JP3693262B2 - Electronic computer - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to an electronic computer having a verification function.
[0002]
[Prior art]
Some electronic calculators such as calculators have a check function. This type of electronic computer stores the key input operation and calculation result of the first calculation, and compares the key input operation and calculation result performed for the second time with the key input operation and calculation result of the first calculation. However, if there is a difference, an error is notified by a warning sound or the like.
[0003]
[Problems to be solved by the invention]
However, in the above-described conventional electronic computer, it is determined whether or not the calculation is correct by comparing the first and second key input operations and the calculation results. Or, even if the setting of the rounding switch for specifying whether to round off or round off the last digit of the designated digit is different between the first time and the second time, the input person does not know until the answer is given. Therefore, if the answer is different between the first time and the second time, you must operate the digit number specification switch and rounding switch to reset the rounding calculation state and then start the second input operation from the beginning. There was a problem that the operability was poor.
[0004]
The object of the present invention is to solve the above-mentioned drawbacks of the prior art, and when the rounding state in the second calculation is different from that in the first calculation, this is immediately notified to the input person and the subsequent useless key input An object is to provide an electronic computer with good operability that can prevent operation.
[0005]
[Means for Solving the Problems]
  In order to achieve the above object, an electronic computer of the present invention provides:
  A series of data entered in normal calculation modeIncludes numeric and arithmetic instructionsIn an electronic computer having a verification function for storing arithmetic expression data and performing verification by comparing the arithmetic expression data newly input in the verification mode with the stored arithmetic expression data,
  Input means for inputting arithmetic expression data;
  A calculation means for executing a calculation based on the calculation formula data input by the input means in the normal calculation mode;
  Rounding instruction means for instructing rounding of the operation by the calculating means;
  Rounding means for rounding the calculation result by the calculation means by rounding specified by the rounding instruction means;
  Storage means for storing the rounding instruction state of the rounding instruction means in correspondence with the arithmetic expression data input by the input means;
  After switching from the normal calculation mode to the verification mode, the newly input calculation formula data and the state of the rounding instruction means at that time are matched with the calculation formula data stored in the storage means and the rounding instruction status. Detecting means for detecting;
  When it is detected by this detection means that at least one of the arithmetic expression data and the rounding instruction state does not match.Announcement of discrepancyFirst informing means for performing,
  By the detection meansWhen it is detected that at least one of them does not match, the detected mismatch is a rounding indication state.Check that the rounding instruction states do not match.DisplaySecond informing means for performing
  (Claim 1).
[0006]
  In the electronic computer of the present invention
  The rounding instruction meansSaidSpecify either the number of digits specified, the number of digits rounded off, or the number of digits not specified for the calculation result derived by the calculation means.Equipped with meansIt is desirable (Claim 2).
[0007]
  Also,SaidRounding instruction meansIs
  SaidA digit number specifying means for specifying the number of digits after the decimal point for the calculation result derived by the calculating means;
  A truncation designation means for instructing rounding or rounding to the number of digits below the decimal point designated by the digit number designation means;,
HasIt is desirable (Claim 3).
[0008]
  Further, the storage means stores the state of the rounding instruction by the rounding instruction means for each arithmetic instruction data (+, −, ×, ÷) included in the arithmetic expression data input by the input means.Means to
  Each time the operation instruction data in the newly input arithmetic expression data is input, the detection means is the arithmetic expression data, the state of the rounding instruction means at that time, the arithmetic expression data stored in the storage means and the rounding instruction A match with the state ofEquipped with means(Claim 4).
