JP3309115B2 - Graph display control device and graph display control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a graph display control device having a graphic drawing function and a graph display control method .

[0002]

2. Description of the Related Art Conventionally, for example, a small electronic calculator having a function calculating function has been put to practical use equipped with a graph display device capable of displaying a graph based on an input function formula.

In such an apparatus, when a graphic display is performed, the coordinate range of the X and Y coordinates on the display screen is determined by the user by setting the Min / Max value on the X-axis side and the Min / Max value on the Y-axis side. By inputting the Max value and specifying, the difference between the specified Min / Max values is divided by the number of horizontal and vertical pixels (dots) on the display screen, respectively, so that the X-axis and Y-axis The coordinate pitch per dot is calculated.

That is, based on the X and Y coordinates given at each coordinate pitch calculated as described above, for example, the Y coordinate value when the X coordinate value for each display dot is input to the input function formula Is calculated and sequentially displayed, a graph is displayed. In this graph display state,
When the graph trace is executed, an arbitrary display dot on the graph is displayed as a point, and the X and Y coordinates of the display point are displayed.

FIG. 7 is a diagram showing a trace display state of a function graph by a conventional graph display device. Here, the coordinate range on the X-axis side is designated by (−5 to 5), and the coordinate range on the Y-axis side is designated by the user (−6 to 6). The coordinate pitch calculated according to the designated coordinate range , A graph is displayed according to the X and Y coordinates of each dot, and a point on the graph and its point coordinates are displayed by executing a graph trace.

In this case, since the coordinate pitch obtained by dividing the designated coordinate range by the number of pixels in the X direction is almost an indivisible fraction, the X coordinate of each display dot is substituted into a function expression, and Y
Calculating the coordinates and displaying them in a graph is not only difficult to handle, but the point coordinates displayed when executing the graph tracing have an unnecessarily large number of digits and are very difficult to see.

In executing the graph tracing, a point on the graph can be moved by operating a cursor key. However, no point is displayed in a range where the graph is out of the display screen. Is not performed, and the current trace position is completely unknown.

[0008]

Therefore, the conventional graph display device has the following first to third problems as described below. First, the coordinate pitch per display dot calculated for a coordinate range specified by the user is hardly divisible by the number of display pixels, and the number of digits of numerical values in the calculation processing in graph display is difficult to handle. There's a problem.

Second, since the coordinate pitch itself has a large number of digits and is difficult to handle, the X and Y coordinate values displayed corresponding to the point display at the time of executing the graph trace have more digits than necessary. There are many very elusive problems.

Third, there is a problem that, when executing the graph tracing, the trace position is completely unknown in a range where the graph is out of the display screen. The present invention has been made in view of the above problems, and a first object of the present invention is to enable a graph display process to be easily performed without setting a coordinate pitch having a large number of digits in a coordinate range designated by a user. First graph display control device and first graph display system
It is to provide a control method .

A second object of the present invention is to provide a second graph display control device capable of displaying a point coordinate value with an easy-to-see digit number without setting a coordinate pitch having a large number of digits when executing a graph trace. And second graph display control method
Is to provide a law .

A third object is to execute graph tracing even when the graph is out of the display screen.
It is an object of the present invention to provide a third graph display control device and a third graph display control method capable of displaying a trace position.

[0013]

A first graph display control device according to the present invention includes a graph display image provided on a display unit.
A display control device for displaying a graph on a surface, the grayed
Rough display screen coordinate range (Xmin, Xmax) (Ymin,
Ymax), and a coordinate pitch (Δx) (Δ) per dot on the graph display screen.
y), a coordinate pitch calculating means for calculating the value of the coordinate pitch, a digit rounding means for rounding the value of the coordinate pitch calculated by the coordinate pitch calculating means to a designated effective digit, and a coordinate pitch value updated by the digit rounding means A coordinate range resetting means for calculating and resetting the coordinate range of the graph display screen in accordance with the graph range, and displaying a graph on the display unit in accordance with the coordinate range reset by the coordinate range resetting means. and br /> full display control means, characterized by comprising a.

A second graph display control device according to the present invention comprises a graph trace designation means, and a traced graph when a trace is designated by the graph trace designation means with respect to the first graph display control device. The upper point is displayed as the point position , and this displayed
Of the coordinates of the point position displayed on the display unit.
And point display control means .
You .

