MaplePrimes - answers and comments on Question, Export plot data

VBA

PatrickT — Tue, 21 Jul 2009 21:26:47 Z

Robert Israel once made the

PatrickT — Tue, 21 Jul 2009 21:40:26 Z

Robert Israel once made the following suggestion, which I have tested and it works:

Tested on : Windows Vista / Maple 13 / Classic GUI

You must first create a directory c:\tmp (or whatever).

restart:
with(plots):

P:= plot3d(x^2+y^2,x=0..1,y=0..1):

A:= op([1,3],P):
a,b:= op(op([1,1],P)):
c,d:= op(op([1,2],P)):
m:= rhs(rtable_dims(A)[1]):
n:= rhs(rtable_dims(A)[2]):
for i from 1 to m do
 for j from 1 to n do
   X:= ((m-i)*a + (i-1)*b)/(m-1);
   Y:= ((n-j)*c + (j-1)*d)/(n-1);
   fprintf("c:/tmp/myfile.txt",
       "%f  %f  %f\n",X,Y,A[i,j]);
 end do
end do:
close("c:/tmp/myfile.txt"):

Thank you!

femarkus — Wed, 22 Jul 2009 11:05:52 Z

Dear Robert and Patrick,

Thank you very much for helping me and providing these two solution tricks.

I will immedeately try them out!

Have a nice day!

Markus

data

Robert Israel — Wed, 22 Jul 2009 00:50:17 Z

It's not necessary to create the directory: I'm just assuming you want to put the file into some directory somewhere (probably one that you already have).

In this case there's no reason to extract the data from a plot, especially since plot (as opposed to plot3d) does not divide the interval into equal subintervals. You can do something like this:

> outfile := "c:/tmp/myfile.csv":
   for i from 350 to 1500 do
      fprintf(outfile, "%d,%f\n", i, n(i)); 
   end do:
   close(outfile);

The resulting .csv (comma-separated values) file should be readable by any version of Excel (or any other modern spreadsheet, for that matter)..