`numpy:matvec`

source: /dev/numpy/build-install/usr/lib/python3.14/site-packages/numpy/__init__.py

Summary

Matrix-vector dot product of two arrays.

Extended Summary

Given a matrix (or stack of matrices) $A$ in x1 and a vector (or stack of vectors) $v$ in x2, the matrix-vector product is defined as:

A \cdot v = j = 0 \sum n - 1 A_{ij} v_{j}

where the sum is over the last dimensions in x1 and x2 (unless axes is specified). (For a matrix-vector product with the vector conjugated, use np.vecmat(x2, x1.mT).)

Parameters

x1, x2 : array_like: Input arrays, scalars not allowed.
out : ndarray, optional: A location into which the result is stored. If provided, it must have the broadcasted shape of x1 and x2 with the summation axis removed. If not provided or None, a freshly-allocated array is used.
**kwargs: For other keyword-only arguments, see the ufunc docs <ufuncs.kwargs>.

Returns

y : ndarray: The matrix-vector product of the inputs.

Raises

: ValueError

If the last dimensions of x1 and x2 are not the same size.

If a scalar value is passed in.

Examples

Rotate a set of vectors from Y to X along Z.

a = np.array([[0., 1., 0.],
              [-1., 0., 0.],
              [0., 0., 1.]])
v = np.array([[1., 0., 0.],
              [0., 1., 0.],
              [0., 0., 1.],
              [0., 6., 8.]])
np.matvec(a, v)

`numpy:matvec`

Summary

Extended Summary

Parameters

Returns

Raises

Examples

See also

Aliases

Referenced by

This package