scipy.linalg.lapack.cpttrs

scipy.linalg.lapack.cpttrs(d, e, b, lower=0, overwrite_b=0) = <flapack function cpttrs>

Solve a positive definite tridiagonal system using the factorization from pttrf (LAPACK cpttrs).

Parameters:

dndarray

Diagonal of D from pttrf. Real for every flavor.

endarray

Off-diagonal of L from pttrf.

bndarray

Right-hand side(s) of shape (n, nrhs).

lowerint, optional

If nonzero, e is read as the subdiagonal of L; otherwise as the superdiagonal of U, which is its conjugate. Default is 0. Note pttrf writes the L form, so reusing its output here needs lower=1; the default silently solves a different system. The real flavors have no such argument, drawing no distinction between the two.

overwrite_bint, optional

If nonzero, b may be overwritten in place. Default is 0.

Returns:

xndarray

Solution of the system.

infoint

0 on success; if negative, the -info-th argument had an illegal value.