges connecting nodes. The reason for inserting the dummy node is to prevent an edge connecting the nodes across the layers from intersecting with another edge.

  Then, the positions of the nodes including the dummy nodes D1 to D3 are replaced in each layer to reduce the number of intersections between the edges, and finally, the dummy nodes D1 to D3 are removed to create an easy-to-see effective graph. .

Kozo Sugiyama, Shojiro Tagawa and Mitsuhiko Toda, "Methods for visual understanding of hierarchical system structures", IEEE Trans. On Systems, Man, and Cybernetics, vol.SMC-11, no.2, pp.109-125, 1981.

  However, in the conventional technique of Non-Patent Document 1, the optimal placement position of the nodes is calculated so as to minimize the number of intersections between edges. However, the calculation time increases rapidly as the number of nodes increases, and the optimal There was a practical problem because the solution could not be obtained quickly.

  In other words, when improving the visibility of a directed graph, it is not always desirable to obtain an optimal solution that performs a long calculation and minimizes the number of intersections between edges, and efficiently obtains a solution close to the optimal solution in a short time. This is often desirable in practice.

  The present invention has been made to solve the above-described problems caused by the prior art, and a node position calculation program and a node position calculation capable of quickly and efficiently performing node arrangement calculation even when the number of nodes is large. It is an object to provide a method and a node position calculation apparatus.

  In order to solve the above-described problems and achieve the object, the present invention provides a directional edge that connects two nodes, a parent node that becomes a connection source, and a child node that becomes a connection destination. A node position calculation program used in a process for calculating an arrangement position, wherein one-dimensional position information in each hierarchy of nodes included in a directed graph in which the parent node is assigned to a hierarchy higher than a child node is genetically A storage procedure for storing a gene used in the algorithm and a sequence constituted by the gene as a chromosome used in the genetic algorithm, and a genetic location of the node for each layer based on the chromosome stored by the storage procedure And a calculation procedure calculated by an algorithm.

  In addition, the present invention provides a node assignment procedure for assigning each node included in the directed graph to each hierarchy so that the parent node belongs to a higher hierarchy than the child node based on the connection relationship between the parent node and the child node. The storage procedure further includes storing one-dimensional position information in each layer of the node assigned to each layer by the node assignment procedure as the gene, and storing a sequence constituted by the gene as the chromosome. Features.

  Further, according to the present invention, when the node assignment procedure includes a parent node and a child node connected across a plurality of hierarchies, a dummy node connected to both the parent node and the child node is added to the dummy node. One is generated for a set of a parent node and a child node, and the generated dummy node is assigned to the plurality of hierarchies.

  Further, according to the present invention, when the node assignment procedure is such that a connection relation of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a higher hierarchy than the child node, The connection relationship between the connection source and the connection destination with the child node is reversed, and the parent node and the child node whose connection relationship is reversed are assigned to each hierarchy.

  Furthermore, the present invention is a node position calculation method for calculating the arrangement position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination. The one-dimensional position information in each hierarchy of nodes included in the directed graph in which the parent node is assigned to a hierarchy higher than the child node is used as a gene used in a genetic algorithm, and an array constituted by the gene is A storage step of storing as a chromosome used in the genetic algorithm, and a calculation step of calculating a placement position of the node for each hierarchy by the genetic algorithm based on the chromosome stored in the storage step, To do.

  Further, the present invention is a node position calculation device that calculates the arrangement position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination. The one-dimensional position information in each hierarchy of nodes included in the directed graph in which the parent node is assigned to a hierarchy higher than the child node is used as a gene used in a genetic algorithm, and an array constituted by the gene is Storage means for storing as a chromosome used in the genetic algorithm, and a calculation means for calculating the arrangement position of the node for each layer based on the chromosome stored by the storage means, using the genetic algorithm, To do.