[0015] A third graph display control device according to the present invention is characterized in that a point position on a graph to be displayed by the graph tracing means is outside the graph display screen with respect to the second graph display control device. to display the mark on the position of the graph display screen corresponding to said point position
Mark display control means .
You .

[0016]

In the first graph display control device, the value of the coordinate pitch calculated according to the coordinate range specified by the user is rounded according to the specified significant digit, and is reset by the new coordinate pitch. A graph is displayed according to the coordinate range.

[0017] In the second graph display control device further, the graph tracing is specified, the conjunction point on the designated grayed <br/> rough is point display, displays the values of the point coordinates Will be done.

In the third graph display control device, when the point display position on the graph is outside the display screen due to the designated execution of the graph trace, the display screen corresponding to the point position to be displayed on the graph is further displayed. The mark will be displayed at the position .

[0019]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an external view showing a graph display device. The apparatus main body 10 of the graph display apparatus is, for example, large enough to be held by a user with one hand.
In front of the display unit 0, a key input unit 11 and a graphic display unit 12 composed of a dot matrix type liquid crystal screen are provided.

An "ON" key 11a for turning on and off the power, a function expression to be displayed as a graph, and the like are input to the key input unit 11, and the graphic display unit 1 is operated.
X axis and Y axis coordinate ranges (Xmin, Xmax)
) Numeric / symbol keys 11b for designating and inputting (Ymin, Ymax), the effective range of coordinate pitch (Δx) (Δy) per one display dot in the coordinate range specified by the user when displaying a graph. The "RR" (Range Round) key 11c for resetting according to the number, the "EXE" key 11d for executing the coordinate range resetting process and the graph display process, and the graphic display unit 12 A "trace" key 11e for executing a graph trace on the displayed graph, and cursor keys "→" 11f and "←" for moving a trace position displayed as a point when the graph trace is executed.
11 g or the like.

The graphic display unit 12 has a liquid crystal display screen of, for example, 63 dots vertically and 95 dots horizontally, and a graph corresponding to a function formula or the like inputted by the numerical / symbol keys 11b is designated or reset by the user. Are displayed in accordance with the respective coordinate ranges of the X-axis and the Y-axis. When a graph trace is performed in response to the operation of the "trace" key 11e, a point is displayed on the graph displayed on the graphic display unit 12. At the same time, the X and Y coordinate values of the point position are displayed.

FIG. 2 is a block diagram showing a configuration of an electronic circuit of the graph display device. The electronic circuit of the graph display device includes a CPU (Central Processing Unit) 20, and the CPU 20 controls the operation of each part of the circuit.

The CPU 20 includes the key input unit 11
And graphic display unit 12, ROM 21 and RA
M22 is connected. The ROM 21 stores in advance a basic system program for operating the graph display device, a graph display processing program for displaying a graph corresponding to a function expression or the like input by a key, and a coordinate range re-generation program. A range round processing program for performing setting, a trace program for performing graph tracing, and the like are stored in advance, and the control operation by the CPU 20 is executed according to these programs.

In the RAM 22, in addition to a key input register, a display register, etc., an Xmin register 22a, an Xmax register 22b for storing and setting the X-axis coordinate range,
Ymin register 2 for storing and setting the Y-axis coordinate range
2c, Ymax register 22d, Δx register 22 for storing and setting the coordinate pitch per display dot in the X direction
e, Y register 22f in which the coordinate pitch per display dot in the Y direction is stored and set; X register 22g, Y register in which the X and Y coordinates of the trace position displayed on the graph when executing the graph trace are stored 22h, and an F register 22i in which numerical data input during the coordinate range resetting process is stored as the number of significant digits of each of the coordinate pitches (Δx) (Δy).

That is, by inputting a function expression or the like to be displayed as a graph with the numerical / symbol keys 11b of the key input unit 11, and inputting the coordinate ranges of the X axis and the Y axis, the minimum and maximum ranges of the X axis are respectively set. RAM
22 are written to the Xmin register 22a and the Xmax register 22b, and the minimum and maximum ranges of the Y axis are respectively set to the Ymin register 22c and the Ymax register 22d.
Is written to.

Here, when the "EXE" key 11d is operated without operating the "RR" key 11c to execute the graph display processing, the Xmin register 22a, X
max register 22b, Ymin register 22c, Ym
The coordinate pitch per display dot is calculated according to the coordinate ranges stored in the ax register 22d, respectively.
The X coordinates corresponding to each display dot in the X-axis direction are substituted into the input formula according to the coordinate pitches Δx and Δy, and the Y coordinates are sequentially calculated. A graph is displayed on the display unit 12.

