JPS5998273A - Processing system of graph generation - Google Patents

Abstract

PURPOSE:To draw the same desired curve as that described with a curved rule by a person, by giving the function of the conversation with him to a plotter. CONSTITUTION:Experimental data points are inputted with a point position input part 1. A point position display part 2 displays inputted points on a display screen 3. A point position analyzing part 4 analyzes inputted points and transfers a point set to an operating part 5 and a plotting part 8. The operating part 5 generates an interpolating function expression passing each inputted point. A curve describing part 6 uses an interpolating polynomial attained in the operating part 5 to obtain functional points more than normal original data points and connects them with lines to describe an artificial smooth curve on the display screen 3. a deciding part 7 inquires of the operator whether the described curve is a desired curve or not; and if the operator answers with ''YES'', a switch 11 is switched to the plotting part 8. The plotting part 8 describes an attained graph. If the operator answers with ''NO'', the switch 11 is switched to the side of a point operating part 9, and the operator is requested to delete unnecessary points and input dummy points through the operating part 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Description of the field to which the invention pertains The present invention relates to a graph creation processing method, and a graph creation processing method for creating a desired curve graph through interaction between a human and a machine. It is related to.

(2) Description of conventional techniques Some graphing devices are already commercially available. They are all graph titles.

A diagram can be drawn by sequentially inputting the labels, graduations, and scales of the X and Y axes, and the (x, y) coordinate values of the points to be plotted. Although these devices were capable of plotting points, they were inadequate when it came to drawing curves through those points. Conventional graph creation methods for drawing curve graphs include simply connecting plotted points with straight lines, and mechanically applying well-known methods such as the least squares method to draw curves. There was just that. Although the latter method allows a smooth curve to be drawn, depending on the degree of the polynomial, there may be many inflection points, causing the curve to be more wavy than necessary, as shown in Figure 1.

If a low-order Spline function is used, the curve will change gradually, and the differential coefficient will be continuous at each point.

You can draw smooth curves without undulations. This is similar to the curve drawn by the creator of the final rough sketch using a cloud-shaped ruler. However, this becomes a problem when the number of plot points is small, and when you want to draw a dotted curve in FIG. 2, it ends up being wavy like a solid line.

Also, on the point always given by the sought curve, Nu is the neighborhood of "
It is not necessarily a curve that will always pass. For example, in the case of a graph that draws a smooth curve connecting experimental data points, it is often desirable to draw a curve by removing or ignoring points with particularly large errors. When drawing a curve using the 112 power law, if there is a point that deviates significantly from the trend of other points, it will be dragged by it and the curve will deviate significantly from the other points. Therefore, if the error at this point is obviously large due to experimental conditions, such as point a in FIG. 6, this point must be skipped and curve l drawn. In addition, there are cases where you want to draw a curve beyond the range of data points, such as a two-dotted line, where the experimental data is limited to a certain point due to the limitations of the experimental equipment, but based on theoretical inference, it should be more than this.

In any case, use some kind of curve approximation formula mechanically.

Since it is rather rare that a desired curve can be obtained by uniform application, a graph creation method is needed that focuses on how to reflect the intention of the graph creator in the 1% correction method. However, this type of method has not been available in the past.

(3) Purpose of the Invention In order to solve these drawbacks, the present invention provides a drawing machine with a human interaction function, and uses this function to allow the human to tell the machine the passing position of the curve or straight line that the machine wants to draw, and the data points. From K, teaching how to process etc.

The purpose is to be able to draw a desired curve or straight line, and the drawings will be described in detail below.

(4) Description of structure and operation of the invention FIG. 4 shows an example of the structure of the present invention, in which 1 is a point position input section, 2 is a point position display section, 3 is a display screen, 4 is a point position analysis section, and 5 is the calculation section, 6
is a curve (or straight line) drawing section, 7 is a judgment section, 8 is a drawing section,
9 is a point operation section.

10.11 is a switch. Note that a straight line is considered to be a special form of a curved line, and in the following, the term curved line will also include a straight line.

The operation of this embodiment will be explained by taking as an example an experimental data graph which is the most common among this kind of "curve graph". Note that a graph that connects two points with a straight line is called a "line graph," and a graph that connects two points with a smooth curve is called a "curve graph." To operate this, first, experimental data points are input using the point position input section 1. There are various ways to do this. You can input numerical values for data points according to the Y-axis and Y-axis settings of the graph you want to draw, read the X and Y values directly from the rough drawing using a digitizer, or use the cursor or light ben on the CRT screen. There are many ways to enter information, etc. Point position display section 2
For the data points input as above, use symbols such as ○, ×, Δ.

It is displayed on the display screen 6.

The point position analysis section 4 analyzes whether the input points are raw data points or dummy points, and passes each point set to the calculation section 5 and drawing section 8.

The point set passed to the plotter 8 is a set of raw data points.

The point set provided in the arithmetic unit 5 consists of (1) points erased using the point operation unit 9 and + (tri) from the entire set consisting of raw data points and one dummy point; This is a point set excluding one input dummy point and a raw data point having the same X coordinate.The calculation unit 5 generates an interpolation function formula that passes through each input point.The interpolation function formula is based on the least squares method. Approximate polynomial based on.

There are Bezier's formula, 5line function, etc.
A cubic 5-line function is best. Since it is a curve that connects cubic curves, there are fewer unnecessary curves.

Moreover, since the differential coefficients are continuous at all points, a smooth curve can be obtained. When the error in the raw data is large, the least squares method is applied to each (Xl, Yi) to find a more probable (X'i, Yi), and this can be interpolated using the Spline function described above.

