JP2750958B2 - Formula editing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic desk calculator (function calculator) having a function function, and more particularly, to a function calculator for inputting and storing a mathematical expression for calculation. The present invention relates to a formula editing device.

[0002]

2. Description of the Related Art Scientific calculators are known which store a user-defined mathematical expression together with several kinds of predetermined function functions and can repeatedly execute calculations according to the mathematical expression. The mathematical expression is defined by a user inputting using a predetermined key of the calculator. At this time, it is necessary to freely edit the mathematical expression. For this purpose, a device called a numerical editor for editing the mathematical expression is provided.

FIG. 8 is a diagram showing a key operation and a display example of a calculator when editing a mathematical expression using a conventional numerical editor. Referring to the upper row of the table shown in FIG.
The case of inputting the expression "+4456" will be described.

[0004] The user first uses the numeric keypad to set "1".
"2" and "3" are sequentially input. The input is performed on a part called an "cursor", which is underlined to indicate the input position on the display. Each time a character is input, the cursor moves one digit to the right. Next, the user presses the arithmetic expression "+", and then again inputs "4", "5", and "6" using the numeric keypad again. As a result, “123 + 456” is displayed on the display unit of the calculator. The calculator of this example employs a dot matrix display unit, and "+" is also displayed using the dot matrix. When the above input is completed, the cursor is immediately after “6”.

Next, consider a key operation for editing this mathematical expression. For example, consider the case where "+" of "123 + 456" is deleted. First, the user uses the "left shift key"
(Key for moving the cursor to the left by one digit, represented by a black triangle pointing left in FIG. 8) four times. Each time the left shift key is pressed once, the cursor moves one digit to the left. As a result of this operation, the cursor moves to the “+” portion.

Next, the user presses the "delete [DEL] key" once. When the delete key is pressed once, the character at the cursor position is deleted and, at the same time, the character strings on the right side of the cursor are moved one by one to the left (left-justified). Therefore, as a result of the above-described operation, the display becomes “123456”. At the same time, the formula to be entered is also "12345".
6 ". At this time, the cursor is blinking at the position where the deletion process was performed, that is, at the position of “4” after the deletion of “+”.

[0007] In this way, by editing a mathematical expression and writing the desired mathematical expression on the calculator, it is easy to repeat the calculation according to the mathematical expression.

[0008]

However, the above-described formula editing apparatus has a problem that even when a formula is incorrect as a result of an editing operation, it is difficult to find the error. For example, in the case of the example shown in FIG. 8, although "+" was originally deleted in order to change "+" to "-", "-" may be forgotten to be inserted at an appropriate position. In the case of the example shown in FIG. 8, since both before and after “+” are numerical values of three digits, if “+” is deleted and no processing is performed thereafter, these two numerical values are changed. It is interpreted as a 6-digit numerical value "123456" after connection. Needless to say, if this calculation is performed as it is, the calculation will be performed successfully, but the answer obtained will be obviously wrong.

As described above, two numerical values are often interpreted as one numerical value due to the elimination of an intervening operator. Moreover, in this case, the error is not detected as a grammatical error, and the calculation is normally executed with the expression including the error. As a result, even when the formula is incorrect as a result of editing, the calculation is executed as it is, and the obtained answer may not be noticed to be incorrect and may be treated as correct data.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a formula editing apparatus which can prevent a calculation process from being performed while a formula is incorrectly defined as a result of a deletion process.

[0011]

According to the present invention, there is provided a mathematical expression editing apparatus for editing a mathematical expression in a computer capable of storing a mathematical expression defined as a sequence of mathematical elements classified into a plurality of categories. A mathematical formula editing device,
A plurality of formula element storage means each capable of storing one of the formula elements, and selecting one of the formula element storage means to perform one of a plurality of types of editing processing including deletion processing; And a deletion unit for deleting the content of the selected mathematical element storage unit in response to the deletion process being specified by the process specification unit,
In response to the operator specifying deletion processing for the operator, the formula elements stored in the formula element storage means before and after the selected formula element storage means match and belong to the predetermined category. Category match detecting means for detecting that a formula element is not included in a mathematical element in a selected mathematical element storage means in response to an output of the category match detecting means. Separation position explicit information insertion means for inserting explicit information.