Next, the operation of the graph display device having the above configuration will be described. FIG. 3 is a flowchart showing a range round process by the graph display device.

FIG. 4 is a flowchart showing a graph tracing process by the graph display device. FIG. 5 is a diagram showing a graph display state accompanying the range round processing and the graph trace processing of the graph display device.

FIG. 6 is a diagram showing a trace mark display state of a graph outside a display range accompanying the graph tracing process of the graph display device. That is, the user inputs a function expression to be displayed as a graph using the numerical / symbol keys 11b of the key input unit 11, and sets the coordinate range (−5
~ 5), input the coordinate range of Y axis (-6 ~ 6),
The minimum range (−5) and the maximum range (5) of the X axis are the Xmin registers 22a and Xma in the RAM 22, respectively.
It is written to the x register 22b, and the minimum range of the Y axis (−
6) and the maximum range (6) are written to the Ymin register 22c and the Ymax register 22d, respectively.

Here, when the "RR" key 11c is operated, the range round process in FIG. 3 is started. First, the numerical / symbol key 11b is operated to adjust the coordinate pitch per display dot. When the number of significant digits is designated and input, for example, "2", the number of significant digits "2" is stored in the RAM.
22 is written to the F register 22i (step S1).
→ S2).

When the "EXE" key 11d is operated, the effective digit "2" of the coordinate pitch is stored in the F register 22i.
Is specified, and the Xmin register 22a,
The X coordinate range stored in the Xmax register 22b (−
5-5) and the Y coordinate range (−6 to 6) stored in the Ymin register 22c and the Ymax register 22d, the X coordinate pitch Δx and the Y coordinate pitch Δy per display dot are given by the following equations (1) and ( It is calculated as shown in 2) (steps S3 → S4 → S5).

Δx = {Xmax (5) −Xmin (−5)} / 94: The number of display dots on the X axis = 0.10638 ... Equation (1) Δy = {Ymax (6) −Ymin (−6) ／/ 62: the number of display dot intervals on the Y-axis = 0.1935 (2) Then, the X coordinate pitch Δx = 0.10638 calculated in step S5 and the Y coordinate pitch Δy =
. Are rounded in accordance with the designated effective number of digits "2" of the coordinate pitch stored in advance in the F register 22i in step S2, and the new coordinate pitch Δx = 0. 11, Δy = 0.19
Is written into the corresponding registers 22e and 22f (step S6).

The new coordinate pitch Δx = 0.11, Δy = rounded according to the designated number of significant digits “2”
When 0.19 is obtained, as shown in the following equations (3) and (4), the minimum range Xmin (= -5) on the X axis and the minimum range Ymin (= -6) on the Y axis are used as references. ,
A new X coordinate range and Y coordinate range are calculated and reset (step S7).

Xmax = Xmin (−5) + 94 × Δx (0.11) = 5.34 Expression (3) Ymax = Ymin (−6) + 62 × Δy (0.19) = 5.78 Expression (4) Thus, the reset X coordinate range (−5 to −5)
5.34) and the X coordinate value and the Y coordinate value for each display dot corresponding to the Y coordinate range (−6 to 5.78) are both given as easy-to-handle numerical values with a small number of digits after the decimal point. By substituting the X-coordinate value for each dot along the X-axis with a small number of digits into a previously input function formula, the corresponding Y-coordinate value can be easily calculated, and a graph as shown in FIG. Will be displayed.

On the other hand, if the number of significant digits of the coordinate pitch has not been written to the F register 22i,
4, it is determined that no digit is specified, and the X coordinate pitch Δx = 0.10638... And the Y coordinate pitch Δy = 0.
1935 are calculated (step S4 → S8).

Then, the number of significant digits is calculated and designated according to the values of the coordinate pitches Δx and Δy (step S).
9). If the number of significant digits has not been written, a predetermined value may be specified.

If the number of significant digits specified in step S9 is, for example, "1", the coordinate pitches .DELTA.x and .DELTA.y are rounded, and a new coordinate pitch .DELTA.x = 0.1, Δy = 0.2 is written to the corresponding registers 22e and 22f (step S10).