[0011]
[Action]
  In the electronic computer according to claim 1, the input means in the normal operation mode.Includes a series of numerical values and operation instructionsWhen the arithmetic expression data is input, the arithmetic means executes an operation based on the input arithmetic expression data. When the rounding instruction means gives a rounding instruction for the calculation by the calculation means, the calculation result by the calculation means is rounded by the rounding means by the rounding designated by the rounding instruction means. At that time, the rounding instruction state of the rounding instruction means and the arithmetic expression data input by the input means are stored in the storage means in association with each other. Then, after switching from the normal calculation mode to the verification mode, the newly input calculation formula data and the state of the rounding instruction means at that time match the calculation formula data stored in the storage means and the rounding instruction status. Is detected by the detecting means, and it is detected that at least one of the arithmetic expression data and the rounding instruction state does not match.By soundBy the first notification meansThere is a report sound indicating that there is a discrepancy.Made. Also, by the detection meansWhen it is detected that at least one of them does not match, when the detected mismatch is in the rounding instruction state, the second notification means indicates that the rounding instruction state does not matchIs done.
  Therefore,A sound to the input personNotifying the mismatch of at least one of the calculation formula data and the rounding instruction statusSubsequent useless input operations can be preventedAnd the detected discrepancy is in the rounding indication state.The second notifying means gives a rounding instruction.Since the display indicating that the states do not match is performed, it is possible to notify the input person that the mismatch is in the rounding instruction state.
[0012]
In addition, according to the electronic computer described in claim 2, the calculation result derived by the calculation means is rounded in any rounding state in which the number of digits is specified, the number of digits is rounded off, or the number of digits is not specified. Can be specified by the rounding instruction means.
[0013]
According to the electronic computer described in claim 3, the number of digits after the decimal point of the calculation result derived by the calculation means is designated by the digit number designation means, and the calculation result is designated by the digit number designation means. The rounding specification means can specify whether rounding is performed in a rounding state of rounding off or rounding off to a specified number of digits so that the number of digits after the decimal point is obtained.
[0014]
Further, in the electronic computer according to claim 4, the state of the rounding instruction by the rounding instruction means is stored for each arithmetic instruction data (+, −, ×, ÷) included in the arithmetic expression data inputted by the input means. Is remembered. Each time the operation instruction data in the newly input arithmetic expression data is input, the arithmetic expression data and the state of the rounding instruction means at that time, the arithmetic expression data stored in the storage means and the state of the rounding instruction Is detected by the detecting means.
Therefore, whenever a new operation instruction data is input, a match between the rounding instruction state at that time and the rounding instruction state at the previous time when the operation instruction data was input is detected. Done.
[0017]
【Example】
An embodiment of the electronic computer according to the present invention will be described below.
[0018]
FIG. 1 is a block diagram showing the basic configuration of the electronic computer of this embodiment.
[0019]
The computer 1 shown in FIG. 1 includes a central processing unit (CPU) 2 that controls the entire computer 1 in accordance with program instructions, a read-only memory (ROM) 3 that stores a microprogram to be processed by the CPU 2, data As needed, read / write memory (RAM) 4, key input unit 5 for inputting data and switching modes to be described later, digit number input unit 6 for specifying the number of digits after the decimal point, digit An arithmetic condition input unit 7 for designating whether the last digit of the digit designated by the number input unit 6 is rounded off or truncated, and a display driving circuit for displaying numerical data and various message data output from the CPU 2 8 and a display unit 9, and an amplifier circuit 10 and a speaker 11 for amplifying and emitting a notification sound signal output from the CPU 2.
[0020]
As shown in FIG. 2, the RAM 4 temporarily stores a display register area (also serving as an input register area) 12 for storing data to be displayed on the display unit 7 and a numerical value for the CPU 2 to calculate. A calculation register area 13, a memory register area 14 for temporarily storing calculation results, and a flag register area 15 for storing the contents of table flags F and H for various conditions during program execution.
[0021]
The contents of each flag are as follows.
F = 0 Normal calculation mode
F = 1 Check mode
H = 1 Correction mode
H = 0 Cancel correction mode
[0022]
The RAM 4 has a journal memory area 16 for temporarily storing the input contents from the key input unit 5 and an area 17 for storing an address pointer Pn for designating each register of the journal memory area 16.