  According to the present invention, one-dimensional position information in each hierarchy of nodes included in a directed graph in which a parent node is assigned to a hierarchy higher than a child node is used as a gene used in a genetic algorithm, and is configured by a gene. The sequence is stored as a chromosome used in the genetic algorithm, and the placement position of the node for each hierarchy is calculated by the genetic algorithm based on the stored chromosome, so even if the number of nodes is large, the placement of the node is calculated There is an effect that it can be performed quickly and efficiently.

  Further, according to the present invention, each node included in the directed graph is assigned to each hierarchy so that the parent node belongs to a higher hierarchy than the child node based on the connection relationship between the parent node and the child node, Since the one-dimensional position information in each layer of the node assigned to is used as a gene and the sequence composed of the gene is stored as a chromosome, each node in the directed graph is efficiently hierarchized, and the node placement calculation It is possible to perform quickly and efficiently.

  Further, according to the present invention, when a parent node and a child node are connected across a plurality of hierarchies, a dummy node connected to both the parent node and the child node is connected to the parent node and the child node. Since one group is generated and the generated dummy nodes are assigned to multiple hierarchies, the number of dummy nodes to be added is reduced, and even when the number of nodes is large, the calculation of node placement is quick and efficient. There is an effect that it can be performed manually.

  In addition, according to the present invention, when the connection relationship of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a higher hierarchy than the child node, the connection between the parent node and the child node is possible. Since the parent node and child node whose connection relation is reversed are assigned to each hierarchy, the node placement calculation is easy and efficient by once canceling the loop state. By restoring the connection relationship between the parent node and the child node after the placement calculation is completed, the optimal placement of the node can be obtained even when the node connection relationship is in a loop state. There is an effect.

  Exemplary embodiments of a node position calculation program, a node position calculation method, and a node position calculation apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

  First, the functional configuration of the node position calculation apparatus according to the present embodiment will be described. FIG. 1 is a functional block diagram illustrating a functional configuration of the node position calculation apparatus according to the present embodiment. This node position calculation device is a device that calculates the arrangement position of a node so as to make it easier to see a directed graph by eliminating the intersection of edges connecting between nodes in an effective graph.

  This node position calculation device calculates the arrangement position of the nodes of the effective graph using a genetic algorithm. At that time, each node is assigned to a layer so that the parent node belongs to a layer higher than the child node, and the vertical position coordinates of each node are fixed.

  The horizontal position coordinates of the nodes are used as genes used in the genetic algorithm, and the chromosomes used in the genetic algorithm are constructed using the sequences of the genes, and gene operations such as crossover, mutation, and selection are performed on the chromosomes. To calculate the position of the node that eliminates the intersection of edges. In this way, by considering only the horizontal position coordinates of a node as a constituent element of a chromosome and performing a genetic operation, the node arrangement calculation can be performed quickly and efficiently.

  As illustrated in FIG. 1, the node position calculation device includes an input unit 10, a display unit 11, a main storage unit 12, an auxiliary storage unit 13, a node allocation unit 14, a node position calculation unit 15, a node arrangement unit 16, and a control unit 17. Have

  The input unit 10 is an input device such as a keyboard or a mouse. The display unit 11 is a display device such as a display. The main storage unit 12 is a main storage device such as a RAM (Random Access Memory) and temporarily stores various data such as chromosomes.

  The auxiliary storage unit 13 is an auxiliary storage device such as a hard disk device or an optical disk device, and stores an operating system, various programs, data related to an effective graph for performing node arrangement calculation, and the like. The data related to the directed graph includes position information of each node, information on a combination of a parent node and a child node connected by an edge, and the like.

  The node assigning unit 14 performs processing for assigning each node to each layer based on a connection relationship between a parent node that is a connection source of edges that connect nodes and a child node that is a connection destination. The node allocation unit 14 includes a layer setting unit 14a, a dummy node adding unit 14b, and a loop cutting unit 14c.

  The layer setting unit 14 assigns each node included in the directed graph to a plurality of layers, and performs a process of setting the layers. FIG. 2 is an explanatory diagram for explaining processing for assigning each node to a plurality of layers.

