Electronic device, method for controlling display of variable, and recording medium recording variable display controlling program

An electronic device includes: a memory; and a processor. The processor causes a display section to display variables and variable values stored in the memory in a list form, causes the display section to display a first variable specified by a user operation as a first part of an expression, causes the display section to display the variables and the variable values after the first variable is displayed, causes the display section to display a second variable specified by a user operation as a second part of the expression, together with the first part, and calculates the expression based on the first part and the second part by referring to a variable value of the first variable and a variable value of the second variable to obtain a calculation result.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2014-056121 filed on Mar. 19, 2014, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an electronic device, a method for controlling displays of variables, and a recording medium recording a variable display controlling program, which are capable of displaying at least a numerical value of a variable.

Description of the Related Art

Heretofore, as a mathematical expression input device such as a scientific calculator which can receive inputs of mathematical expressions to execute calculations, for example, there has been known a mathematical expression input device configured to display a list of meanings of variables so that a user can confirm the meanings of the variables when he/she inputs a relational expression of the variables as a mathematical model (see Japanese Patent Application Laid-Open Publication No. 2000-331036).

Such mathematical expression input device displays a list of words/phrases, as the meanings of the variables, such as a driving force, mass, elastic modulus, rupee rate (i.e. a rate of Indian rupee), and yuan rate (i.e. a rate of Chinese yuan), on a screen.

The above mathematical expression input device allows a user to see the displayed list to confirm the meanings of the variables. However, a user can know only the meanings of the variables, and cannot confirm the specific numerical values of the variables, from the displayed list. To confirm the numerical values set to the respective variables, a user needs to repeatedly perform a process to select each of the variables and to retrieve a numerical value corresponding thereto. Thus, the mathematical expression input device is not always convenient for a user.

The present invention is made in view of the above problems, and an object of the present invention is to provide an electronic device, a method for controlling displays of variables, and a recording medium recording a variable display controlling program, which enable a user to collectively confirm variable values set to all variables, respectively.

SUMMARY OF THE INVENTION

According to the first aspect of the present invention, there is provided an electronic device including: a memory; and a processor, wherein the processor causes a display section to display a plurality of variables and variable values of the variables stored in the memory in a list form, causes the display section to display a first variable specified by a user operation, among the variables displayed in the list form, as a first part of an expression, causes the display section to display the plurality of variables and the variable values of the variables after the display section displays the first variable as the first part of the expression, causes the display section to display a second variable specified by a user operation, among the variables displayed in the list form, as a second part of the expression, together with the first part, and calculates the expression based on the first part and the second part by referring to a variable value of the first variable and a variable value of the second variable among the variable values to obtain a calculation result.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter embodiments where a mathematical expression input device of the present invention is applied to a scientific calculator will be described in detail with reference to the drawings. In this regard, however, the scope of the present invention is not limited to the illustrated examples.

FIG. 1is a plan view of a scientific calculator1as a mathematical expression input device of the present invention. As illustrated inFIG. 1, the scientific calculator1is equipped with an input key group2including various kinds of keys, and a display10.

The input key group2is composed of plural keys for receiving operations to input mathematical expression components such as numerical values and signs indicating calculations and/or operations to instruct to perform various processes, from a user. To each of the plural keys, a unique function is allocated. In this embodiment, the input key group2includes a numeric keypad20, cursor key21, MODE SETUP key22, SHIFT key23, sign input keys24, ALPHA key25, VARIABLE keys26, STO key27, etc.

The numeric keypad20is composed of keys each of which receives an operation to input a numerical value. The cursor key21is pressed when a user moves a cursor indicating an edit target position and/or selection target position in a predetermined direction within the display10. The cursor key21of this embodiment is configured to be capable of receiving inputs for moving the cursor in four directions of up and down, left and right.

The MODE SETUP key22is pressed when a user sets/changes a mode among various kinds of modes, which is described later. The SHIFT key23is pressed when a user changes a function of a certain key from a function described on the surface of the key to a function described above the same key, and vice versa. The sign input keys24receive inputs of signs such as of addition, subtraction, multiplication and division, and inputs of signs/functions such as of logarithm (log) and square root, necessary for inputting mathematical expressions.

The ALPHA key25is pressed when a user inputs each of variables designated by alphabet letters, A to F, M, X and Y, respectively. In this embodiment, a certain alphabet letter as a variable is input, in the mathematical expression which is being currently input, by pressing the ALPHA key25and then pressing a key corresponding to the certain alphabet letter among the VARIABLE keys26. Alternatively, in the case that an “RCL” (Recall) function is being executed and a list of stored variable values of respective variables is being displayed, each variable can be input, without pressing the ALPHA key25, by pressing a key corresponding to a certain alphabet letter among the VARIABLE keys26. Also in this case, each variable can be input by pressing the ALPHA key25and then pressing a key corresponding to a certain alphabet letter among the VARIABLE keys26.