[0023]
The journal memory area 16 includes a numerical memory area 16a for storing input numerical values, a function memory area 16b for storing input arithmetic instructions (+,-, X, ÷, =), and calculation conditions. The rounding state memory area 16c for storing the rounding state designation data (F, C, 5/4) designated by the input unit 7 and the digit designation data (4, 2, 1,. 0, ADD2) and a digit designation memory area 16d. Each time an input for calculation is made from the key input unit 5, numerical data, calculation instruction data input immediately after that, and rounding calculation status data at that time (rounding status designation data, digit designation data) Are sequentially stored in the register of the area 16 of the journal memory designated by the address pointers P0, P1, P2, P3,.
[0024]
As shown in FIG. 3, the key input unit 5 includes a numeric key group 19, an operation command key group 20, an instruction key group 21, a memory key group 22, and a memory key group 22 arranged on the operation surface 18 of the electronic computer 1. A verification key 23 is provided.
[0025]
The numeric key group 19 includes number keys “0” to “9” for inputting numerical values from 0 to 9, respectively, and a decimal point key “.” For inputting a decimal point.
[0026]
The operation instruction key group 20 includes four operation instruction keys “+”, “−”, “×”, “÷” for inputting four operation instructions, and an equal key “=” for obtaining an answer. .
[0027]
The command key group 21 includes a plus / minus key “+/−” for switching the sign of the displayed numerical value, a percent key “%” for switching to percentage calculation, and the previous calculation result and the current calculation in the verification mode. Confirmation key “confirmation” for alternately displaying the results, clear key “C” for correcting the wrong numerical value (numerical value correction), and all the calculation data so far are erased (initialization). It consists of all clear key “AC”.
[0028]
The memory key group 22 is used to add the displayed numerical value to the numerical value stored in the memory register (input with a positive numerical value) and “M +” for subtraction (input with a negative numerical value). Memory minus key “M−”, memory recall key “MR” for recalling the value stored in the memory register, and recalling the value stored in the memory register and simultaneously erasing the memory contents Memory recall clear key “MC”.
[0029]
The verification key “verification” 23 is an instruction key for alternately switching between the standard calculation mode and the verification mode.
[0030]
The operation surface 18 of the electronic computer 1 is provided with a decimal point designation switch 26 that is an operation unit of the digit number input unit 6 and a rounding switch 25 that is an operation unit of the calculation condition input unit 7.
[0031]
The rounding switch 25 is a switch for designating how to process the fractional part. The rounding switch 25 is a free mode "F" for obtaining the fractional part as freely as possible, and the digit 1 specified by the decimal point designation switch 26. Either a cut mode “C” for truncating digits or a rounding mode “5/4” for rounding off can be designated.
[0032]
The decimal point designation switch 26 is a switch that is effective when the rounding switch 25 is set to the cut mode “C” or the rounding mode “5/4”. Any one of a 1-digit mode “1” for obtaining 1 digit, a 2-digit mode “2” for obtaining 2 digits after the decimal point, and a 4-digit mode “4” for obtaining 4 digits after the decimal point can be designated.
The decimal point designation switch 26 can also designate a fixed point mode “ADD2” for automatically inserting a decimal point in the second digit without pressing the “.” Key.
[0033]
The display unit 7 is composed of a well-known liquid crystal display. When numerical data or various message data output from the CPU 2 is input to the display drive circuit 6, the display drive circuit 6 is driven by the display drive circuit 6, and FIG. As shown in FIG. 9, numerical data such as numbers and answers, various message data, and the like are displayed on the display window 9a.
[0034]
The display window 9a is provided above the input keys on the operation surface 18 as shown in FIG. The display window 9a can display numerical values up to 8 digits. On the left side of the numerical value display area, "M" is displayed when a numerical value is stored in the memory register of the RAM 4, "K" is displayed during constant calculation, and "E" when there is an input error such as dividing a certain number by 0. Are lit up.
