>From my Finite Element code I generate a global stiffness matrix K.

However, I can not use the cholesky factorization on it because of

ERROR: ArgumentError: sparse matrix is not symmetric/Hermitian
 in cholfact at sparse/cholmod.jl:916
 in cholfact at sparse/cholmod.jl:991

However, I am pretty sure it is symmetric and positive definite.

For example:
julia> issym(K)
false

julia> maximum(abs(K - K'))
4.440892098500626e-16

Matlab for example has no problem running chol on it when I copy + paste it.

This works (of course):
julia> cholfact((K + K')/2)

Are the tolerances for the Hermitian check set too small or is there maybe 
a specific symmetric sparse type I should use when I know my matrix will be 
symm + pos def?

Best regards,
Kristoffer Carlsson

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