In this embodiment, when the MODE SETUP key22is pressed and then a predetermined key of the numeric keypad20is pressed, a calculation mode can be changed to a matrix mode (see a key of “MATRIX” inFIG. 1), vector mode (see a key of “VECTOR” inFIG. 1), complex number mode (see a key of “CMPLX” inFIG. 1), etc.

The SHIFT key23is configured so that when the SHIFT key23is pressed and then a certain key of the input key group2is pressed, the content described above the certain key is input. For example, when the SHIFT key23is pressed and then a “sin” key is pressed, “sin−1” described above the “sin” key is input.

The STO key27is pressed when a user sets a variable value with respect to a certain variable. For example, when a user presses respective keys of “1”, “0”, “STO” and “A” in this order, the display10displays “10→A”, and “10” is set to variable “A”. In this embodiment, when the STO key27is pressed and then a “(−)” key is pressed, the “(−)” key being one of the VARIABLE keys26, variable “A” is automatically input. Alternatively, the scientific calculator2can be configured, so that variable “A” is input, when the ALPHA key25is pressed after the STO key27is pressed, and then the “(−)” key is pressed.

The “RCL” (Recall) function, the characters of “RCL” being written above the STO key27, is executed when the SHIFT key23is pressed and then the STO key27is pressed, to retrieve the stored variable values of the respective variables (Recall function: seeFIG. 1). When the Recall function is performed, the variable values of the respective variables (A to F, M, X and Y) stored in a later-described storage section16are displayed in a list form on the display10. This point will be described later.

A “=” key as an execution key28is pressed when a user instructs to perform calculation processing after inputting the mathematical expression.

The display10is composed of a Liquid Crystal Display (LCD), Electronic Luminescent Display (ELD) or the like, and displays various data such as characters, symbols, signs, functions and calculation results, with a plurality of dots, depending on operations in the input key group2, etc. Alternatively, for example, a touch panel may be provided integrally with the display10so as to be disposed over the entire screen surface of the display10.

Next, the internal configuration of the scientific calculator1will be described.FIG. 2is a block diagram illustrating the internal configuration of the scientific calculator1. As illustrated inFIG. 2, the scientific calculator1includes a recording medium reading section12, a display section13, a key input section14, a communication section15, the storage section16, and a Central Processing Unit (CPU)11.

The recording medium reading section12reads information from an external information recording medium12A such as a USB memory, which is detachably attached to the scientific calculator1.

The display section13is equipped with the above-mentioned display10, and causes the display10to display various pieces of information according to display signals sent from the CPU11.

The key input section14is equipped with the above-mentioned input key group2(the input key group2and the touch panel in the case of providing the touch panel as described above), and outputs key input signals corresponding to the respective keys pressed by a user to the CPU11. The CPU11receives the key input signals corresponding to the respective keys pressed by a user, causes the display section13to display the mathematical expressions corresponding to the key input signals, and performs calculations.

The communication section15is capable of being connected to a not-illustrated network so as to be able to communicate with external devices (e.g. a server, computer, etc.) connected to the network.

The storage section16is a memory which stores programs and data for executing various functions of the scientific calculator1, and functions as a work area for the CPU11. In this embodiment, the storage section16has a storage area for a memory calculation processing program160as the program of the present invention. The memory calculation processing program160causes the CPU11to execute a later-described memory calculation processing (seeFIG. 3).

The storage section16also includes a storage area for country information161, a storage area for digit separator type information162, etc. These areas will be described later. Furthermore, the storage section16includes a storage area (i.e. a variable memory163) for storing the variables of A to F, M, X and Y, and a storage area (i.e. an input type memory164) for storing input mathematical expressions. Thus, the storage section16of this embodiment functions as a variable value storing member which stores the variable values of the plural variables.

The CPU11centrally controls the respective sections/members of the scientific calculator1. Specifically, the CPU11reads out the program specified among system programs and/or various application programs stored in the respective storage areas of the storage section16, expands the read programs in the work area of the storage section16, and performs various processes in cooperation with the program expanded in the storage section16. The CPU11also controls the display section13to perform necessary displays on the display10.

Next, the operations of the scientific calculator1as the mathematical expression input device of this embodiment will be described based on the flowchart ofFIG. 3, while referring to other drawings. Also the functions of the scientific calculator1as the mathematical expression input device of this embodiment will be described.

Because the operations of the mathematical expression input device (the scientific calculator1) described below are performed according to the memory calculation processing program160illustrated inFIG. 2, also the memory calculation processing program160as the program of the present invention will be described below.

Moreover, though the explanation is omitted in the flowchart ofFIG. 3, a user can arbitrarily move the position of the cursor on the display10by operating the above-described cursor key21(for example, seeFIG. 4Gdescribed later), also in this embodiment, similarly to the conventional scientific calculator. The mathematical expressions input by user operations are stored in the storage area (i.e. the input type memory164; seeFIG. 2) of the storage section16storing the input mathematical expressions, as the occasion demands.

