Arrays have incompatible sizes for this operation.

sigma_r = 1/2.*'sigma_0'.*(1-('ksi'.^2))-(1/2.*'sigma_0'.*(1+(3.*('ksi'.^4))-(4.*('ksi'.^4)))).*cos(2.*'theta')

[Torsten]

What does the ' ' used for variable names mean ?

[Rik]

Editing away your question is very rude. Someone spent time reading your question, understanding your issue, figuring out the solution, and writing an answer. Now you repay that kindness by ensuring that the next person with a similar question can't benefit from this answer.

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Voss]

It seems unlikely that you mean to be doing numerical operations on character vetors like that

1/2.*'sigma_0'

ans = 1x7

57.5000 52.5000 51.5000 54.5000 48.5000 47.5000 24.0000

Maybe you meant to define those variables

sigma_0 = 4;

1/2.*sigma_0

ans = 2

[ueqweoıqwueoq]

Thanks

[Voss]

You're welcome!