  As shown in FIG. 2, the layer setting unit 14 sets the node a so that the parent node belongs to a higher layer than the child node based on the connection relationship between the parent node that is the connection source of the edges and the child node that is the connection destination. The process of assigning ~ f to each of layers 1 to 3 is performed.

  Returning to the description of FIG. 1, when the parent node and the child node are connected across the layers, the dummy node adding unit 14b sets the dummy node connected to both the parent node and the child node as the parent node and the child node. One is generated for a set of child nodes, and the generated dummy node is assigned to the layer. FIG. 3 is an explanatory diagram illustrating a process of assigning dummy nodes to layers.

  As shown in FIG. 3, when the parent node b and the child node f, or when the parent node d and the child node f are connected across the layers, the dummy node adding unit 14b detects that, Nodes D1 and D3 are generated. In particular, when the parent node b and the child node f are connected across a plurality of layers 2 and 3, only one dummy node D1 is generated for the set of the parent node b and the child node f. A process of assigning a dummy node D1 to layers 2 and 3 is performed.

  Thus, by assigning only one dummy node D1 to layers 2 and 3, the number of nodes can be reduced, and the calculation time when applying the genetic algorithm can be reduced.

  Returning to the description of FIG. 1, the loop cutting unit 14c determines that the edge is connected when the connection relation of a plurality of nodes included in the directed graph is in a loop state and the edge connecting the nodes extends from the lower layer to the upper layer. By reversing the direction, the connection relationship between the parent node that is the connection source and the child node that is the connection destination is reversed.

  That is, the loop cutting unit 14c sets the child node as the parent node and the parent node as the child node when the layer where the parent node is arranged becomes a lower layer than the layer where the child node is arranged. Then, a process of cutting the loop is performed by assigning parent nodes and child nodes whose connection relations are reversed to the layers. FIG. 4 is an explanatory diagram for explaining the process of reversing the connection relationship between the parent node and the child node.

  In the example of FIG. 4, in the connection relationship between the node f and the node c, the layer 4 where the node f as the parent node is arranged becomes a lower layer than the layer 2 where the node c as the child node is arranged, Node c, node e, and node f form a loop. In this case, the loop cutting unit 14c reverses the connection relationship between the node f and the node c, and performs a process of setting the node c as a parent node and the node f as a child node.

  In this way, by reversing the connection relationship between the parent node and child node, complicated processing is not required, and the parent node and child node are assigned to the upper and lower layers, respectively, to eliminate the loop state. Thus, the calculation of the node arrangement position described below can be easily performed using the same algorithm as that of a normal node.

  Returning to the description of FIG. 1, the node position calculation unit 15 stores the one-dimensional horizontal position coordinate in each layer of the node as a gene, and stores the sequence constituted by the gene in the main storage unit 12 as a chromosome. Using the obtained chromosomes, a process for calculating an optimal arrangement position of nodes with few edge crossings by a genetic algorithm is performed.

  Specifically, the node position calculation unit 15 performs genetic operations such as crossover, mutation, and selection using a genetic algorithm to change the generation of chromosomes. Then, each time the generation of chromosomes is changed, the node position calculation unit 15 evaluates the arrangement position of the node specified by the chromosome using a predetermined evaluation function, and selects a chromosome having a low evaluation. When the generation change proceeds a predetermined number of times, the calculation process is terminated. This evaluation function will be described in detail later.

  FIG. 5 is a diagram illustrating an example of calculating the optimum arrangement position of nodes, and FIG. 6 is a diagram illustrating an example of chromosomes corresponding to the node arrangement shown in FIG. In the example of FIG. 5, the edge extending from the node a to the node d intersects with the edge extending from the node b to the node e. In order to eliminate the intersection of the edges, the node position calculation unit 15 obtains an optimal node arrangement position using a genetic algorithm.

