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Topic: Plotting a line with variables from a matrix
Replies: 9   Last Post: Feb 18, 2013 1:50 PM

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 dpb Posts: 9,850 Registered: 6/7/07
Re: Plotting a line with variables from a matrix
Posted: Feb 18, 2013 10:44 AM

On 2/17/2013 5:16 PM, Vilius wrote:
> three example matrixes:
> V1=1
> A=[10*1 20*1 ; 30*1 40*1]
> a=inv(A)=[ -0.2000 0.1000; 0.1500 -0.0500]
>
>
> V2=2
> A=[10*2 20*2 ; 30*2 40*2]
> a=inv(A)= [ -0.1000 0.0500 ; 0.0750 -0.0250]
>
> V3=3
> A=[10*3 20*3 ; 30*3 40*3]
> a=inv(A)= [ -0.0667 0.0333; 0.0500 -0.0167]
>
> and so on with other Vs
>
> so on the graph (V;a11) : first point (1; -0.20) second point (2; -0.1)
> third point (3;-0.0667) and so on
>
> If I can figure it out how to do this i can write a proper report,
> otherwise it takes too much time to calculate everything seperately.

OK, for a straight-ahead solution try the following...

V=[1:5];
A=reshape([10:10:40],2,2)';
a=zeros(size(A,1),size(A,2),length(V));
for i=1:length(V)
a(:,:,i)=inv(V(i).*A);
end
for i=1:size(a,2)
for j=1:size(a,1)
plot([1:5],squeeze(a(i,j,:)))
pause(1)
end
end

That will leave you w/ a result 3D array from which it selects the
planes to plot one at a time...if your array sizes are really, really,
really large you may have memory problems in which case you may need to
write to file and postprocess them -- but then you may well have numeric
problems anyways w/ inverse.

--

Date Subject Author
2/17/13 Guest
2/17/13 dpb
2/17/13 Guest
2/17/13 dpb
2/17/13 Bruno Luong
2/17/13 Guest
2/17/13 dpb
2/17/13 Vilius
2/18/13 dpb
2/18/13 dpb