# tf.linalg.logm

Computes the matrix logarithm of one or more square matrices:

tf.linalg.logm(
input, name=None
)


$$log(exp(A)) = A$$

This op is only defined for complex matrices. If A is positive-definite and real, then casting to a complex matrix, taking the logarithm and casting back to a real matrix will give the correct result.

This function computes the matrix logarithm using the Schur-Parlett algorithm. Details of the algorithm can be found in Section 11.6.2 of: Nicholas J. Higham, Functions of Matrices: Theory and Computation, SIAM 2008. ISBN 978-0-898716-46-7.

The input is a tensor of shape [..., M, M] whose inner-most 2 dimensions form square matrices. The output is a tensor of the same shape as the input containing the exponential for all input submatrices [..., :, :].

#### Args:

• input: A Tensor. Must be one of the following types: complex64, complex128. Shape is [..., M, M].
• name: A name for the operation (optional).

#### Returns:

A Tensor. Has the same type as input.