Thus, a new coordinate pitch Δx = 0.
When 1, Δy = 0.2 is obtained, a new X coordinate range and a new Y coordinate range are calculated and reset in the same manner as described above (step S7), and each dot along the X axis having a small number of digits is set. By substituting the X-coordinate values of the above into the previously input function formula, the corresponding Y-coordinate values can be easily calculated and displayed in a graph.

On the other hand, after the range round processing in FIG. 3, the “trace” key 11e of the key input unit 11 is displayed in a graph display as shown in FIG. 5, for example.
Is operated, the graph trace processing in FIG. 4 is started.

That is, first, the minimum range Xmi of the X axis
After n (= -5) is read from the register 22a and written into the X register 22g as an X coordinate value corresponding to the initial trace position, this X coordinate value (= -5) is represented by a graph f
Substituted into (x), the corresponding Y coordinate value is calculated and written into the Y register 22h (steps A1, A2).

Here, the Y coordinate value corresponding to the trace position written in the Y register 22h is the minimum range Ymin of the Y axis.
It is determined whether or not the value is equal to or less than the maximum range Ymax of the Y axis. That is, it is determined whether the point on the graph corresponding to the current X coordinate value is within the range of the display coordinate range on the graphic display unit 12. (Steps A3 and A4).

In steps A3 and A4, when it is determined that the point on the graph corresponding to the current X coordinate value is within the display coordinate range, the X and Y coordinate values are displayed and the corresponding graph coordinate is displayed. Is displayed as the current trace position P (step A5).

When the cursor key "→" 11f is operated, the X coordinate value is added and updated in accordance with the X coordinate pitch Δx.
Is operated, the X coordinate value is subtracted and updated according to the X coordinate pitch Δx. Then, a new Y coordinate value is calculated according to the updated current X coordinate value. (Step A6 → A7, A2).

Here, for example, the cursor key "→" 1
If the current X coordinate value updated in response to the operation of 1f is “−
2.69 ”(step A6 → A7), and if the Y coordinate value calculated by substituting this into the graph formula is“ −2.69 ”(step A2), the display coordinate range on the graphic display unit 12 (Steps A3 and A4), the point on the corresponding graph is displayed as the current trace position P together with the display of the X and Y coordinate values as shown in FIG. 5 (steps A3 and A4). Step A5).

Thereafter, the cursor key "→" 11
By operating f, the X coordinate value is updated to “2.30” (Step A6 → A7), and the Y coordinate value calculated by substituting this into the graph formula becomes “−8.12” (Step A6). A2) If it is determined that the value is below the minimum range Ymin (−6) of the Y axis (step A3), as shown in FIG. 6, the X and Y coordinate values are displayed and out of the display coordinate range. The point mark Pm indicating the corresponding point on the graph is displayed along the lower frame of the graph display range (step A8).

On the other hand, when it is determined that the Y coordinate value calculated by substituting the current X coordinate value into the graph formula (step A2) exceeds the maximum range Ymax (5.78) of the Y axis (step A2). A3, A4), along with the display of the X and Y coordinate values, a point mark Pm for indicating a point on the graph outside the display coordinate range is displayed along the upper frame of the graph display range. (Step A
9).

Thus, in the graph tracing, the X and Y coordinate values corresponding to the trace position are displayed in the coordinate range reset according to the coordinate pitch rounded according to the designated significant digit. Trace coordinates can be easily displayed with a small number of digits as necessary.

Further, points on the graph outside the range of the display coordinate range are displayed along the frame of the graph display range as point marks Pm correspondingly indicating the trace positions, so that any trace positions are clearly indicated. Become so.

Therefore, according to the graph display device having the above configuration, the X coordinate pitch and the Y coordinate pitch per display dot calculated according to the X and Y coordinate ranges specified by the user are displayed on the graphic display unit 12. The rounding (RR) process is performed according to the designated number of significant digits, and the coordinate range is reset with a coordinate pitch of a small number of digits. Therefore, the X and Y coordinate values corresponding to each display dot are easy to handle and easy. The graph display processing can be executed, and the X and Y coordinate values on the graph displayed at the time of graph tracing are very easy to see with a small number of digits, and points on the graph that are out of the coordinate range are indicated on the display unit. Since it is displayed as a point mark Pm along the twelve frames, the user can check any trace position.