  The chromosome 60 when the edges intersect is represented as “121321” as shown in FIG. 6. Here, each number of the chromosome 60 is information on the horizontal position of the nodes a to f for each layer, and represents the order of the nodes counted from the left side of FIG. 5 for each layer. Then, the chromosome 61 after the genetic algorithm is applied by the node position calculation unit 15 and the crossing between the edges is resolved becomes “121231”.

  Here, the evaluation function for evaluating the arrangement position of the node represented by the chromosome will be described. FIG. 7 is a diagram illustrating an example of the node path data 70 that stores the connection relationship between nodes, and FIG. 8 is a diagram illustrating an evaluation process for evaluating the arrangement status of nodes. The node path data 70 is stored in the main storage unit 12.

  As illustrated in FIG. 7, the node path data 70 is data that stores a connection relationship between a parent node and a child node, and stores layer and path information. A layer is information on a layer to which a parent node and a child node belong. For example, “1-2” indicates that the parent node belongs to layer 1 and the child node belongs to layer 2. The path is information indicating a combination of a parent node and a child node that are connected to each other. For example, (a, c) indicates that the parent node a and the child node c are connected.

  Also, here, the chromosome that specifies the position information of the node is evaluated under the following conditions. “Condition: In a combination of paths (x, y) and (x ′, y ′) in which a parent node and a child node are connected, Px, Py, Px ′ and Py ′ are changed to x, y, x ′ and y ′. Where Px ≦ Px ′ and Py ≦ Py ′ ”. The number of path combinations that do not satisfy this condition is used as an evaluation function when evaluating a chromosome in the genetic algorithm.

  An example in which the arrangement status of nodes is evaluated based on this condition is shown in FIG. As shown in FIG. 8, the node position calculation unit 15 compares the horizontal position coordinates of the nodes for all combinations of paths, and performs a process of checking whether or not the above condition is satisfied.

  For example, in the path combinations (a, c) and (a, d), as shown in FIG. 6, the horizontal coordinate position Pa of the node a is common and Pa = Pa, and the horizontal position of the node c and the node d Since the relationship of coordinates is Pc <Pd, the above condition is satisfied and the evaluation is “OK”.

  In the path combinations (a, c) and (b, d), the relationship between the horizontal position coordinates of the node a and the node b is Pa <Pb, and the relationship between the horizontal position coordinates of the node c and the node d is Pc. Since <Pd, the above condition is satisfied, and the evaluation is “OK”. Similarly, the evaluation is “OK” for the path combinations (a, c) and (b, e) and the path combinations (a, d) and (b, d).

  However, for the path combinations (a, d) and (b, e), the relationship between the horizontal position coordinates of node a and node b is Pa <Pb, and the relationship between the horizontal position coordinates of node d and node e is Pd. Since> Pe, the above condition is not satisfied and the evaluation is “impossible”. Also, the evaluation is “impossible” for the combinations (b, d) and (b, e) of the paths.

  In this example, the number of combinations of paths that cannot be evaluated is 2, and this value is the value of the evaluation function. Chromosomes with large evaluation function values are assumed to have low fitness, and are deceived when a genetic algorithm is applied. Only chromosomes with small evaluation function values are left. In this way, it is possible to efficiently obtain the optimal solution for the node arrangement position.

  Although FIGS. 5 to 8 have been described with respect to the case where there is no dummy node, the optimal node arrangement position can be obtained in the same manner when there is a dummy node. FIG. 9 is a diagram illustrating an example of calculating an optimal arrangement position of a node when there is a dummy node, and FIG. 10 is a diagram illustrating an example of a chromosome corresponding to the node arrangement illustrated in FIG.

  FIG. 9 shows dummy nodes D1 and D3 added by the dummy node adding unit 14b. As shown in FIG. 10, the node position calculation unit 15 adds the horizontal position coordinates of the dummy nodes D1 and D3 to generate an array “12131223” of the chromosome 100. Here, each number of the chromosome 100 is information on the horizontal positions of the nodes a to f and the dummy nodes D1 and D3 for each layer, and represents the order of the nodes counted from the left side of FIG. 9 for each layer.

