Re: Easy about Matrices

[Peter Bodin]

> Hi,
>
> Imagine this:
>
> x = [1,2,3,4;5,6,7,8]
> y = [-0.1,0,7,4;-1,-1,2,7]
>
> y(1,1) = -0.1
>
> as it's negative, I have to plot x(1,1) in one color.
>
> y(1,3) = 7 is positive then I plot x(1,3) in other color.
>
> What I've also tried to do is to divide the plotting window with a
> line
> (above it are the positive values, and under the negative ones) and
> give
> different a background color to each part, but I think that is a
> question
> more for the gnuplot mailling list :)
>
> thanks!
> Alvaro.
>
>
>
>
> How about
>>
>> >> find(ismember(X,Y))
>> ans >
>> 2
>> 3
>> 4
>> 6
>> 9
>> 10
>> 11
>>
>> provided that you have the functions from octave-forge.
>>
>> HTH
>>
>> PB
>>
>>
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>>
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>>
>

This might help

clear;
x = [1,2,3,4;5,6,7,8]'
y = [-0.1,0,7,4;-1,-1,2,7]'
yp=yn=y(:);
yp(yp>0)=NaN;
yn(yn<0)=NaN;
plot(x(:),[yp yn],'.')


HTH

PB



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Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
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