First, general operations/processes executed also in the conventional scientific calculator will be described here, while the variable Recall batch display processing characteristic of the present invention, namely, the processes (Steps S1to S7) following the Recall operation, will be described later. Incidentally, when a user executes another operation except the operations described later (Step S23: YES), the CPU11of the scientific calculator1shifts to another process corresponding to the executed operation, and terminates the routine illustrated inFIG. 3.

Hereinafter, the operations will be described along the specific examples in the complex number mode, illustrated inFIGS. 4A to 4J. In this case, as described above, a user changes the mathematical expression input mode to the complex number input mode by pressing the MODE SETUP key22(seeFIG. 1) and then pressing the “2” key (the key of “CMPLX” inFIG. 1) of the numeric keypad20, in this embodiment.

The CPU11of the scientific calculator1judges whether or not the mathematical expression is currently being input (Step S14), when various data such as characters (variables), signs, symbols, functions, etc. are input (Step S13: YES) by pressing any key of the numeric keypad20or the sign input keys24, or by pressing the sign input keys24while the SHIFT key23is pressed, or by pressing the ALPHA key25and then pressing any one of VARIABLE keys26(i.e. inputting any one of variables A to F, M, X and Y).

When the mathematical expression is currently being input (Step S14: YES), the process is performed to display the input data (characters, signs, symbols, functions, etc.) additionally to the currently-input mathematical expression (Step S15). When the mathematical expression is not currently being input (Step S14: NO), the process is performed to display the input data as new input data on the display10(Step S16).

At that time, as illustrated inFIG. 4Gfor example, when a user moves the position of the cursor on the display10, the CPU11of the scientific calculator1additionally displays the input data at the position of the cursor in the currently-input mathematical expression displayed on the display10(Step S15). Thus, the input mathematical expression can be arbitrary corrected.

When the execution key28, namely the “=” key, is pressed and execution operation is performed (Step S17: YES), the CPU11of the scientific calculator1performs the process to execute calculation of the input mathematical expression. At that time, if the calculation formula includes a plurality of variables, the CPU11refers to the variable values of the respective variables stored in the variable value storing member to obtain the calculation result (Step S18). Then, the CPU11performs the process to display the calculation result on the display10.

Thus, the CPU11functions as a calculation result displaying member which calculates the mathematical expression including the variable(s), input by user operations, and displays the calculation result. In this embodiment, when the execution key28(the “=” key) is pressed to perform the execution operation, the CPU11causes the display section13to display the calculation results in lower right regions on display10, for example, as illustrated inFIG. 4EandFIG. 4H.

When a store operation is performed (Step S8: YES), the CPU11of the scientific calculator1judges whether or not any one of VARIABLE keys26is pressed (Step S9). When none of VARIABLE keys26is pressed (Step S9: NO) and any one of other keys is pressed, the process corresponding to the pressed key is performed.

When the store operation is performed and any one of VARIABLE keys26is pressed (Step S9: YES), if the mathematical expression is not currently being input (Step S10: NO), the CPU11sets the numerical value of the calculation result as the variable value of specified variable X, and displays “Ans→X” and the numerical value of the result on the display10(Step S12).

Specifically, as illustrated inFIG. 4Afor example, when the STO key27is pressed after the “2” key of the numeric keypad20is pressed, and then the key of “A” among the VARIABLE keys26is pressed, the CPU11sets the input numerical value “2” as the variable value of the specified variable “A”, in the variable value storing member. Incidentally, as illustrated inFIG. 4A, the set variable value is displayed in the lower right region of the display10, in this embodiment. Similarly, when the STO key27is pressed after the “2” key of the numeric keypad20is pressed, and then the key corresponding to “B” among the VARIABLE keys26is pressed, the CPU11sets the input numerical value “2” as the variable value of the specified variable “B”, in the variable value storing member.

Similarly, as illustrated inFIG. 4B, when the STO key27is pressed after the “3” key of the numeric keypad20is pressed, and then the key corresponding to “C” among the VARIABLE keys26is pressed, the CPU11sets the input numerical value “3” as the variable value of the specified variable “C”, in the variable value storing member. By performing setting as described above, for example, variable values 2, 2 and 3 are set to variables A, B and C, respectively, as illustrated inFIG. 4C. Incidentally, the batch display illustrated inFIG. 4C, etc. will be described later.

When the Store operation is performed and any one of the VARIABLE keys26is pressed (Step S9: YES), if the mathematical expression is not currently being input and has been already input (Step S10: NO), the process is performed to set the numerical value of the calculation result as the variable value of the specified variable (Step S12).

Specifically, for example, when a certain mathematical expression is input as illustrated inFIG. 4Dand the execution key28(the “=” key) is pressed to perform the execution operation (Step S17: YES), the CPU11retrieves the variable values of the respective variables in the mathematical expression from the variable value storing member, executes calculation of the mathematical expression (Step S18), and displays the calculation result on the display10(Step S19).

