For loop with subs

Hi All,

I have been trying to to have three different matrix based on the values of y , z, however, it's strange, the output matrix of mat is not 1*3 its 4*9 ?

Why can not I have three different matrices (1*3)?

syms l1 l2 real;
x=[2,3,4];
mat=[1 2 3;l1 2 l1];
mat=subs(mat,{l2})
for i=1:3
    y=x(i)+1;
    z=[1 2 3;4 5 y];
    subs(mat,{l1,l2},{y,z})
end 

[Walter Roberson]

Why would you expect the result of substituting into a 2 x 3 matrix to ever be smaller than 2 x 3?

[Ali Tawfik]

Hi Walter,

Thanks for your reply.

I did not say I expect matrix smaller than 2* 3, I said, I would expect the same size, however, the output result is different and bigger ?

So could you please help me ?

Thanks

Answer 1

[TADA]

You are setting a 2x3 matrix into l2, which duplicates mat for all possible substitutions

2x3 times 2x3 = 4x9