# for loop for matrix

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I CHUN LIN on 11 Aug 2020
Answered: hosein Javan on 11 Aug 2020
Hello everyone, I have 3 matrix:
x = [1, 2, 5];
y = [0.1, 0.5, 10];
z = [10 20; 30 40];
and one output:
a = z./x + z./y
I want to get the result:
a = 10/1 +10/0.1 = 110, a = 20/1 +20/0.1 = 220
a = 10/2 +10/0.5 = 25, a = 20/2 +20/0.5 = 50
a = 10/5 +10/10 = 3, a = 20/5 +20/10 = 6
a = 30/1 +30/0.1 = 330, a = 40/1 +40/0.1 = 440
a = 30/2 +30/0.5 = 75, a = 40/2 +40/0.5 = 100
a = 30/5 +30/10 = 9, a = 40/5 +40/10 = 12
that is,
a = [110, 25, 3; 220, 50, 6; 330, 75, 9; 440,100,12]
I tried this by for loop
clear
clc
for x = [1; 4; 6; 7; 8; 9]
for y = [13; 26; 45; 62; 70; 89]
z = [0.1 0.01; 0.01 0.1];
a = z./x + z./y
end
end
but getting "Matrix dimensions must agree."
How can I solve this problem? Thank you very much!
##### 1 CommentShowHide None
for element wise division of matrix, dimensions of both matrix must be same. in your case z in 2 * 2 matrix and x is 6 * 1 matrix and y is 6 * 1 matrix.

hosein Javan on 11 Aug 2020
x = [1, 2, 5]
y = [0.1, 0.5, 10]
z = [10 20; 30 40]
X = repmat(x,[4 1])
Y = repmat(y,[4 1])
Z = repmat(z(:),[1 3])
a = Z./X + Z./Y