[0035]
The upper area of the numerical display area is a message display area such as “Checking”, “OK”, “Previous”, “This time”, “Rounding”, etc. ”Is“ OK ”when the calculation is correct as a result of the verification, and“ Previous ”is the current (verification mode) when the displayed numerical value is the previous (normal calculation mode). When “current” is different from the previous calculation in the settings of the decimal point designation switch 26 and the round switch 25, “rounding” is lit.
[0036]
In addition, in the upper left corner of the display window 9a, a symbol (+, −, ×, ÷, =) of an operation instruction input following the numerical value displayed in the display window 9a is displayed during verification. The operation symbol display section 24 is provided.
[0037]
Next, the operation of the electronic computer 1 configured as described above will be described with reference to the flowcharts of FIGS. 4 to 8 and FIG.
[0038]
When data is input from the key input unit 5 after the “AC” key is pressed, in the numeric key / function key processing routine (FIGS. 4 and 5), first, whether F = 0, that is, normal calculation It is determined whether the mode or the verification mode (step S1).
[0039]
If F = 0, it is determined whether or not the input data is input data using a numeric key (step S2). If it is a numeric key, the numerical value is stored in the display register 12. At the same time, it is displayed on the display window 9a (step S3). By repeating the input operation using this numeric key any number of times, an arbitrary digit value (up to 8 digits) is displayed on the display window 9a.
[0040]
Next, when the four arithmetic operation command keys such as “+” and “−” are operated, the input numerical data (5, 6, 3, 2.1, etc.) and the operation command data (+, − , X, ÷), rounding state designation data (F, C, 5/4) and digit designation data (4, 2, 1, 0, ADD2) at that time are address pointer Pn (initially Pn = Stored in the register memory area 16a, function memory area 16b, rounding state memory area 16c, and digit designation memory area 16d of the journal memory area 16 specified by PO) (step S4). ).
Each time this calculation operation is repeated, the address pointer Pn sequentially becomes the next address designation Pn + 1 (step S5), and calculation processing and calculation results are displayed one after another (step S6).
When the “=” key is operated, the answer is displayed on the display window 9a.
[0041]
Next, when the “verification” key 23 is operated, the verification key processing routine (FIG. 6) is executed, and “verification” is first displayed in the message display area of the display window 9a (step S17). After the address pointer Pn becomes the initial address specification P0, the flag F is F = 1, that is, the verification mode is set (steps S9 and S10).
[0042]
Further, when the “verification” key 23 is operated in the verification mode, the “verification” display is deleted (step S11), and the normal calculation mode is restored (step S12).
[0043]
In the verification mode, in the numeric key / function key processing routine (FIGS. 4 and 5), it is first determined whether or not H = 0, that is, whether or not the correction mode is set (step S13).
[0044]
When data is input from the key input unit 5 when H = 0, it is determined whether or not the input data is input data using a numeric key (step S14). The numerical value is stored in the display register 12 and simultaneously displayed on the display window 9a (step S15). By repeating this input operation using the numeric keys, an arbitrary number of digits (up to 8 digits) is displayed on the display window 9a.
[0045]
Next, when the operation instruction key is operated, the current numerical value / operation instruction / rounding operation state data that has been input and the previous numerical value / operation stored in the register of the area 16 of the journal memory specified by Pn. The instruction / rounding operation state data is compared (step S16).
[0046]
When the current numerical value / arithmetic instruction / rounding arithmetic state data and the numerical value / arithmetic instruction / rounding arithmetic state data stored in the journal memory area 16 match, the address pointer Pn is sequentially set. The next address designation Pn + 1 is obtained (step S17), and calculation processing and calculation result display processing are performed (step S18).
[0047]
Each time the operation of the numeric key and the operation instruction key is repeated, the input numerical value / operation instruction / rounding operation state data and the numerical value stored in each register of the area 16 of the journal memory designated by Pn / Operation instruction / rounding operation state data are compared one after another, and if they match, calculation processing and calculation result display processing are performed one after another (steps S16 to S18).