  Then, the node position calculation unit 15 performs genetic operations such as crossover, mutation, and selection using a genetic algorithm, and calculates an arrangement position of a node that eliminates the intersection of edges. FIG. 10 shows the arrangement “12121232” of the chromosome 101 after the intersection of the edges is eliminated.

  Here, since the dummy node D1 extends over the two layers of layer 2 and layer 3, for example, when the horizontal positions of the dummy node D1 and the node d belonging to the layer 2 are switched, the dummy node D1 and the layer Control is performed so that the horizontal position with the dummy node D3 belonging to 3 does not overlap.

  Returning to the description of FIG. 1, the node placement unit 16 outputs a valid graph in which nodes are placed to the display unit 11 based on the information on the optimal coordinate position of the node calculated by the node position calculation unit 15. To do.

  At that time, the node placement unit 16 deletes the dummy node added by the dummy node addition unit 14b, and extends from the parent node to the child node and the end point of the edge extending from the parent node to the dummy node, as shown in FIG. The processing is performed by connecting the start points of the edges into one edge. In addition, the node placement unit 16 performs a process of restoring the connection relationship between the parent node and the child node reversed by the loop cutting unit 14c to the connection relationship before the reversal process.

  The control unit 17 is a control unit that totally controls the node position calculation device. The control unit 17 manages data exchange between the functional units.

  Next, a processing procedure of node arrangement processing performed by the node position calculation device will be described. FIG. 11 is a flowchart showing a processing procedure of node arrangement processing performed by the node position calculation apparatus.

  As shown in FIG. 11, first, the layer setting unit 14a of the node position calculation device acquires the position information of each node and the connection information between nodes stored in the auxiliary storage unit 13 (step S101). And the layer setting part 14a performs the hierarchization process which allocates each node to a layer so that a parent node may belong to a layer higher than a child node based on the acquired positional information and connection information (step S102).

  Here, when the connection relationship of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a higher layer than the child node, the layer setting unit 14a sets the parent node to a lower layer. Assign temporarily.

  Subsequently, the dummy node adding unit 14b detects whether or not the parent node and the child node are connected across the layers. When the parent node and the child node are connected across the layers, the dummy node adding unit 14b is connected to the parent node and the child node. One dummy node is generated for a set of a parent node and a child node, and a dummy node addition process for assigning the generated dummy node to the layer is performed (step S102).

  The loop cutting unit 14c detects whether or not the parent node is temporarily assigned to a lower layer than the child node by the layer setting unit 14a because the connection relation of the plurality of nodes included in the directed graph is in a loop state. If it is temporarily assigned to a lower layer, the connection relationship between the parent node and the child node is reversed, the child node is set as the parent node, the parent node is set as the child node, and the loop is disconnected. Processing is performed (step S104).

  Thereafter, the node position calculation unit 15 generates a chromosome to be used in the genetic algorithm from the coordinates of the horizontal position of each node (step S105), and performs genetic operations such as crossover, mutation, and selection using the genetic algorithm. Generation calculation processing is performed to obtain the optimal arrangement (step S106).

  After completion of the generation calculation process, the node placement unit 16 reverses the connection relationship between the parent node and the child node reversed in step S104 again, and sets the parent node as a child node and the child node as a parent node. Thus, a process for restoring the cut loop is performed (step S107).

  Further, the node placement unit 16 deletes the dummy node added in step S103, and performs a process of connecting the parent node and the child node connected to the dummy node as shown in FIG. 9 (step S108).

  Thereafter, the node placement unit 16 performs a process of outputting the effective graph from which the loop is restored and the dummy nodes are removed to the display unit 11 (step S109), and ends this node placement process.

  By the way, the node position calculation apparatus and the node position calculation method described in the above embodiments can be realized by executing a program prepared in advance on a computer system such as a personal computer or a workstation.

