`scipy.linalg._fblas:cgemv`

Signature

def cgemv(alpha, a, x, beta = 0.0, y = None, offx = 0, incx = 1, offy = 0, incy = 1, trans = 0, overwrite_y = 0)

Compute the matrix-vector product y = alpha*op(a)@x + beta*y (BLAS cgemv).

alpha : complex: Scalar multiplier for the product.
a : ndarray: Input matrix.
x : ndarray: Input vector.
beta : complex, optional: Scalar multiplier for y. Default is 0.
y : ndarray, optional: Input/output vector; if omitted a new zero vector is allocated. Default is None.
offx : int, optional: Index of the first element of x to use. Default is 0.
incx : int, optional: Stride between successive elements of x. Default is 1.
offy : int, optional: Index of the first element of y to use. Default is 0.
incy : int, optional: Stride between successive elements of y. Default is 1.
trans : int, optional: Operation on the matrix: 0 none, 1 transpose, 2 conjugate transpose. Default is 0.
overwrite_y : int, optional: If nonzero, y may be overwritten in place. Default is 0.

y : ndarray: The vector alpha*op(a)@x + beta*y, where op(a) is a, a.T, or a.conj().T according to trans.