When the STO key27is pressed (Step S8: YES) and then the key of “X” among the VARIABLE keys26is pressed (Step S9: YES), because the execution operation has been already performed and the mathematical expression is not being currently input (Step S10: NO), the CPU11sets the numerical value of the calculation result as the variable value of specified variable X, and causes the display section13to display “Ans→X” in an upper left region of the display10, and to display the set variable value in the lower right region of the display10, as illustrated inFIG. 4F(Step S12).

As illustrated inFIGS. 4G to 4I, also in the case that the mathematical expression is corrected (seeFIG. 4G) and the execution operation is performed (seeFIG. 4H), when the STO key27is subsequently pressed and then the key of “Y” among the VARIABLE keys26is pressed, the CPU11sets the numerical value of the calculation result of the corrected mathematical expression as the variable value of the specified variable Y (Step S12). The CPU11also causes the display section13to display “Ans→Y” in the upper left region of the display10, and to display the set variable value in the lower right region of the display10, as illustrated inFIG. 4I.

According to such setting process, as illustrated inFIG. 4J, the calculation results of the mathematical expression ofFIG. 4Dand the corrected mathematical expression ofFIG. 4Gare set as the variable values to variables X and Y, respectively. In this case, variable values 2, 2 and 3 are previously set to variables A, B and C, respectively. Sing “┘” used inFIG. 4Jand later-describedFIG. 5Eindicates division, and has the same meaning as sign “/”.

Thus, the CPU11of this embodiment functions as a variable value setting member which specifies any one of the plurality of variables depending on the user operation, and sets the variable value of the specified variable in the storage area (the variable memory163; seeFIG. 2) of the storage section16as the variable value storing member, which stores the variables.

Meanwhile, when the Store operation is executed (Step S8: YES) and then any one of the variable keys26is pressed (Step S9: YES), if the mathematical expression is being currently input (Step S10: YES), the CPU11executes calculation of the input mathematical expression, causes the display section13to display “Mathematical expression on Input→Variable” and the calculation result on the display10, and causes the storage section16to store the variable value of the variable (Step S11).

Specifically, though illustration is omitted, for example, when the STO key27is pressed to perform the Store operation (Step S8: YES) and then the key of “X” among the variable keys26is pressed (Step S9: YES) without the execution operation at the time of inputting mathematical expression “A+B+C” in the state that variable values 2, 2 and 3 of variables A, B and C are set as illustrated inFIGS. 4A and 4B, because the mathematical expression is currently being input in this case (Step S10: YES), the CPU11retrieves variable values 2, 2 and 3 of variables A, B and C from the variable value storing member (i.e. the variable memory163) to execute calculation of the mathematical expression, causes the display section13to display “A+B+C→X” and to display the calculation result “7” in the lower right region or other regions of the display10, and then causes the storage section16to store the result numerical value “7” as the variable value of variable X (Step S11).

Next, the variable recall batch display processing characteristic of the present invention will be described.

When the SHIFT key23is pressed and then the STO key27is pressed to perform the Recall operation (Step S1: YES) as illustrated inFIG. 4Cwhile the mathematical expression is being input and/or the variable value of the variable is being set by a user operation, the CPU11of the scientific calculator1performs the variable recall batch display processing.

Concretely, when the Recall operation is performed, the CPU11retrieves the previously-set variable values of variables A to F, M, X and Y from the variable memory163(seeFIG. 2) of the storage section16as the variable value storing member, and causes the display section13to display the variables (A to F, M, X and Y) and the variable values of the variables in a list form on the display10, as illustrated inFIG. 4C.

Thus, the CPU11of this embodiment functions as a variable value list displaying member which displays the list of the variable values of the variables stored in the variable value storing member (i.e. the variable memory163of the storage section16), depending on the user operation, while the mathematical expression is being input. Incidentally,FIG. 4Cillustrates the example of displaying the list of the variable values of the variables after the operations illustrated inFIGS. 4A and 4Bare performed. Because variable values 2, 2 and 3 have been already set to variables A to C but no variable value is set to variables D to F, M, X and Y, values “O” are tentatively set to these variables.

Thus, according to the configuration where the variable values of the variables can be displayed in a list form while the mathematical expression is being input and/or the variable value of the variable is being set, a user can confirm the numerical values input with respect to the respective variables at one time by seeing the displayed list of the variable values of the variables, without repeatedly confirming each of the variable values of the variables or scrolling/switching the screens during inputting of the mathematical expression and/or setting of the variable value of the variable.

As described above, according to the mathematical expression input device (the scientific calculator1) of this embodiment, a user can easily and accurately confirm the variable values set to all the variables, respectively, at one time.

On the other hand, when a user perform another operation without pressing any one of the VARIABLE keys26(Step S3: NO) while the list of the variable values of the variables is being displayed on the display10, the CPU11of this embodiment returns the current display state of the display10to the original display state preceding the above-described Recall operation (Step S4), because it is conceivable that the user could confirm the intended variable value of the variable by seeing the displayed list of the variable values of the respective variable.