  Therefore, in the following, a computer system that executes a node position calculation program having the same function as the node position calculation apparatus (node position calculation method) described in the above embodiment will be described.

  FIG. 12 is a system configuration diagram illustrating a configuration of the computer system 200 according to the present embodiment, and FIG. 13 is a block diagram illustrating a configuration of the main body unit 201 according to the computer system 200 illustrated in FIG.

  As shown in FIG. 12, a computer system 200 according to the present embodiment includes a main body 201, a display 202 for displaying information such as an image on a display screen 202a according to an instruction from the main body 201, and the computer system 200. A keyboard 203 for inputting various information and a mouse 204 for designating an arbitrary position on the display screen 202a of the display 202.

  Further, as shown in FIG. 13, the main body 201 in the computer system 200 includes a CPU 221, a RAM 222, a ROM 223, a hard disk drive (HDD) 224, a CD-ROM drive 225 that accepts a CD-ROM 209, and a flexible disk. An FD drive 226 that accepts an (FD) 208; an I / O interface 227 that connects the display 202, keyboard 203, and mouse 204; and a LAN interface 228 that connects to a local area network or wide area network (LAN / WAN) 206 Prepare.

  Further, a modem 205 for connecting to a public line 207 such as the Internet is connected to the computer system 200, and another computer system (PC) 211 and server 212 are connected via a LAN interface 228 and a LAN / WAN 206. In addition, a printer 213 and the like are connected.

  The computer system 200 implements a node position calculation device (node position calculation method) by reading and executing a node position calculation program recorded on a predetermined recording medium.

  Here, the predetermined recording medium is not limited to “portable physical medium” such as flexible disk (FD) 208, CD-ROM 209, MO disk, DVD disk, magneto-optical disk, IC card, etc. Connected to internal and external hard disk drives (HDD) 224, “fixed physical media” such as RAM 222 and ROM 223, public line 207 connected via modem 205, other computer system 211 and server 112 Any recording medium that records a node position calculation program readable by the computer system 200, such as a “communication medium” that holds the program in a short period of time when the program is transmitted, such as a LAN / WAN 206 that is executed.

  In other words, the node position calculation program is recorded on a recording medium such as the above-mentioned “portable physical medium”, “fixed physical medium”, “communication medium”, etc. so as to be readable by the computer. Implements a node position calculation device and a node position calculation method by reading and executing a node position calculation program from such a recording medium.

  Note that the node position calculation program is not limited to be executed by the computer system 200, and when the other computer system 211 or the server 212 executes the node position calculation program, or in cooperation with these, The present invention can be similarly applied to a case where a position calculation program is executed.

  As described above, in this embodiment, the node position calculation unit 15 genetically calculates one-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a layer higher than the child node. The gene used in the algorithm is stored in the main memory 12 as a chromosome used in the genetic algorithm, and the arrangement position of the node for each layer is calculated by the genetic algorithm based on the stored chromosome. Therefore, even when the number of nodes is large, the node arrangement calculation can be performed quickly and efficiently.

  Further, in this embodiment, the layer setting unit 14a sets each node included in the directed graph based on the connection relationship between the parent node and the child node so that the parent node belongs to a higher layer than the child node. Since the one-dimensional position information in each layer of the node assigned to each layer is a gene and the sequence composed of the gene is stored as a chromosome in the main storage unit 12, each node in the directed graph is It is possible to efficiently stratify and perform node arrangement calculation quickly and efficiently.

  In this embodiment, when the parent node and the child node are connected across a plurality of layers, the dummy node adding unit 14b sets the dummy node connected to both the parent node and the child node as the parent. Since one node is generated for each set of nodes and child nodes, and the generated dummy nodes are assigned to multiple layers, the number of dummy nodes to be added is reduced, and even if the number of nodes is large, node placement calculation is performed. It can be done quickly and efficiently.