[0048]
When the “=” key is operated, the calculation is terminated (S19), and “OK” indicating that the calculation is correct is displayed in the message display area of the display window 9a (step S20).
[0049]
Also, the input numerical value / arithmetic instruction / rounding arithmetic state data did not match the previous numerical value / arithmetic instruction / rounding arithmetic state data stored in the register of the journal memory area 16 specified by Pn. In this case, an alarm sound is emitted from the speaker 9 (step S21), and the data that does not match is displayed blinking on the display window 9a (step S22).
[0050]
Thereafter, the flag H becomes H = 1, that is, the correction mode is set (step S23), and “current” is displayed in the message display area of the display window 9a (step S24).
[0051]
In the correction mode, when the “confirm” key is pressed, the “confirm” key processing routine (FIG. 7) is executed. The operation of the “confirm” key is valid only when the flag F is F = 1 (verification mode) and the flag H is H = 1 (correction mode). Each time the “confirm” key is pressed, The numerical values and operation command symbols inputted this time and the numerical values and operation command symbols inputted this time are displayed alternately, and the display bodies of “previous” and “current time” are displayed alternately (steps S25 to S27).
[0052]
When the same correct input as the previous time is input by the numeric key and then the same correct input as the previous time is input by the operation command key (steps S28 and S29), the flag H becomes H = 0 and the correction mode is ended. (Step S30).
[0053]
After the correction process, the address pointer Pn becomes the next address designation Pn + 1 (step S31), and then the calculation process and the calculation result display process are performed (step S32).
Thereafter, through the same processing as in steps S13 to S18, when all the numerical values / arithmetic instructions / rounding calculation state data of the previous time and the current time coincide, the “=” key is operated (step S20). “OK” is displayed in the message display area of the display window 9a (step S24).
[0054]
When the “AC” key is pressed, the “AC” key processing routine (FIG. 8) is executed, and after all of the above normal calculation and verification data are erased (step S33), the address pointer Pn is initialized. Returning to the address designation P0 (step S34), the system enters a normal calculation input waiting state.
[0055]
FIG. 9 shows a setting state example of the rounding switch 25 and the decimal point designation switch 26, a key operation example in the key input unit 5, and a display example of the display window 9a at that time. In the figure, (a) to (c) are calculation examples in the normal calculation mode, and (d) to (g) are calculation examples in the check mode performed following the operations (a) to (c).
[0056]
In (a), with the rounding switch 25 set to the free mode “F” and the decimal point designation switch 26 set to the two-digit mode “2”, the “5” key, “+” key, “6” key, “ As a result of sequentially operating the “÷” key, the calculated value “11” is displayed on the display window 9a. Also, the operation symbol display section 24 of the display window 9a has the operation instruction key operated last at this time. The operation symbol “÷” is displayed.
[0057]
In (b), after the rounding switch 25 is switched to the cut mode “C”, the “3” key and the “÷” key are sequentially operated following the operation in (a). The truncated calculation value “3.66” and the operation symbol “÷” are displayed.
[0058]
In (c), the rounding switch 25 is switched to the rounding mode “5/4” and the decimal point designating switch 26 is switched to the one-digit mode “1”, and the “2” key, “. ”Key and“ 1 ”key are operated in order, and then the“ = ”key is operated last, so that the numerical value“ 1.7 ”indicating the calculation result is displayed (the above steps S1 to S6). ).
[0059]
In (d), “verification” is displayed in the message display area of the display window 9a when the “verification” key 23 is operated (steps S7 and S8), and then the same “5” key as before. As a result of operating the “+” key, “6” key, and “÷” key in sequence, the calculated value “11” is displayed (steps S13, S14, S16 to S18).
