PLOTTER
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Chapter 1: PLOTTER tutorial

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Starting material

We will create a new file to plot the data from example1.dat :

 
Example data 1 of PLOTTER tutorial   
<Xaxis><Y1 >< Y2 ><  Y3>  
2        4     7    3.1  
3       -2     2   -0.4  
4        6     2    1.5  
9       -1     4    3.5  
15       4     3    9.8  
24       4     3    8.1  
29       3     5    5.6  
34       6*    5    7.2  
46       6*    5    7.2  

plotter example1.dat

as the example1 filestem is used to find example1.plt.

Creation of the steering file

We just need a header ( %PLOTTER ), a GLOBAL statement with the dimensions of the GIF file and a LOCAL section. Finishing with GOLINE we parse the file ( example1.dat ) and END the description.

The 'example1.dat' file looks as follows:

 
Pos.     1         2         3  
123456789012345678901234567890  
Example data 1 of PLOTTER tutorial   
<Xaxis><Y1 >< Y2 ><  Y3>  
2        4     7    3.1  
3       -2     2   -0.4  
4        6     2    1.5  
9       -1     4    3.5  
15       4     3    9.8  
24       4     3    8.1  
29       3     5    5.6  
34       6*    5    7.2  
46       6*    5    7.2  

XVALUE 1 4

and

YVALUE 9 11

As our data file has two headers, we use a

GOLINE 2

statement (go as a line graphic with the 3rd line of first data).

The steering file should now look as follows:

 
%PLOTTER  
GLOBAL  
DIMENSION 100 200   
LOCAL  
XVALUE 1 4  
YVALUE 9 11  
GOLINE 2  
END  

Next steps: Parse the data

We will want to plot all Y values later, but we use only X and Y(1) for the first example. We find a * in column 12 that marks the last two X values as 'invalid'. Therefore, we find as an initial approximation that X varies from 0 to 50, and Y from 0 to 10. Incrementing each with 0.5 gives the two statements

XAXIS 0 50 1

YAXIS 0 10 1

Look at the example - example1.gif shows your first successful plot with PLOTTER, and example1.plt is the steering file for example1.dat :

 
%PLOTTER  
GLOBAL  
DIMENSION 200 400   
LOCAL  
XVALUE 1 4  
YVALUE 9 11  
XAXIS 0 50 1  
YAXIS 0 10 1   
GOLINE 2  
END  

Reference:example1.gif

Reference:example1.dat

Reference:example1.plt