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bundles / scipy latest / scipy / linalg / _expm_frechet / expm_cond

function

scipy.linalg._expm_frechet:expm_cond

source: /scipy/linalg/_expm_frechet.py :357

Signature

def   expm_cond ( A check_finite = True )

Summary

Relative condition number of the matrix exponential in the Frobenius norm.

Extended Summary

The documentation is written assuming array arguments are of specified "core" shapes. However, array argument(s) of this function may have additional "batch" dimensions prepended to the core shape. In this case, the array is treated as a batch of lower-dimensional slices; see linalg_batch for details. Note that calls with zero-size batches are unsupported and will raise a ValueError.

Parameters

A : 2-D array_like

Square input matrix with shape (N, N).

check_finite : bool, optional

Whether to check that the input matrix contains only finite numbers. Disabling may give a performance gain, but may result in problems (crashes, non-termination) if the inputs do contain infinities or NaNs.

Returns

kappa : float

The relative condition number of the matrix exponential in the Frobenius norm

Notes

A faster estimate for the condition number in the 1-norm has been published but is not yet implemented in SciPy.

Examples

import numpy as np
from scipy.linalg import expm_cond
A = np.array([[-0.3, 0.2, 0.6], [0.6, 0.3, -0.1], [-0.7, 1.2, 0.9]])
k = expm_cond(A)
k

See also

expm

Compute the exponential of a matrix.

expm_frechet

Compute the Frechet derivative of the matrix exponential.

Aliases

  • scipy.linalg.expm_cond

Referenced by

This package