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Arguments

D
(input) REAL array, shape with , where is the order of .
The diagonal of .

E
(input) REAL or COMPLEX array, shape with .
The subdiagonal of .

B
(input) REAL or COMPLEX array, shape with or shape with .
The matrix .

X
(output) REAL or COMPLEX array, shape with and , or shape with .
The solution matrix .

DF
Optional (input or output) REAL array, shape with the same size as D.
If FACT = 'F', then DF is an input argument that contains the diagonal of from the factorization of .
If 'N', then DF is an output argument that contains the diagonal of from the factorization of .

EF
Optional (input or output) REAL or COMPLEX array, shape with the same size as E.
If FACT = 'F', then EF is an input argument that contains the subdiagonal of from the factorization of .
If FACT = 'N', then EF is an output argument that contains the subdiagonal of from the factorization of .

FACT
Optional (input) CHARACTER(LEN=1).
Specifies whether the factored form of has been supplied on entry. Default value: 'N'.

FERR
Optional (output) REAL array of shape , with , or REAL scalar.
The estimated forward error bound for each solution vector (the column of the solution matrix ). If is the true solution corresponding to , is an estimated upper bound for the magnitude of the largest element in ( ) divided by the magnitude of the largest element in .

BERR
Optional (output) REAL array of shape , with , or REAL scalar.
The componentwise relative backward error of each solution vector (i.e., the smallest relative change in any element of or that makes an exact solution).

RCOND
Optional (output) REAL.
The estimate of the reciprocal condition number of the matrix . If is less than the machine precision, the matrix is singular to working precision. This condition is indicated by a return code of .

INFO
Optional (output) INTEGER If INFO is not present and an error occurs, then the program is terminated with an error message.
References:  and [17,9,20,21].

Subsections     Next: Example (from Program LA_PTSVX_EXAMPLE) Up: Symmetric/Hermitian Positive Definite Linear Previous: Description   Contents   Index
Susan Blackford 2001-08-19