How to update automatically the size of the output array in workspace after each code run?

When i run the code for the first time with the specified condition i get the solution (desiredLLP and desiredPV) which are 1x144 arrays (144 solutions).

If I change the conition in the highlithed if loop and make the interval smaller, I got for example 20 solutions but the problem is that the desiredLLP and desiredPV in workspace don't change their size to 1x20; they keep the size 1x144, so i get the first 20 solutions corrent, and the remaining elements of the array are values from the previous solution unless I delete the arrays manually from workspace before running the code.

This is the first problem. The second one, if i make the condition " if LLP(m)==0.5 "or any other value which is whithin the limits, I get the error "Undefined function or variable 'desiredLLP' " It worls only with the condition >=, <=, < or >

Answer 1

[Walter Roberson]

desiredLLP = []; desiredPV = [];

before the for m loop.

[ilyes louahem m'sabah]

it gives me empty arrays:

desiredLLP=

[ ]

desiredPV=

[ ]

[Walter Roberson]

Yes, suppose that no entries of LLP were between 0.5 and 0.51 then the arrays are going to come out empty.

Have you considered not using a loop at all?

mask = LLP >= 0.5 & LLP <= 0.51;
desiredLLP = LLP(mask);
deisredPV = Npv(mask);

[ilyes louahem m'sabah]

This code without loop worked perfectly. Would you please explain it?

Thank you very much for your support.

[Walter Roberson]

@ilyes louahem m'sabah

https://blogs.mathworks.com/loren/2013/02/20/logical-indexing-multiple-conditions/?doing_wp_cron=1641696488.9307899475097656250000