multidimensional matrix optimization error

3 views (last 30 days)
Hello everyone,
I have an optimization variable
y=optimvar('y',[4,1],'Type','integer','LowerBound',0,'UpperBound',1);
and I want to put this "y" into a matrix which have 4 time periods, so i created a multidimensional matrix as this:
yi=y([ 1 2 3 4; 2 2 3 4;3 3 3 4;4 4 4 4]);
yi(:,:,2)= y([ 1 2 3 4; 2 2 3 4;3 3 3 4;4 4 4 4]);
yi(:,:,3)= y([ 1 2 3 4; 2 2 3 4;3 3 3 4;4 4 4 4]);
yi(:,:,4)= y([ 1 2 3 4; 2 2 3 4;3 3 3 4;4 4 4 4]);
where the third dimension is about time, which I have 4 years in my problem. While I run this code in matlab it says this is an illegal assignment, could anyone help me with that?
Thank you!
  4 Comments
BOWEN LI
BOWEN LI on 21 Jul 2019
thank you again for your answer!
let me try to make this clearer, basically i have y1 y2 y3 and y4, which are binary decision variables (0 or 1). And i create these y1 - y4 by optimvar which will be used in a optimization toolbox.
Also, y1 - y4 are originally all equal to 0,then at some point (in year 1, year 2, year 3, year 4) they turn to 1. So i have to make a third dimension which is about time.
And the matrix has to be in the form below, that y1 - y4 has to be in their specific position shown in the matrix.
yi = [y1 y2 y3 y4
y2 y2 y3 y4
y3 y3 y3 y4
y4 y4 y4 y4]
So in order to add a third dimension that is to make a three dimensinal matrix, i'm wondering how. First of all, I tried to make yi a 3D matrix, that does not work with optimvar. Then, i made y1 - y4 3D dimensional optimization variables, and put them according to the loayout of matrix yi.
Sorry for any misunderstandings, I sometimes need to review a lot to make these things clear. Thank you!

Sign in to comment.

Accepted Answer

Kavya Vuriti
Kavya Vuriti on 24 Jul 2019
Hi,
From the question I understand that you created an optimization variable y and wants to create a 3-dimensional matrix yi in a specific layout where the 3rd dimension is time.
Try using the following code:
y=optimvar('y',[4,1,4],'Type','integer','LowerBound',0,'UpperBound',1);
yi=[y(1,1,1),y(2,1,1),y(3,1,1),y(4,1,1);y(2,1,1),y(2,1,1),y(3,1,1),y(4,1,1);y(3,1,1),y(3,1,1),y(3,1,1),y(4,1,1);y(4,1,1),y(4,1,1),y(4,1,1),y(4,1,1)];
yi(:,:,2)=[y(1,1,2),y(2,1,2),y(3,1,2),y(4,1,2);y(2,1,2),y(2,1,2),y(3,1,2),y(4,1,2);y(3,1,2),y(3,1,2),y(3,1,2),y(4,1,2);y(4,1,2),y(4,1,2),y(4,1,2),y(4,1,2)];
yi(:,:,3)=[y(1,1,3),y(2,1,3),y(3,1,3),y(4,1,3);y(2,1,3),y(2,1,3),y(3,1,3),y(4,1,3);y(3,1,3),y(3,1,3),y(3,1,3),y(4,1,3);y(4,1,3),y(4,1,3),y(4,1,3),y(4,1,3)];
yi(:,:,4)=[y(1,1,4),y(2,1,4),y(3,1,4),y(4,1,4);y(2,1,4),y(2,1,4),y(3,1,4),y(4,1,4);y(3,1,4),y(3,1,4),y(3,1,4),y(4,1,4);y(4,1,4),y(4,1,4),y(4,1,4),y(4,1,4)];
Hope it works.
For more information on creating multi-dimensional binary optimization variables, you can refer the following link: https://www.mathworks.com/help/optim/ug/optimvar.html#mw_cedf0526-03c6-46b9-aba3-a694d89d1003
  1 Comment
BOWEN LI
BOWEN LI on 24 Jul 2019
Thank you so much! I will try with yours. Appreciate for your answer.

Sign in to comment.

More Answers (0)

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!