[0060]
In (e), the rounding switch 25 is set to the same cut mode “C” as the previous time. However, as the decimal point designation switch 26 is set to the one-digit mode “1” different from the previous time, When the “3” key is operated following the operation and the “÷” key is further operated, a notification sound “pipi” is temporarily emitted from the speaker 9 and rounded to the message display area of the display window 9a. "" Is displayed blinking (steps S16, S21, S22).
In this way, when a calculation operation is performed in a different rounding calculation state from the previous time, an alarm sound is sounded, and a display indicating the content of the erroneous operation blinks to indicate that there is an error in the specification of the rounding calculation state. Can immediately notify the input person.
[0061]
In (f), since the decimal point designation switch 26 is reset to the same two-digit mode “2” as the previous time, the correct calculated value “3.66” is displayed.
[0062]
In (g), after the rounding switch 25 is switched to the same rounding mode “5/4” as in the previous time and the decimal point designation switch 26 is switched to the same one-digit mode “1” as in the previous time, the operation “f” is followed by “ Up to the “2” key and “.” Key, the same key operation was performed as before, but when the “=” key is operated due to the next operation of the numeric key “2” key different from the previous one, the speaker No. 9 “pipi” alarm sound is temporarily emitted, and the numerical value “2.2” that has been erroneously input this time flashes in the display window 9a, and the “current” indicator is displayed in the message display area. (Steps S16, S21 to S24).
[0063]
As described above, by blinking data that does not match the previous data in the display window 9a, it is possible to reliably notify the input person that there is an error in the input operation or the specification of the rounding operation state. It is possible to make the input person recognize whether such an error has occurred.
[0064]
Further, the electronic computer 1 of the present embodiment can alternately display the previous numerical value and operation instruction data and the current numerical value and operation instruction data on the display window 9a by pressing the “confirm” key. The previous input value can be confirmed on the display window 9a and the error can be immediately corrected.
[0065]
The electronic computer of the present invention is not limited to the configuration of the above embodiment.
For example, in the above embodiment, the decimal point designation switch 26 for designating how many digits after the decimal point are to be determined, and the rounding for designating whether the last one digit specified by the decimal point designation switch 26 is rounded off or rounded off. Although the case where the switch 25 is provided has been described, it goes without saying that the decimal point designation switch 26 is unnecessary in the case of a model in which the number of digits is fixed so as to obtain a certain number of digits after the decimal point.
[0066]
In the above embodiment, the previous input value and the current input value can be displayed alternately by pressing the “confirm” key, but if there is an incorrect input during the verification, the previous input value and The current input value may be automatically displayed alternately every predetermined time.
[0067]
【The invention's effect】
In short, according to the present invention, the following excellent effects can be exhibited.
[0068]
  According to the electronic computer described in claim 1, the input person is sounded.Notifying the mismatch of at least one of the calculation formula data and the rounding instruction statusSubsequent useless input operations can be preventedAnd the detected discrepancy is in the rounding indication state.The second notifying means gives a rounding instruction.Since the display indicating that the states do not match is performed, it is possible to notify the input person that the mismatch is in the rounding instruction state.
[0069]
In addition, according to the electronic computer described in claim 2, the calculation result derived by the calculation means is rounded in any rounding state in which the number of digits is specified, the number of digits is rounded off, or the number of digits is not specified. Can be specified.
[0070]
In addition, according to the electronic computer according to claim 3, the number of digits after the decimal point of the calculation result derived by the calculation means is specified, and the rounding state of either rounding off or rounding off the specified number of digits or less is specified. You can specify whether to perform rounding with.
[0071]
In addition, according to the electronic computer described in claim 4, every time operation instruction data is newly input, the state of rounding instruction at that time and the state of rounding instruction when the operation instruction data is input last time Is detected, and when it does not match, a notification is made immediately, so that it is possible to prevent a subsequent useless input operation and improve operability.
[Brief description of the drawings]
FIG. 1 is a circuit configuration diagram showing a basic configuration of an electronic computer according to an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a memory area of the electronic computer according to the embodiment.