[0012]

In the formula editing apparatus according to the present invention, the formula elements constituting the formula are sequentially stored in the formula element storage means. When it is specified by the processing specifying means to select a certain mathematical element storage means and to delete the mathematical element stored therein, the deleting means deletes the contents of the selected mathematical element storage means. The category match detecting means responds to the processing designation means to specify the deletion processing for the operator, and the mathematical elements stored in the mathematical element storage means before and after the selected mathematical element storage means are both together. If it belongs to the same specific category, it is detected and the information is given to the separation position explicit information inserting means. In response to this information, the separating position explicit information inserting means inserts the separating position explicit information at the position of the selected mathematical element storage means.

[0013]

FIG. 1 is a plan view of a scientific calculator provided with a numerical editor, which is an example of a mathematical formula editing apparatus according to the present invention, and FIG. 2 is a block diagram of the scientific calculator. Referring to FIG. 2, this scientific calculator 1 has a CPU (Central Processin) for controlling the entire calculator.
g Unit) 11 and a ROM (Read-On) for storing programs and constants for operating the calculator.
LY Memory 12 and a RAM (Ran) for storing data for controlling the calculator and numerical values to be processed.
dom Access Memory) 13, a display 2 for displaying a set number, a calculation result, a mathematical expression to be set, and the like, a display drive circuit 14 controlled by the CPU 11 to perform drive control of the display 2, And a keyboard 3 for providing a predetermined signal to the CPU 11 in response to a key operation by a user.

Referring to FIG. 1, a display 2 includes a numerical display section 22 composed of a segment display for displaying an input mathematical expression and a calculation result, and a function name (a function name) of a function selected by a user. Function display unit 23 composed of a dot matrix display for displaying “sin”, “cos”, etc.)
And a mode display unit 21 for displaying an operation mode of the scientific calculator 1 such as a normal operation and a mathematical expression storage operation.

The keyboard 3 has a numeric keypad 32 prepared for inputting 0 to 9 and a decimal point, a function key unit 31 prepared for selecting a desired function or operation, and the like. Left shift key 33 for use when moving the cursor, right shift key 34 for use when moving the cursor to the right, key 35 for turning off the power of the scientific calculator 1, and turning on the power of the scientific calculator 1. And a key 36 for

In the function key section 31, in addition to functions such as sin and cos, a left parenthesis key 31a, a right parenthesis key 31b used for inputting a mathematical expression, and other general operations ("+""-" Arithmetic expressions representing “×”, “」 ”, etc.) are provided.

The numerical editor according to the present invention has a ROM 1
2 is loaded into the CPU 11
Is implemented. The CPU 11 performs predetermined processing using the RAM 13 in response to data entered by the user using the keyboard 3 based on the mathematical formula displayed on the display 2, and displays the result on the display 2.
When entering a formula, the elements that make up the formula, such as numbers, functions, and operators (hereinafter referred to as "formula elements"),
The formulas are stored in a predetermined storage area prepared in the RAM 13 in a predetermined format in the order in which the mathematical expressions are formed. CPU11
Edits a mathematical expression by changing the arrangement of mathematical expression elements in the storage area in accordance with a user's instruction.

FIG. 3 is a schematic configuration diagram of a storage area for storing the arrangement of the above-described formula elements. Referring to FIG. 3, this storage area includes a minimum unit 4 of storage area called a plurality of "steps" for storing one mathematical element. In each step, "1""2"
Numerical elements such as “3” and “+” are stored. In the case of the example shown in FIG. 3, "123 + 45" is stored in this storage area.
6 ”is stored.

The CPU 11 edits a mathematical expression by changing the arrangement of mathematical elements stored in the storage area. The position of the mathematical element to be processed is
It is represented by data indicating a current processing position called a data pointer DP. The pointer DP also indicates data corresponding to the position where the cursor is currently set, among the data displayed on the display 2.

When the data pointer DP is at the position shown in FIG. 3, this pointer indicates the mathematical expression element "+". By pressing the delete [DEL] key when the data pointer is at this position, the numerical editor deletes the data "+" stored at this position and moves the data below it upward one by one. Move. By doing so, a blank is prevented from being generated at the deleted position. At this time, in response to each data being moved upward in the storage area, the data displayed on the display 2 is left-justified in order from the deletion position.

As a result of deleting "+", the contents stored in the storage area are as shown in FIG. Referring to FIG. 4, the data stored in the storage area is in the same state as storing one numerical value “123456”. In this state, the calculation is executed with the wrong expression as in the conventional numerical editor, and the error may not be noticed.

