Creating new variable in a subfunction .m file

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Here's the case, I have one main matlab file (main.m) and another sub matlab file (sub.m)
And I need to loop over main.m multiple times to execute sub.m, is it possible to create a new array containing the output of the sub.m? Or I must have a global variable declared and include it in the function
Let this be the case:
First loop:
A=[1 2 3 4 5];
Second loop:
A=[2 8 5 9 6];
Nth loop:
A=[x x x x x];
I need to create an array in the subfunction so that it is able to recognize and store all the maximum of As in the loop
Max_A=
5
9
.
.
N

Accepted Answer

Shameer Parmar
Shameer Parmar on 20 Jun 2016
file 1
function main()
% your code
for loop for calling the sub () for N number of time
% your code which calculating the following 1x5 array.
% A = [1 2 3 4 5] % this is just example
% now pass this array as input to sub () like
max{i} = sub(A).....% here you passing A array to sub() and it giving you max value which store into another array max.
end of for loop.
file 2
% following code for sub()
function output = sub(inputArray)
output = max(inputArray);
% end of function sub()
So in this way you are calling sub function for N number of time and all time it giving you max value which store into new aray Max, so at the end you will get all max values in variable Max.

More Answers (1)

per isakson
per isakson on 20 Jun 2016
Edited: per isakson on 20 Jun 2016
No globals needed. Try
%%in main
R = nan( N, 5 ); % pre-allocate memory
for jj = 1 : N
R(jj,:) = sub();
end
I don't get the last part. Why not simply add after the loop
max_A = max( R, 2 );
  3 Comments
per isakson
per isakson on 20 Jun 2016
Edited: per isakson on 20 Jun 2016
"instead of overwriting each other" &nbsp the code I proposed doesn't overwrite.
If the problem is that R outgrows the physical memory (RAM), then you need to store to a file.
per isakson
per isakson on 20 Jun 2016
Edited: per isakson on 20 Jun 2016
  • "particular function" &nbsp I assume that's sub
  • Is max values from previous calls used in sub? If so, sub has state. You could use a persistent variable to keep previous max values. However, there must be a better way.

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