  Further, in this embodiment, when the connection relationship of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a higher layer than the child node, the loop cutting unit 14c Since the connection relationship between the connection source and the connection destination with the child node is reversed and the parent node and child node whose connection relationship is reversed are assigned to each layer, the arrangement of the nodes is canceled by once canceling the loop state The calculation can be executed easily and efficiently, and after the placement calculation is completed, the optimal placement of the nodes can be achieved even when the connectivity of the nodes is in a loop state by restoring the connectivity between the parent and child nodes. Can be obtained.

  Although the embodiments of the present invention have been described so far, the present invention can be implemented in various different embodiments within the scope of the technical idea described in the claims other than the embodiments described above. Is also good.

  For example, in the present embodiment, a case has been described in which the present invention is applied to a directed graph in which an upper layer in which a parent node is disposed is above and a lower layer in which a child node is disposed is below. However, the present invention is not limited to this, and the present invention can be similarly applied to a directed graph in which the top and bottom are inverted, an effective graph that is horizontally oriented, and the like.

  In addition, among the processes described in this embodiment, all or part of the processes described as being performed automatically can be performed manually, or the processes described as being performed manually can be performed. All or a part can be automatically performed by a known method.

  In addition, the processing procedure, control procedure, specific name, and information including various data and parameters shown in the above-mentioned document and drawings can be arbitrarily changed unless otherwise specified.

  Each component of each illustrated device is functionally conceptual and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution / integration of each device is not limited to that shown in the figure, and all or a part thereof may be functionally or physically distributed or arbitrarily distributed in arbitrary units according to various loads or usage conditions. Can be integrated and configured.

  Further, all or any part of each processing function performed in each device may be realized by a CPU and a program analyzed and executed by the CPU, or may be realized as hardware by wired logic.

(Supplementary note 1) A node position calculation program used in a process for calculating the arrangement position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination Because
One-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a higher layer than the child node is used as a gene used in a genetic algorithm, and a sequence constituted by the gene is genetically A storage procedure for storing the chromosome used in the algorithm;
A calculation procedure for calculating the placement position of the node for each hierarchy based on the chromosome stored by the storage procedure by a genetic algorithm;
A node position calculation program for causing a computer to execute.

(Additional remark 2) The node allocation procedure which further allocates each node contained in the directed graph to each hierarchy so that the said parent node belongs to a hierarchy higher than a child node based on the connection relation between a parent node and a child node is further included The storage procedure is characterized in that one-dimensional position information in each hierarchy of nodes assigned to each hierarchy by the node assignment procedure is used as the gene, and a sequence constituted by the gene is stored as the chromosome. The node position calculation program according to appendix 1.

(Supplementary Note 3) In the node assignment procedure, when a parent node and a child node are connected across a plurality of hierarchies, a dummy node connected to both the parent node and the child node is assigned to the parent node. The node position calculation program according to appendix 2, wherein one is generated for each set of child nodes and the generated dummy nodes are assigned to the plurality of hierarchies.

(Supplementary Note 4) The node assignment procedure is performed when the connection relationship of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a higher hierarchy than the child node. 4. The node position calculation program according to appendix 2 or 3, wherein the connection relation between the connection source and the connection destination is reversed, and the parent node and the child node whose connection relation is reversed are assigned to each hierarchy.

(Supplementary Note 5) A node position calculation method for calculating the position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination,
One-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a higher layer than the child node is used as a gene used in a genetic algorithm, and a sequence constituted by the gene is genetically A storage step of storing as chromosomes used in the algorithm;
A calculation step of calculating a placement position of the node for each hierarchy based on the chromosome stored by the storage step by a genetic algorithm;
The node position calculation method characterized by including.

(Supplementary Note 6) A node position calculation device that calculates a position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination,
One-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a higher layer than the child node is used as a gene used in a genetic algorithm, and a sequence constituted by the gene is genetically Storage means for storing as chromosomes used in the algorithm;
Calculating means for calculating a placement position of the node for each hierarchy based on the chromosome stored by the storage means by a genetic algorithm;
A node position calculation apparatus comprising:

  As described above, the node position calculation program, the node position calculation method, and the node position calculation apparatus according to the present invention require a node position calculation system that needs to perform node arrangement calculation quickly and efficiently even when the number of nodes is large. Useful for.