Meanwhile, when a user subsequently presses any one of the VARIABLE keys26to specify a certain variable while the list of the variable values of the variables is displayed on the display10(Step S3: YES), if the mathematical expression is being currently input at the timing immediately before displaying the list of the variable values of the variables on the display10(Step S5: YES), it is conceivable that the user, who has confirmed the intended variable value of the variable, specifies the certain variable to continue to input the mathematical expression.

For this reason, in this case (Step S5: YES), the CPU11of this embodiment performs processing to additionally input the variable, which is specified by the pressing operation of any one of the VARIABLE keys26, in the mathematical expression which is being currently input (Step S6), so as to continue the inputting process of the mathematical expression. Thus, the CPU11of this embodiment functions as a listed variable inputting member which additionally input the variable in the currently-input mathematical expression when the variable value list displaying member (the CPU11itself) specifies any one of the displayed variables.

Moreover, when a user subsequently presses any one of the VARIABLE keys26to specify a certain variable while the list of the variable values of the variables is displayed on the display10(Step S3: YES), if the mathematical expression has been already input, namely, the execution operation of the mathematical expression has been performed, at the timing immediately before the list of the variable values of the variables is displayed on the display10(Step S5: NO), it is conceivable that a user sees the displayed list of the variable values of the variables in order to confirm which of the variables should be set because he/she wants to set the calculation result as the variable value of the certain variable.

For this reason, in this case (Step S5: NO), the CPU11of this embodiment performs the processing to set the numerical value of the calculation result as the variable value of the specified variable in the storage area (variable memory163; seeFIG. 2), which stores the variables, of the storage section16as the variable value storing member, and to display the variable value (Step S7).

According to such configuration, the inputting operation of the mathematical expression can be continued, and/or the calculation result can be set as the intended variable value of the variable, along with an intention of a user. Thus, the scientific calculator1as the mathematical expression input device of this embodiment is convenient for a user.

As described above, according to the scientific calculator1(the mathematical expression input device) and/or the programs of this embodiment, the CPU11is configured; to specify any one of plural variables A to F, M, X and Y according to the user operation, and to set the variable value of the specified variable in the storage section16(the variable value storing member) (i.e. a function as the variable value setting member); to calculate the mathematical expression including the variable(s) input by the user operation, and to display the calculation result on the display10(i.e. a function as the calculation result displaying member); to display the list of the variable values of the variables stored in the variable value storing member according to the user operation while the mathematical expression is being displayed (i.e. a function as the variable value list displaying member); and to additionally input the variable value in the currently-input mathematical expression when any one of the displayed variables is specified (i.e. a function as the listed variable inputting member).

Thus, a user can confirm what numerical value has been input with respect to each of the variables at one time, by seeing the displayed list of the variable values of the variables, while inputting the mathematical expression and/or setting the variable value of the variable, without repeatedly confirming the variable values of the variables one by one or scrolling/switching the screens, and can easily and accurately confirm the variable values set to all the variables, respectively, at one time.

Next, a digit separator existence setting process will be described.

For this reason, the scientific calculator1of this embodiment is configured so that a user can set whether the numerical value such as the calculation result or variable value is displayed with a digit separator(s), or without the digit separator, in such a case (Step S20).

Specifically, in this embodiment, the storage section16(seeFIG. 2) of the scientific calculator1previously stores the country information161and the digit separator type information162, as described above. Regarding separation of digits of the numerical value, a digit separator type (the way of separating the digits) is different depending on the country. For this reason, as illustrated inFIG. 5Afor example, as the digit separator type information162, the way of separating the digits with Comma (in this case, a decimal point is represented by Dot); the way of separating the digits with Dot (in this case, a decimal point is represented by Comma, contrary to the above); and the way of separating the digits with Space (this case includes the case of separating also digits after the decimal point with Space (see “Space (DN)”), and the case of not separating the digits after the decimal point (see “Space”)) are previously set.

In India, the digits of the numerical value is separated by inserting commas between hundreds place and thousands place, between ten-thousands place and hundred-thousands place, and between millions place and ten-millions place, for example, like “3,25,84,729”. In this embodiment, also Indian digit separator type is previously stored as the digit separator type information162, as illustrated inFIG. 5A. Moreover, in order to enable to select displaying the numerical value without the digit separator, the option of “Without Separator” is previously set as the digit separator type information162.

Because the digit separator type in the case of separating the digits of the numerical value is different depending on the country as described above, as illustrated inFIG. 5B, the storage section16of this embodiment previously stores, as the country information161, information correlating each country name to the digit separator information of the country in the case of the display with the digit separator, in a table form, etc.

