Using a for-loop with several input matrices

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Chris Matthews
Chris Matthews on 17 Apr 2017
Commented: Jan on 18 Apr 2017
I have several matrices that I want to run a for-loop through, and am not sure how to do this.
clc
clear all
TEST1 = [0 0 0 0];
TEST2 = [1, 1, 1, 1];
TEST3 = [235.0623 188.2428 44.9479 103.4551];
l = length(TEST3);
for k = 1:l
y(k) = 0;
if (k==1)
w(k) = 1/sqrt(l);
else
w(k) = sqrt(2/l);
end
for n = 1:l
y(k) = y(k)+TEST3(n)*cos(pi*(2*n-1)*(k-1)/(2*l));
end
y(k) = y(k)*w(k);
end
DCTTEST3 = (y)
My for-loop works well, and is currently programmed to use test3 matrix as the input, and show the corresponding matrix output.
Is it possible, without triplicating the code, to use this format but run the three test cases through it, and then have three output matrices? If it is, can you please show me how?
Thanks in advance! Chris

Answers (1)

Jan
Jan on 17 Apr 2017
TestSet = {[0 0 0 0], ...
[1, 1, 1, 1], ...
[235.0623 188.2428 44.9479 103.4551]};
DCTTEST = cell(1, numel(TestSet)); % Pre-allocate
for iTest = 1:numel(TestSet)
Test = TestSet{iTest};
l = length(Test);
y = zeros(1, l); % Pre-allocate
w = zeros(1, l);
for k = 1:l
if (k==1)
w(k) = 1/sqrt(l);
else
w(k) = sqrt(2/l);
end
for n = 1:l
y(k) = y(k) + Test(n) * cos(pi * (2 * n-1) * (k-1) / (2*l));
end
y(k) = y(k)*w(k);
end
DCTTEST{iTest} = y;
end
  2 Comments
Chris Matthews
Chris Matthews on 18 Apr 2017
Edited: Chris Matthews on 18 Apr 2017
When i look at DCTTEST, it only shows this:
DCTTEST =
[1x4 double] [1x4 double] [1x4 double]
And when I look at each of these vectors, they all only show the answer from the third test case?
Jan
Jan on 18 Apr 2017
Use the debugger to see, what's going on. If this does not reveal the problem, post your code here.

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