FIG. 3 is a plan view showing an external appearance of the electronic computer according to the embodiment.
FIG. 4 is a flowchart (numerical key / function key processing routine) for explaining the operation of the electronic computer of the embodiment.
FIG. 5 is a flowchart (numerical key / function key processing routine) for explaining the operation of the electronic computer of the embodiment.
FIG. 6 is a flowchart (validation key processing routine) for explaining the operation of the electronic computer of the embodiment.
FIG. 7 is a flowchart (“confirmation” key processing routine) for explaining the operation of the electronic computer of the embodiment.
FIG. 8 is a flowchart (“AC” key processing routine) for explaining the operation of the electronic computer of the embodiment.
9 is a diagram showing a setting state example of a rounding switch and a decimal point designation switch of the electronic computer according to the embodiment, an example of key operation in a key input unit, and a display example of the display window at that time. FIG. is there.
[Explanation of symbols]
1 Electronic computer
2 Central processing unit (CPU, calculation means, rounding processing means, detection means, notification means)
3 Read-only memory (ROM, storage means)
4 Anytime write / read memory (RAM)
5 Key input part (input means)
6 digit number input part
7 Calculation condition input section
8 Display drive circuit
9 Display section (display means, notification means)
9a Display window (display means)
10 Amplifier circuit
11 Speaker (notification means)
12 Display register area (Register input register area)
13 Operation register area
16 Journal memory area (storage means)
18 Operation surface
19 numeric keys
20 Operation instruction key group
21 Command keys
23 Check key
24 Operation symbol display
25 Rounding switch (rounding instruction means, cutoff designation means)
26 Decimal point designation switch (rounding instruction means, number of digits designation means)

Claims (4)

Stores arithmetic expression data including a series of numerical values and arithmetic instructions input in the normal arithmetic mode, and performs verification by comparing the arithmetic expression data newly input in the verification mode with the stored arithmetic expression data. In an electronic computer with a check function,
Input means for inputting arithmetic expression data;
A calculation means for executing a calculation based on the calculation formula data input by the input means in the normal calculation mode;
Rounding instruction means for instructing rounding of operation by the calculating means;
Rounding means for rounding the calculation result by the calculation means by rounding specified by the rounding instruction means;
Storage means for storing the rounding instruction state of the rounding instruction means in correspondence with the arithmetic expression data input by the input means;
After switching from the normal calculation mode to the verification mode, the newly input calculation formula data and the state of the rounding instruction means at that time are matched with the calculation formula data stored in the storage means and the rounding instruction status. Detecting means for detecting;
First notifying means for performing a sound indicating that there is a mismatch when it is detected by this detecting means that at least one of the arithmetic expression data and the rounding instruction state does not match;
When the detection means detects that at least one of them does not match, a second notification that displays that the rounding instruction state does not match when the detected mismatch is the rounding instruction state Means,
An electronic computer characterized by comprising:   2. The rounding instruction means comprises means for designating one of digit designation, rounding by digit designation, and no digit designation for the calculation result derived by the calculation means. Electronic computer. The rounding instruction means includes
A digit number designating unit for designating the number of digits after the decimal point for the calculation result derived by the calculating unit;
A truncation specifying means for instructing rounding or rounding to the number of digits less than or equal to the number of digits specified by the number of digits specifying means;
The electronic computer according to claim 1, further comprising: The storage means includes means for storing the state of the rounding instruction by the rounding instruction means for each arithmetic instruction data (+, −, ×, ÷) included in the arithmetic expression data input by the input means,
The detecting means each time arithmetic instruction data in newly inputted arithmetic expression data is inputted, the arithmetic expression data, the state of the rounding instruction means at that time, the arithmetic expression data stored in the storage means and the rounding instruction 4. The electronic computer according to claim 1, further comprising means for detecting a coincidence with the state.

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