# EigenValue function

**URL:** <https://community.freefem.org/t/eigenvalue-function/3180>\
**Category:** General Discussion\
**Created:** [April 30, 2024, 1:06pm UTC](https://community.freefem.org/t/eigenvalue-function/3180 "2024-04-30T13:06:21Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![maximefio](https://avatars.discourse-cdn.com/v4/letter/m/a6a055/32.png) [@maximefio](https://community.freefem.org/u/maximefio)\
**Post date:** [April 30, 2024, 1:06pm UTC](https://community.freefem.org/t/eigenvalue-function/3180/1 "2024-04-30T13:06:21Z")

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Hello,

I am currently trying to solve an eigenvalue problem with the function EigenValue of Freefem++ and when the code start to launch this function, I get such kind of error:

Assertion fail : ((!this-\>N() || !this-\>M()) || !Ax.x.N() || !this-\>N() || &Ax.x[0] != &this-\>operator)  
line :560, in file ./…/femlib/RNM.hpp

Is it a problem that already arrive or did I made something wrong in the code.

I thank you very much,

Maxime Fiore