Therefore, in the case of the numerical editor according to the present invention, as shown in FIG. 3, it is checked whether or not the mathematical elements stored in the steps before and after the position designated by the data pointer are both numerical values. And taking measures to prevent errors. That is, in the case of the example shown in FIG. 3, since both before and after “+” are numerical data, if “+” is deleted, two numerical values are joined as shown in FIG. Therefore,
In such a case, as shown in FIG. 5, at a position pointed to by the data pointer DP, data called "junction prevention code" for specifying that two numerical values should be separated is inserted. . This joining prevention code
Since it cannot be processed as a normal mathematical expression element, an error will occur if the calculation is performed with the join prevention code included, and an error in the mathematical expression setting will be easily found.

FIG. 6 is a diagram showing a key operation performed in the above-described processing and a display example displayed on the display unit 2.
Referring to the first row of FIG. 6, "1", "2", and "3" are sequentially input using the numeric keypad 32, the "+" key of the function key unit 31 is pressed, and then the numeric keypad unit is again pressed. 32
, "4", "5", and "6" are sequentially input. As a result, the display as shown in the second column of the first row in FIG. It should be noted that, in the case of the scientific calculator having the numerical editor according to the present invention shown in FIG. 1, a matrix display is not used for the numerical display 22 of the display 2, and as a result, 22 means that the function name cannot be displayed. Therefore, the function name is displayed using the dot matrix of the function display unit 23, and only the numeral is displayed on the numerical value display unit 22. In the case of FIG. 6, "+" is displayed on the function display section 23, and "456" is displayed on the numerical value display section 22. The numbers and other function names input prior to the function displayed on the function display unit 23 are not displayed on the display 2 as they are. That is, as a result of performing the key operation as shown in the first row of FIG. 4, only “+456” is displayed on the display 2. Of course, in this case, if the left shift key 33 shown in FIG. 1 is pressed, the left part of the mathematical expression “+” is displayed on the display 2, and if the right shift key 34 is pressed, the further right part of the displayed mathematical expression is displayed. Is displayed on the display 2.

In order to delete "+", the left shift key 33 is pressed once, as shown in the second row of FIG.
With this operation, the cursor is moved to the “+” portion of the function display section 23 on the display 2. In this case, it should be noted that in the case of the numerical editor according to the present invention, the numerical value “4” is set.
56 are all numerical values and “4”
56 "collectively represents one data. Therefore, in the case of the numerical editor according to the present invention,
By pressing the left shift key 33 once, the number “45” is displayed.
The cursor located at any part of "6" can be moved to the part of "+". Of course, each number may be processed as separate data, in which case the left shift key needs to be pressed more.

Subsequently, the user presses a delete [DEL] key to delete "+". As a result, “+” is deleted. However, since the mathematical elements before and after “+” are both “3” and “4”, both of which are numerical values, the two numerical values are separated into the deleted “+” part. A splice prevention code is inserted to indicate what to do. In addition, "-"
If the user inputs, for example, the joining prevention code is replaced with the entered symbol again.

Consider a case where the execution key [=] is pressed while the joining prevention code is still inserted. Since the joining prevention code is a code that is not included in the formula element, the calculator can immediately detect that the formula is incorrect. Then, an error message “Er1” indicating that execution has been specified without an operator is displayed on the display 2. If there is no joint prevention code as before, "+"
By using this numerical editor, there is no possibility that such an error will occur, as compared with the case where two numerical values “123” and “456” are joined and interpreted as “123456” and executed as it is. .

The above functions are realized by a program executed by the CPU 11. Hereinafter, a control structure of a part related to the present invention in the program will be described.

FIG. 7 is a flowchart of a process when the delete [DEL] key is pressed in the scientific electronic calculator having the numerical editor according to the present invention. Referring to FIG.
In step S1, the data stored in the step at the position indicated by the current data pointer DP is deleted irrespective of whether the data is a numerical sequence or other instruction data. As a result of the removal,
The data stored in the steps after the current data pointer DP are sequentially moved upward. That is, the elements constituting the formula are sequentially shifted upward, thereby preventing a step in which no data is present from occurring. As a result of this processing, one digit at the position where the cursor is currently located is deleted from the mathematical elements displayed on the display 2, and the data thereafter are sequentially left-justified.

In step S2, it is determined whether the data stored in the step pointed to by the current data pointer DP is a numerical value. This determination can be made easily by examining the data stored in the step. It should be noted that the data examined in step S2 is the data immediately after the data deleted in step S1.
This is because, as a result of the deletion in step S1, the data after the step indicated by the data pointer DP has been sequentially shifted up one by one. If the answer to the determination in step S2 is YES, control proceeds to step S3, otherwise the process ends. If the answer to the determination is NO, the process ends because the content pointed to by the current data pointer DP is other than a numerical value, and there is no possibility that an error will occur in the formula by joining with the immediately preceding data. is there.

