# How do i resolve this error

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Olufemi Ologun on 17 Jan 2022
Commented: Rik on 17 Jan 2022
Error using .*
Matrix dimensions must agree.
Error in phdegmninvert (line 97)
up=-(fftbou.*(exp((z0*100000)*(frequencytotal.*(1/100000)))));

Max Heimann on 17 Jan 2022
Edited: Max Heimann on 17 Jan 2022
Try turning the multiplication in the middle into an elementwise multiplication aswell.
Also, the last multiplication probably shouldnt be elementwise since you are multiplying with a scalar value
up=-(fftbou.*(exp((z0*100000) .* (frequencytotal*(1/100000)))));
If that does not work, we would need more information about the dimensions of the multiplied elements.
Olufemi Ologun on 17 Jan 2022
Thank you for the response.
I tried it but still given same error

Rik on 17 Jan 2022
You can resolve this error by making sure the dimensions agree.
If you think this answer is unhelpful; it is. If you want a more helpful answer you will have to provide more details.
An element-wise multiplication will work if isequal(size(A),size(B)). If non-matching dimensions are of length 1 and you are using R2016b or later, implicit expansion will cause expansion into an array:
A=rand(1,3);
B=rand(4,1);
size(A.*B)
ans = 1×2
4 3
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Olufemi Ologun on 17 Jan 2022
thank you
Rik on 17 Jan 2022
Is that the size, or the content? If it is the latter there should be no issue (except maybe what Max already wrote about the * instead of .*). If the former, how do you expect Matlab to multiply them? What should be the result of this?
[1 2;3 4].*[1 2 3;4 5 6;7 8 9]

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