bundles / numpy 2.4.3 / numpy / vecmat
ufunc
numpy:vecmat
source: /numpy/__init__.py
Summary
Vector-matrix dot product of two arrays.
Extended Summary
Given a vector (or stack of vector) in x1 and a matrix (or stack of matrices) in x2, the vector-matrix product is defined as:
where the sum is over the last dimension of x1 and the one-but-last dimensions in x2 (unless axes is specified) and where denotes the complex conjugate if is complex and the identity otherwise. (For a non-conjugated vector-matrix product, use np.matvec(x2.mT, x1).)
Parameters
x1, x2: array_likeInput arrays, scalars not allowed.
out: ndarray, optionalA location into which the result is stored. If provided, it must have the broadcasted shape of
x1andx2with the summation axis removed. If not provided or None, a freshly-allocated array is used.**kwargsFor other keyword-only arguments, see the
ufunc docs <ufuncs.kwargs>.
Returns
y: ndarrayThe vector-matrix product of the inputs.
Raises
: ValueErrorIf the last dimensions of
x1and the one-but-last dimension ofx2are not the same size.If a scalar value is passed in.
Examples
Project a vector along X and Y.v = np.array([0., 4., 2.]) a = np.array([[1., 0., 0.], [0., 1., 0.], [0., 0., 0.]])✓
np.vecmat(v, a)
✗See also
- einsum
Einstein summation convention.
- matmul
Matrix-matrix product.
- matvec
Matrix-vector product.
- vecdot
Vector-vector product.
Aliases
-
numpy.vecmat