For example, when displaying the list of the variable values of the variables on the display10as described above (Step S2), if setting is performed so that the variable values of the variables are displayed without the digit separator (seeFIGS. 6C and 6Dto be described later), the CPU11of the scientific calculator1causes the display section13to display the variable values of variables A to F, M, X and Y without the digit separator on the display10, as illustrated inFIG. 5C. If the setting is performed so that the variable values of the variables are displayed with the digit separators, and for example, if Indian digit separator type is set at that time, the variable values of variables A to F, M, X and Y are displayed with the digit separators on the display10as illustrated inFIG. 5D.

In this case, if any one of the variable values of the variables in the displayed list includes the numerical value(s) of complex number, fraction or square root, the mathematical expression becomes hard to be read if the numerical value of the variable value is displayed with the digit separators. For this reason, as illustrated inFIG. 5Efor example, the CPU11of this embodiment displays at least the numerical value(s) of complex number, fraction or square root without the digit separator in the displayed list, in the case that any one of the variable values of the variables in the displayed list includes the numerical value(s) of complex number, fraction or square root, even when a user has performed setting to display the list of the variable values of the variables with the digit separators. For example, in the case ofFIG. 5E, the variable value of “A” includes the complex number of “12345i”, and “A=123456+12345i” is displayed without the digit separator, regardless the setting of “with a digit separator”.

Hereinafter a specific example will be described with reference toFIGS. 6A to 6L. Incidentally, though the case where the Indian digit separator type is previously set will be described below, the same explanation can be applied also to the cases of performing digit separation with digit separators of other types illustrated inFIG. 5A.

As illustrated inFIG. 6A, for example, when a user presses “2”, “5” and “0” of the numeric keypad20(seeFIG. 1) to input “25000000”, the CPU11of the scientific calculator1displays “25000000” on the display10(Step S16). When the STO key27is pressed to perform the Store operation (Step S8: YES) and key of “A” among the VARIABLE keys26is pressed (Step S9: YES), because the mathematical expression is not being currently input (Step S10: NO), the CPU11sets the input numerical value of “25000000” as the variable value of the specified variable in the variable memory163(seeFIG. 2), and performs the display illustrated inFIG. 6Aon the display10(Step S12).

When a user seeing the display wants to display the numerical value with the digit separator, a user can perform the setting operation related to the existence of the digit separator in this embodiment (Step S20). In the setting operation related to the existence of the digit separator, when a user presses the SHIFT key23and then presses the MODE SETUP key22(seeFIG. 1) (Step S20: YES), the list of various modes is displayed as illustrated inFIG. 6B. When the user moves the cursor (not illustrated inFIG. 6B) downward to select “3: Separator”, an ON/OFF list of the separator mode is displayed, as illustrated inFIG. 6C, in this case (Step S21). A user can select “1: On” to perform the operation to set “the display with the digit separator”.

The CPU11then performs setting so that the variable values of the variables are displayed with the digit separator or without the digit separator, depending on the setting of the existence of the digit separator, the setting being selected and set by the user operation as described above (Step S22). Concretely, when the display with the digit separator (i.e. “On”) is selected and set as described above, depending on the setting of the display with the digit separator, the variable value of variable “A”, which has been displayed without the digit separator, like “25000000”, is displayed with the digit separators, like “2,50,00,000” (seeFIG. 6D), according to the digit separator type corresponding to country “India” among the digit separator type information162(seeFIG. 5A) because “India” is previously set as the country information161(seeFIG. 5B) stored in the storage section16(seeFIG. 2) in this case.

In this state, when a user presses keys of “1”, “2”, “3”, “4” and “0” of the numeric keypad20to input “1234000000” and performs the Store operation to set the input numerical value as the variable value of variable “C”, the CPU11sets the input numerical value “1234000000” as the variable value of variable “C” in the variable memory163(seeFIG. 2), and displays it with the digit separators on the display10, like “1,23,40,00,000”, as illustrated inFIG. 6E(Step S12).

Moreover, for example, if a user executes the variable Recall batch display processing (Steps S1to S7ofFIG. 3) to display the list of the variable values of the variables at that time, the CPU11retrieves the variable values of the respective variables from the variable memory163, and display the list of the variable values of the respective variables with the digit separators, as illustrated inFIG. 6F.

Meanwhile, as illustrated inFIG. 6K, a user can perform the operation to set “the display without the digit separator” by pressing the SHIFT key23and then pressing the MODE SETUP key22to select “3: Separator” from the displayed list by the SETUP function (seeFIG. 6B), and selecting “2: Off” among the ON/OFF list displayed by the CPU11(Step S21; seeFIG. 6C), in this embodiment (Step S22).

Thus, in this embodiment, a user can select and set “On” or “Off” to execute the setting of “with the digit separator” or “without the digit separator”. When the setting of “without the digit separator” (i.e. “Off”) is executed as described above, the CPU11changes “2,05,16,48,400” displayed with the digit separators, which is the calculation result of CY and the variable value of variable “D”, into “2051648400” displayed without the digit separator, depending on the setting.

