[Numpy-discussion] How to efficiently multiply 2**10 x 2**10 hermitian matrices

qubax at gmx.at qubax at gmx.at
Thu Dec 30 14:07:14 EST 2010

I'll have to work with large hermitian matrices and calculate
traces, eigenvalues and perform several matric products. In order
to speed those up, i noticed that blas includes a function called
'zhemm' for efficient matrix products with at least one hermitian

is there a way to call that one directly for numpy arrays?

are there other, more efficient methods for multiplying that large
matrices that one of you might be aware of? especially with the
knowledge that they are symmetric/hermitian.

i'd appreciate any help in that regard.


ps: i tried to port the functionality of zhemm into cython, but this 
is still about a factor of 10 slower than directly using numpy.dot

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