Can anyone explain what this means. "Warning: Matrix is ​​singular to working precision. "

Answer 1

[DGM]

For the future, post code using the formatting tools available to you. Do not post pictures of code. Nobody can run a picture of code.

The message means that some variable is singular or near-singular. In other words, it is not an invertible matrix.

If said matrix conceptually should be invertible, then you'll have to figure out why it's not.

[John D'Errico]

While someone might have tried to look at the code to see what the matrix Ek is composed of, there is no way to do so from a picture of code. So this answer says it all. +1

[Relly Syam]

thank you very much for your answers and suggestions