scipy tutorial - Baustatik-Info-Server

cho_solve(clow, b)
Solve a previously factored symmetric system of equations.
The equation system is
A x = b, A = U^H U = L L^H
and A is real symmetric or complex Hermitian.
Parameters
clow : tuple (c, lower)
SciPy Reference Guide, Release 0.8.dev
Cholesky factor and a flag indicating whether it is lower triangular. The return value
from cho_factor can be used.
b : array
Right-hand side of the equation system
First input is a tuple (LorU, lower) which is the output to cho_factor. :
Second input is the right-hand side. :
Returns
x : array
Solution to the equation system
qr(a, overwrite_a=0, lwork=None, econ=None, mode=’qr’)
Compute QR decomposition of a matrix.
Calculate the decomposition :lm:‘A = Q R‘ where Q is unitary/orthogonal and R upper triangular.
Parameters
a : array, shape (M, N)
Matrix to be decomposed
overwrite_a : boolean
Whether data in a is overwritten (may improve performance)
lwork : integer
Work array size, lwork >= a.shape[1]. If None or -1, an optimal size is computed.
econ : boolean
Whether to compute the economy-size QR decomposition, making shapes of Q and
R (M, K) and (K, N) instead of (M,M) and (M,N). K=min(M,N). Default is False.
mode : {‘qr’, ‘r’}
Determines what information is to be returned: either both Q and R or only R.
Returns
(if mode == ‘qr’) :
Q : double or complex array, shape (M, M) or (M, K) for econ==True
(for any mode) :
R : double or complex array, shape (M, N) or (K, N) for econ==True
Size K = min(M, N)
Raises LinAlgError if decomposition fails :
3.7. Linear algebra (scipy.linalg) 239