surface.hlp.htm

Surface Plot 
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surface Var1 Var2 Var3 , saving(string) round(#) orient(string) 
nowire


Description
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The function attempts to draw a wireframe plot from three variables.
Var1 specifies the x-coordinate, var2 the y-coordinate and var3 the 
z-coordinate. Alternatively the function can draw a circle at each 
point and add a straight line going 
down to the lowest point.

This function can handle data that is not in the form of a matrix of values.
However if there are too many x- and y- values the function will attempt 
to round the dataset values into a more reasonable spread of values. This 
will result in very messy figures. However in s uch a case it is the 
impression that is needed. Many otehr statistical packages require a full 
matrix of values. This is not a problem for the nowire option.

At present the state of rotating the diagram is limited to interchanging the 
axes.

Options
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saving(filename) this will save the resulting graph in filename.gph.
If the file already exists it is DELETED and the new graph will be saved.

nowire this suppresses the drawing of the wire frame in exchange for lines 

round(), data is automatically rounded if there are too many x and y 
values. This option controls the amount of rounding, for example round(1) 
rounds the x and y values to the nearest integer.

orient() this function must take the letters xyz or a combination of them.
Whichever letter comes first is the x-axis, second is y-axis and third is 
the z-axis. Thus orient(zxy) means that var1 is now the y coordinates, var2 
is the z-coordinates and var3 is the x-coordinates. This is different from 
changing the variables around since the wireframe is still draw across the 
original x and y values. This is a crude attempt to implement rotation to 
obtain a clearer picture.

Examples
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surface x y z, saving(myfile) round(10) orient(zxy)