The curve drawing unit 6 uses the interpolation polynomial obtained by the calculation unit 5 to draw function points (x) which are more than normal raw data points.

f (Xl') is determined, and a pseudo-smooth curve is drawn on the display screen 3 by connecting them with a straight line. Judgment Department 7 welfare.

The operator is asked whether the obtained curve is the desired one, and when the operator's reply is "YB8", the switch 11 is switched to the drawing section 8 side. The drawing section 8 uses an XY grocer, pen recorder, etc.

Draw the obtained graph. Note that, as described above, plotting of data points is performed only for raw data points, and plotting of single dummy points is not performed. When the operator's answer is "NO", the switch 11 is switched to the point operating section 9 side, and the operator is requested to delete unnecessary points and input a dummy point via the point operating section 9.

The operator processes five lines according to the following procedure.

For example, for the raw data points (○ marks) in Figure 5 (al),
Assume that a solid curve is obtained by basic calculations.

The two points a, b, and c in the figure include experimental errors, so if you do not want the two curves to pass over these points.

For example, input points A and B as one dummy point, and then point again.

Delete C. Note that two points A have the same X coordinate value as point a. The point position analysis unit 4 calculates the five points a according to these instructions.
, b, c and raw data points except for point A.

A point set consisting of B is output to the calculation unit 5. The calculation unit 5 is
An interpolation function formula passing through each point on this set is generated and passed to the first curve drawing section B to draw a curve on the display screen 3.

In this way, the solid line shown in FIG.

"NO" and delete/add points again via the point operation unit 9 according to the above procedure.The interpolation function formula generated by the calculation unit 5 gives a smooth curve passing through each given point. Therefore, by repeating the above nine steps, the desired curve can be definitely reached.

It goes without saying that it is extremely easy to draw a curve outside the range of raw data points using the method of the present invention, and all you need to do is add a dummy point to the part you want to draw.

If you still want to draw a straight line, you can remove unnecessary points by following the 2-line method, leaving 2 points that should pass through 5, and connect them. It doesn't matter which one you tie.

The error in the raw data is significant, and the method of calculating the Spline function after applying the -# least squares method does not necessarily pass over one dummy point. However, by repeating this operation several times, it becomes possible to predict the trend, so it is not so difficult to draw a desired smooth curve even in this case.

In addition to the "unnecessary point deletion/dummy point addition method" mentioned above, there is also the "curve sweep method" for changing/correcting curves.

A method such as "curve complete specification method" may be considered. In the "curve sweep method", raw data points near the unsatisfactory portion of the initially obtained curve are selected via the point operation section 9.

and specify the movement range of that point. The calculation section 5 is.

The selected points are sequentially moved at appropriate intervals within the movement range, and interpolation function expressions are generated for each of them. The curve drawing section 6 draws curves one after another on the five display screens based on the information. Among the curves thus swept, a desired one is selected using the determining section 7 and outputted to the second drawing section 8. There may be a plurality of selected points. 9 in "curve complete specification method"
Using the point position input unit 1, in addition to the raw data points, a set of points for determining a curve, which is independent of the raw data points, is input. The arithmetic unit 5 calculates this “
Find the interpolation polynomial using only the curve decision points.

The raw data points are drawn on the display screen 39 by the drawing section 8.

It is not used at all in curve calculations from the beginning. Changes and corrections to the curve are made by adding or deleting curve determination points or by sweeping.

(5) Description of Effects As explained above, according to the present invention, a desired curve can be drawn in the same way as a human being can draw with a cloud-shaped ruler, making it possible for the first time to mechanize the fine-printing of data drawings, etc. Depending on the number of data points, use a drafting pen to draw a curve graph 1.
It takes an average of 1 hour to copy a sheet manually, but in the case of the present invention, the speed can be increased by mechanization, and corrections can be easily made on the display screen, so it is different from manual copying. The psychological burden of ``It's hard to fix a mistake'' is eliminated, and drawing creators can be freed from the trouble of drafting drawings. Furthermore, by combining it with a storage device, drawing data can be saved, and once a drawing is created, it can be taken out and used at any time. The effects of mechanization are immeasurable, as it makes it possible to add and modify data, and to enlarge and reduce printed drawings.

[Brief explanation of the drawing]

FIGS. 1 and 2 are explanatory diagrams illustrating how a curve is drawn by a conventional graph creation method, and FIG. 6 is an explanatory diagram showing an example of a desired curve in an experimental data graph. FIG. 4 is a block diagram showing a configuration example of the present invention, and FIG. 5 is an explanatory diagram illustrating the procedure for obtaining a desired smooth curve in the present invention. 1... Point position input section, 2... Point position display section, 3...
・Display screen, 4... Point position analysis section, 5... Calculation section, 6
... Curve drawing section, 7... Judgment section, 8... Drawing section,
9... Point operation section, 10.11... Switch, a, b
,c...Raw data points. A, B... one dummy point, e... curve. Patent Applicant: Nippon Telegraph and Telephone Public Corporation Patent Attorney Mori 1) Hirote E Figure tz Figure

Claims (1)

[Claims] A raw data point position input unit, a calculation unit that generates an interpolation function formula passing through the points of a given point set, a curve drawing unit that calculates a predetermined number of function points from the interpolation function formula and connects them with a line, and a curve drawing unit that draws the curve. A display screen to be displayed, a determination unit that inquires of the operator whether the obtained approximate curve is the desired one, and a point processing unit that enables addition and deletion of desired points on the display screen;
A graph creation processing method characterized by making it possible to obtain a curve that cannot be taken at the position of raw data points by temporarily erasing or adding data points.