In step S3, the content of the data pointer DP is decremented by one. The control proceeds to step S4.

In step S4, the data pointer D
It is determined whether the data stored in the step pointed to by P is a numerical value. If the answer is YES, control proceeds to step S5; otherwise, control proceeds to step S7.

In step S7, the data immediately after the deleted data was a numerical value, but the data immediately before the deleted data was other than a numerical value.
Therefore, there is no danger that the data before and after the data deleted as a result of the deletion will be joined and changed to other data. Therefore, 1 is added to the contents of the data pointer DP to return the position of the data pointer DP to the original position, and the process ends as it is.

When the process proceeds to step S5, it means that both the values before and after the deleted data are numerical values, so that the numerical values before and after the deletion process are joined and treated as one numerical value. is there. In this case, an error occurs in the result of the arithmetic processing. In order to prevent the two numbers from joining, it is necessary to insert a joining prevention code for specifying the position where the data is deleted at this position. . In step S5, 1 is added to the content of the data pointer DP for that purpose, and the data pointer DP is returned to the position of the step where the deleted data was stored. The control proceeds to step S6.

In step S6, a join prevention code is inserted at the position of the step indicated by the data pointer DP. Then, the process ends.

The joint prevention code inserted at the position where the data is deleted in step S6 is other than the data used as the mathematical formula element. Therefore, even if the calculation is executed while the splicing prevention code is included in the formula, it is possible to discover immediately that the formula contains an error when the splicing prevention code is detected. There is no danger of performing an operation with an incorrect expression and obtaining an incorrect answer.

Although the present invention has been described in detail with reference to the drawings, the present invention is not limited to this.
Various modifications can be made in addition to the above-described embodiment.

[0037]

As described above, according to the present invention, when an operator having a formula is deleted, if the formula elements before and after the formula belong to the same specific category, it is detected. You. In this case, separation position specifying information for specifying the separation position is inserted at the position of the deleted operator. Therefore, if there is a possibility that two mathematical elements before and after the deletion of a certain operator may be combined to be mistaken as one mathematical element, it is easy to confirm that these two elements should be separated from each other. can do. Since the information to be inserted is not included in the mathematical formula element, it is easy to detect an error in the mathematical formula even when the calculation is performed in accordance with the mathematical formula.

As a result, it is possible to provide a numerical value editor capable of preventing calculation processing from being performed while a mathematical expression is incorrectly defined by deletion processing.

[Brief description of the drawings]

FIG. 1 is a plan view of a scientific calculator provided with a numerical editor according to the present invention.

FIG. 2 is a block diagram of a scientific calculator provided with a numerical editor according to the present invention.

FIG. 3 is a schematic diagram of a storage area for storing mathematical elements.

FIG. 4 is a schematic diagram showing a storage area of a mathematical expression element after an operator “+” is deleted.

FIG. 5 is a schematic diagram of a storage area into which a joining prevention code is inserted.

FIG. 6 is a diagram showing a key operation and a display example when editing processing is performed according to a numerical editor according to the present invention.

FIG. 7 is a flowchart of a program executed when deletion processing is selected in the numerical editor according to the present invention.

FIG. 8 is a diagram showing a key operation and a display area when editing processing is performed according to a conventional numerical editor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Scientific calculator 2 Display 3 Keyboard 11 CPU 12 ROM 13 RAM 14 Display drive circuit

Claims (1)

(57) [Claims] 1. A mathematical formula editing apparatus for editing a mathematical formula, wherein the mathematical formula is defined as a sequence of mathematical formula elements classified into a plurality of categories. A plurality of mathematical element storage means capable of storing one of the elements, and an arbitrary one of the mathematical element storage means is selected to designate one of a plurality of types of editing processing including deletion processing to be performed. In response to the designation of the deletion processing by the processing designating means, the mathematical element stored in the mathematical element storing means before and after the selected mathematical element storing means is a predetermined category. And a category match detecting means for detecting belonging to the selected formula element in response to the operator specifying the deletion processing by the processing specifying means. Deletion means for deleting the contents of the storage means; and in response to the output of the category match detection means, the selected formula element storage means specifies a formula element separation position which is not included in the formula element. Formula editing apparatus including separation position explicit information inserting means for inserting separation position explicit information for use.