help-octave
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Reading text file data into matrices for selective plotting


From: Doug Stewart
Subject: Re: Reading text file data into matrices for selective plotting
Date: Wed, 8 Jun 2011 17:26:31 -0400



On Wed, Jun 8, 2011 at 5:00 PM, usagi713 <address@hidden> wrote:
I did the following:

[XX,YY,ZZ]=meshgrid(x,y,z)
surf(XX,YY,ZZ)

The first line worked without errors, but the second line produced quite a
few errors:

error: invalid value for array property "xdata"
error: set: expecting argument 2 to be a property name
error: set: expecting argument 4 to be a property name
error: set: expecting argument 6 to be a property name
error: called from:
error: C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\surface.m at line
150, column 7
error: C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\surface.m at line
51, column 5
error: C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\surf.m at line
47, column 5
error: __go_draw_axes__: invalid grid data
error: called from:
error:
C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\__go_draw_axes__.m at
line 903, column 8
error:
C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\__go_draw_figure__.m at
line 92, column 3
error: C:\Octave\3.2.4_gcc-4.4.0\share\octave\3.2.4\m\plot\gnuplot_drawnow.m
at line 99, column 5

--

I think that you have to make a 2 dim array the length and width of your x and y, and put the z values in it.

for your example, I would suggest a 20 by 20 array
z(20,20)=0, will make the empty z array, then you should put your z values into this array at the correct location.
Since your data goes from 500 down to .005 you would have to map this to one axes between 1 and 20
and your other axes is all 1e-3 then you would have to map this to the other axes from 1 to 20

Once you have decided on a mapping from your coordinates to the 1-20 ranges and put your data in the proper places in the z(20,20) array then surf should work.

HTH 
doug


reply via email to

[Prev in Thread] Current Thread [Next in Thread]