[0050]

According to the first graph display control device of the present invention, the value of the coordinate pitch calculated according to the coordinate range specified by the user is rounded according to the specified significant digit, and the new coordinates are set. Since the graph is displayed according to the coordinate range reset by the pitch, the graph display process can be performed reliably and easily without setting the coordinate pitch having a large number of digits in the coordinate range specified by the user. Will be possible.

According to a second graph display control apparatus [0051] The present invention further, when the graph tracing is specified, the specified
With a point on the graph is point display, the value of the point position is displayed, upon execution of the graph traces, without often coordinate pitch number of digits is set, the point coordinate values in legible digits Can be displayed.

According to the third graph display control device of the present invention, when the point display position on the graph is outside the display screen due to the designation of the graph trace, it corresponds to the point position to be displayed on the graph. Since the mark is displayed at the position of the display screen, it is possible to confirm and display the trace position reliably and easily even when the graph is out of the display screen when executing the graph trace. Become.

[Brief description of the drawings]

FIG. 1 is an external view showing a graph display device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an electronic circuit of the graph display device.

FIG. 3 is a flowchart showing a range round process by the graph display device.

FIG. 4 is a flowchart showing a graph tracing process by the graph display device.

FIG. 5 is a view showing a graph display state accompanying a range round process and a graph trace process of the graph display device.

FIG. 6 is a diagram showing a trace mark display state of a graph outside a display range accompanying a graph tracing process of the graph display device.

FIG. 7 is a diagram showing a trace display state of a function graph by a conventional graph display device.

[Explanation of symbols]

10: apparatus main body, 11: key input section, 11a: "ON"
Key, 11b: numeric / symbol key, 11c: "RR"
Key, 11d ... "EXE" key, 11e ... "trace"
Key, 11f ... "→" key, 11g ... "←" key, 12
... Graphic display unit, 20 ... CPU (Central Processing Unit), 21 ... ROM, 22 ... RAM, 22a ... Xmin
Register, 22b ... Xmax register, 22c ... Ymi
n registers, 22d... Ymax registers, 22e.
Register, 22f .DELTA.y register, 22g .X register, 22h .Y register, 22i .F register, P .trace position, Pm .point mark.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G06T 11/20 120 G09G 5/00

Claims (6)

(57) [Claims] 1. A graph display screen provided on a display unit.
In the display control device for displaying the rough, the graph display screen coordinates range (Xmin, Xmax) (Y
a coordinate range setting means for setting min, Ymax), and a coordinate pitch (Δ) per dot on the graph display screen.
x) coordinate pitch calculating means for calculating the value of (Δy); digit rounding means for rounding the coordinate pitch value calculated by the coordinate pitch calculating means to a designated effective digit; coordinates updated by the digit rounding means Coordinate range resetting means for calculating and resetting the coordinate range of the graph display screen according to the pitch value; and displaying a graph on the display unit in accordance with the coordinate range reset by the coordinate range resetting means. graphical representation makes
A graph display control device, comprising: control means; 2. A graph trace specifying means, and when a trace is specified by the graph trace specifying means, a point on the traced graph is defined as a point position.
Claim 1 and with make display, characterized in that the point display control hand <br/> stage for displaying the value of <br/> coordinates of the displayed point position on the display unit, further comprising A graph display control device as described in the above. 3. If the point position on the graph to be displayed by the graph tracing means is out of the graph display screen, the mark display control means for displaying a mark at the position of the graph display screen corresponding to said point position 3. The graph display system according to claim 2, further comprising:
Control device. 4. A graph display screen provided on a display unit.
In a display control method for displaying a rough, a coordinate range (Xmin, Xmax) (Y
min, Ymax), and a coordinate pitch (Δ) per dot on the graph display screen.
x) coordinate pitch calculating step for calculating the value of (Δy)
And the coordinate pitch calculated in the coordinate pitch calculating step.
And the coordinate pitch value updated by this digit rounding step.
Calculate the coordinate range of the graph display screen according to
Coordinate range resetting step to set and coordinates reset by this coordinate range resetting step
A graph for displaying a graph on the display unit according to the range
And a display control step . 5. A trace designated on the displayed graph.
The point on the traced graph
As well as the position of the displayed point.
Point display system for displaying the coordinates of the coordinates on the display unit
5. The graph according to claim 4, further comprising:
Display control method. 6. A point position on the graph to be displayed.
Is outside the graph display screen,
Mark at the position on the graph display screen corresponding to the
Mark display control step is further provided.
The graph display control method according to claim 5, wherein