Furthermore, when a user presses the SHIFT key23and then presses the STO key27to execute the variable Recall batch display processing so that the list of the variable values of the variables is displayed at that time, the CPU11retrieves the variable values of the respective variables from the variable memory163, and causes the display section13to display the list of the variable values of the variables without the digit separator, as illustrated inFIG. 6L.

Thus, when a user executes a setting operation to determine whether the variable values of the variables and/or the calculation results are displayed with the digit separator or without the digit separator, the CPU11of this embodiment functions as a digit separator existence setting member which sets whether the variable values and/or the calculation results are displayed with the digit separator or without the digit separator depending on the setting operation. Then, the CPU11as the above-described variable value list displaying member displays the list of the variable values of the variables depending on the setting of the existence of the digit separator set by the digit separator existence setting member (i.e. the CPU11itself) (seeFIGS. 6F and 6L).

According to this configuration, it becomes possible to display the variable values of the variables and/or the calculation results with the digit separators or without the digit separator depending on whether a user wants to display them with the digit separators or without the digit separator. Thus, a user can more easily confirm the variable values of the variables and/or the calculation results. Moreover, because a user can freely set the existence of the digit separator, the scientific calculator1(the mathematical expression input device) can become more convenient for a user.

Incidentally, as illustrated inFIG. 6F, when a user executes the variable Recall batch display processing (Step S1: YES), and then presses, for example, the key corresponding to variable “A” among the VARUABLE keys26(concretely, presses a [(−)] (variable A) key or presses the SHIFT key23and then presses the [(−)] (variable A) key) to specify the variable as illustrated inFIG. 6G(Step S3: YES) while the CPU11causes the display section13to display the list of the variable values of the variables on the display10(Step S2), because the mathematical expression is not being currently input (Step S: NO) in the state before the variable Recall batch display processing (seeFIG. 6E), the CPU11retrieves the variable value of variable “A” from the variable memory163and causes the display section13to display the variable value (“25000000” in this case) of variable “A” with the digit separators, on the display10, because “with the digit separator” is set.

By pressing the left cursor key21, a user can continue the mathematical expression inputting process, the mathematical expression beginning from the valuable “A”. Even when a user forgets whether an exchange rate of India Rupee is set as variable “X” or variable “Y”, the user can confirm that the exchange rate of India Rupee is set to variable “Y” by executing the variable Recall batch display processing again so as to cause the display section13to display the list of the variable values of the variables on the display10, as illustrated inFIG. 6H.

When a user subsequently presses the key corresponding to variable “Y” among the VARIABLE keys26(concretely, presses a [S⇄D] (variable Y) key or presses the SHIFT key and then presses the [S⇄D] (variable Y) key) to specify the variable as illustrated inFIG. 6I(Step S3: YES), because the mathematical expression is being currently input by inputting variable “A” and then pressing the left cursor key (Step S5: YES) at the timing before displaying the list of the variable values of the variables (seeFIG. 6G), the CPU11performs the process to additionally input variable “Y” to currently-input mathematical expression “A” (Step S6) so as to continue the mathematical expression inputting process.

When a user executes the Store operation to set the calculation result of mathematical expression “AY” as the variable value of variable “B”, the CPU11sets calculation result “41565000” of mathematical expression “AY” as the variable value of variable “B”. In this case, as illustrated inFIG. 6I, the display is performed with the digit separators on the display10. Similarly, when the operation is performed to set the calculation result of mathematical expression “CY” as the variable value of variable “D” as illustrated inFIG. 6J, the CPU11sets calculation result “205648400” as the variable value of variable D, and causes the display section13to display the calculation result with the digit separators on the display10.

[Variation 1 of Digit Separator Existence Setting Processing]

In the above digit separator existence setting processing, the case where the country in the country information161is previously set to India is described. This is sufficient in the case that the scientific calculator1(the mathematical expression input device) is used only in India.

However, in the case that the scientific calculator1(the mathematical expression input device) is brought to various countries to be used therein, the configuration which enables a user to set the country is more convenient. In such a case, the configuration where the CPU11can properly set the digit separator type depending on the set country when the user selected the country is more preferably.

In this case, the CPU11is configured to function as a digit separator type setting member which sets, as the digit separator type, a mark or a position of the digit separator(s) for displaying the variable values of the variables and/or the calculation results with the digit separator(s), and to function as a country setting member which sets any one of countries depending on a user operation. The storage section16may be configured to function as a country dependent digit separator type storing member which stores the digit separator type (i.e. the digit separator type information162in this embodiment) by country. The CPU11as the variable value list displaying member may be configured to display the list of the variable values of the variables according to the digit separator type corresponding to the country set by the country setting member (i.e. the CPU11itself) when “with the digit separator” is being set as described above.