It is a functional block diagram which shows the functional structure of the node position calculation apparatus which concerns on a present Example. It is explanatory drawing explaining the process which allocates each node to a some layer. It is explanatory drawing explaining the process which allocates a dummy node to a layer. It is explanatory drawing explaining the process which reverses the connection relation of a parent node and a child node. It is a figure which shows the example of calculation of the optimal arrangement position of a node. It is a figure which shows the example of the chromosome corresponding to the node arrangement | positioning shown in FIG. It is a figure which shows an example of the node path data 70 which memorize | stored the connection relation between nodes. It is a figure explaining the evaluation process which evaluates the arrangement | positioning condition of a node. It is a figure which shows the example of calculation of the optimal arrangement position of a node in case there exists a dummy node. It is a figure which shows the example of the chromosome corresponding to the node arrangement | positioning shown in FIG. It is a flowchart which shows the process sequence of the node arrangement | positioning process which a node position calculation apparatus performs. It is a system configuration figure showing the composition of computer system 200 concerning this example. It is a block diagram which shows the structure of the main-body part 201 which concerns on the computer system 200 shown in FIG. It is a figure which shows an example of a network-shaped directed graph. It is explanatory drawing explaining the conventional node arrangement | positioning algorithm.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Input part 11 Display part 12 Main memory part 13 Auxiliary memory part 14 Node allocation part 14a Layer setting part 14b Dummy node addition part 14c Loop cutting part 15 Node position calculation part 16 Node arrangement part 17 Control part 60, 61, 100, 101 Chromosome 70 node path data

Claims (5)

A node position calculation program used in a process of calculating a placement position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination,
One-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a higher layer than the child node is used as a gene used in a genetic algorithm, and a sequence constituted by the gene is genetically A storage procedure for storing the chromosome used in the algorithm;
A calculation procedure for calculating the placement position of the node for each hierarchy based on the chromosome stored by the storage procedure by a genetic algorithm;
A node position calculation program for causing a computer to execute.   A node allocation procedure for allocating each node included in the directed graph to each hierarchy so that the parent node belongs to a hierarchy higher than the child node based on a connection relation between the parent node and the child node; 2. The one-dimensional position information in each hierarchy of nodes assigned to each hierarchy by the node assignment procedure is used as the gene, and a sequence constituted by the gene is stored as the chromosome. Node position calculation program described in 1.   In the node assignment procedure, when a parent node and a child node are connected across a plurality of hierarchies, a dummy node connected to both the parent node and the child node is assigned to the parent node and the child node. The node position calculation program according to claim 2, wherein one is generated for each set, and the generated dummy nodes are assigned to the plurality of hierarchies.   In the node assignment procedure, when a connection relation of a plurality of nodes included in the directed graph is in a loop state and the parent node cannot be assigned to a hierarchy higher than the child node, the node assignment procedure between the parent node and the child node is performed. The node position calculation program according to claim 2 or 3, wherein the connection relationship between the connection source and the connection destination is reversed, and the parent node and the child node whose connection relationship is reversed are assigned to each hierarchy. A node position calculation device that calculates an arrangement position of a node in a directed graph composed of a directional edge that connects two nodes, a parent node that is a connection source, and a child node that is a connection destination,
One-dimensional position information in each layer of nodes included in the directed graph in which the parent node is assigned to a higher layer than the child node is used as a gene used in a genetic algorithm, and a sequence constituted by the gene is genetically Storage means for storing as chromosomes used in the algorithm;
Calculating means for calculating a placement position of the node for each hierarchy based on the chromosome stored by the storage means by a genetic algorithm;
A node position calculation apparatus comprising:

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