For loop element Matrix construction

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I am currently writing an element based analytical program for Uni but have hit a wall. I have a for loop for a set number of elements within which a number of different equations each giving a different aspect of each element. So, for 10 iterations(i) (or 10 elements) i am calculating A(i) B(i) C(i) etc. and i want to put these in one table or matrix related to their element number so the colums are denoted by the element number and the rows have a diferent result in (A,B or C...). What code do i use to do this?

Accepted Answer

Thomas
Thomas on 13 Nov 2012
Edited: Thomas on 13 Nov 2012
This video should help:
You can save the output in a vector or matrix as shown,
Eg:
% Preallocate space for y
y = zeros(1,10);
z = zeros(1,10);
for ii=1:10
y(ii)=ii+rand; % use y(ii) so that it is written as a vector
z(ii)=ii+rand; % use z(ii) so that it is written as a vector
end
out=[y' z'] % output as a matrix

More Answers (2)

Mark
Mark on 13 Nov 2012
Edited: Mark on 13 Nov 2012
I dont quite see how to do it for numerous varibales...Sorry :-s
So my code is:
for i = 1:nbe;
r(i) = (R*xo)+(deltar*(i-1));
x(i) = r(i)/R;
M(i) = x(i)*((Omega*R)/sos);
Theta(i) = Trad0+(x(i)*Trad1);
a(i) = (0.1/(1-M(i)^2))-(0.01*M(i));
v1(i) = ((Omega*a(i)*R*sigma)/16)*(-1+(1+((32*Theta(i)*x(i))/(a(i)*sigma)))^0.5);
phi(i) = atan((v1(i))/(Omega*r(i)));
end
And i want a table or matrix in the form of i against all these variables, one per row...
  2 Comments
Jan
Jan on 13 Nov 2012
I still do not understand the question. Where are "A, B, C, ..." created in your code? Why do you need a loop here? A vectorization would simplify the code.
In general creating "A, B, C, ..." is less efficient than creating a cell "A{1}, A{2}, ...", because the later can processed in a loop directly.
Mark
Mark on 13 Nov 2012
Sorry, the initial question was an example. I used a for loop because when i tried creating it to solve element wise outside of a loop i started getting inner matrix dimensionality issues. Would you suggest a different approach?

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Mark
Mark on 13 Nov 2012
Sorry to be so confusing, ill leave it and do it a slightly different way, thanks though

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