In this case, though illustration is omitted, for example, when a user presses the SHIFT key23and then presses the MODE SETUP key22to execute the SETUP function, and when the user selects the country in the executed SETUP function, the CPU11is configured to identify the digit separator type based on the country information161(seeFIG. 5B) stored in the storage section16, and to cause the display section13to display the list of the variable values of the variables and/or the calculation results, according to the digit separator type corresponding to the selected country, on the basis of the digit separator type information162(seeFIG. 5A).

[Variation 2 of Digit Separator Existence Setting Processing]

It is also possible to adopt the configuration where a user directly sets the digit separator type, instead of selecting and setting the country name. Also in this case, the CPU11functions as the digit separator type setting member which sets, as the digit separator type, the mark or position of the digit separator(s) for displaying the variable values of the variables and/or the calculation results with the digit separator(s), by the user operation. Hereinafter, a specific example will be described with reference toFIGS. 7A to 7I.

As illustrated inFIG. 7A, for example, when a user presses keys of “3”, “2”, “5” and “0” to input “3250000”, then presses the STO key27to execute the Store operation, and presses the key of “E” among the VARIABLE keys26, the CPU11sets the input numerical value “3250000” as the variable value of specified variable “E” in the variable memory163(seeFIG. 2), and causes the display section13to display the numerical value on the display as illustrated inFIG. 7A.

After that, when the user, who wants to display the numerical value with the digit separators, presses the SHIFT key23and the MODE SETUP key22so that the SETUP function is executed and the list of various modes is displayed (seeFIG. 6B), and selects “3: Separator” among them, the CPU11causes the display section13to display the list of the digit separator types as illustrated inFIG. 7B, in this case. Then, for example, when the user selects “3: Space (DN)” among them, the CPU11refers to the digit separator type information162(seeFIG. 5A) stored in the storage section16(seeFIG. 2), and performs the display of variable value “3250000” of variable “E”, with the digit separators, by the digit separating method corresponding to the digit separator type of “Space (DN)” in the digit separator type information162, like “3 250 000” as illustrated inFIG. 7C.

Moreover, for example, when the user presses the SHIFT key23and then presses the STO key27to perform the variable Recall batch display processing so that the list of the variable values of the variables is displayed as illustrated inFIG. 7Din this state, the CPU11retrieves the variable values of the variables from the variable memory163, and performs the display of the variable values of the variables with the digit separators, correspondingly to the digit separator type of “Space (DN)”. When a user presses the [cos] (variable E) key to specify the variable as illustrated inFIG. 7E(Step S3: YES) while the CPU11causes the display section13to display the list of the variable values of the variables on the display10(Step S2), the CPU11retrieves the variable value of variable “E” from the variable memory163and causes the display section13to display the variable value (“3250000” in this case) of variable “E” with the digit separators, on the display10, because “with the digit separator” is set.

By pressing the left cursor key21, a user can continue the mathematical expression inputting process, the mathematical expression beginning from the valuable “E”. Even when a user forgets whether the exchange rate of Chinese yuan is set to variable “X” or variable “Y”, the user can confirm that the exchange rate of Chinese yuan is set to variable “X” by performing the variable Recall batch display processing again to display the list of the variable values of the variables on the display10, as illustrated inFIG. 7F.

When a user subsequently presses the key of “X” among the VARIABLE key26(concretely, presses a [)] key (variable X) or presses the SHIFT key23and then presses the [)] key (variable X)) to specify the variable, the CPU11performs the process to additionally input variable “X” in currently-input mathematical expression “E”, as illustrated inFIG. 7G. Then, when the user executes the Store operation to set the calculation result of mathematical expression “EX” as the variable value of variable “F”, the CPU11sets calculation result “54018250” of mathematical expression “EX” as the variable value of variable “F”, and causes the display section13to display the calculation result with the digit separators, correspondingly to the digit separator type of “Space (DN)”.

In the case that the user wants to change the digit separator type to be displayed at this time, similarly to the cases ofFIGS. 7B and 7C, when the user presses the SHIFT key23and then presses the MODE SETUP key22, selects “3: Separator” from the displayed list of various modes by the SETUP function, and selects, for example, “1: Comma” from the displayed list of the digit separator types illustrated inFIG. 7B, the CPU11refers to the digit separator type information162(seeFIG. 5A) stored in the storage section16(seeFIG. 2).

The CPU11then causes the display section13to display calculation result “54018250”, by the digit separating method corresponding to the digit separator type of “Comma” among them, with the digit separators corresponding to the digit separator type of “Comma”, like “54,018,250”, as illustrated inFIG. 7H. In this case, when the variable Recall batch display processing is executed, the list of the variable values of the variables is displayed, with the digit separators corresponding to the digit separator type of “Comma”, as illustrated inFIG. 7I.

According to the configuration of Variation 2, a user can display the variable values of the respective variables and/or the calculation results with the intended type of the digit separator, and the scientific calculator1(the mathematical expression input device) becomes convenient for a user.

Although some embodiments and variations of the present invention are described above, the scope of the present invention is not limited to the above embodiments and variations and includes the scope of the invention of the claims and the scope of equivalents thereof.