def check_dgbtrs(self):
"""Compare dgbtrs solutions for linear equation system A*x = b
with solutions of linalg.solve."""
lu_symm_band, ipiv, info = dgbtrf(self.bandmat_real, self.KL, self.KU)
y, info = dgbtrs(lu_symm_band, self.KL, self.KU, self.b, ipiv)
y_lin = linalg.solve(self.real_mat, self.b)
assert_array_almost_equal(y, y_lin)
def check_dgbtrf(self):
"""Compare dgbtrf LU factorisation with the LU factorisation result
of linalg.lu."""
M,N = shape(self.real_mat)
lu_symm_band, ipiv, info = dgbtrf(self.bandmat_real, self.KL, self.KU)
# extract matrix u from lu_symm_band
u = diag(lu_symm_band[2*self.KL,:])
for i in xrange(self.KL + self.KU):
u += diag(lu_symm_band[2*self.KL-1-i,i+1:N], i+1)
p_lin, l_lin, u_lin = lu(self.real_mat, permute_l=0)
assert_array_almost_equal(u, u_lin)
