.TH "csptri.f" 3 "Wed Oct 15 2014" "Version 3.4.2" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME csptri.f \- .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBcsptri\fP (UPLO, N, AP, IPIV, WORK, INFO)" .br .RI "\fI\fBCSPTRI\fP \fP" .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine csptri (characterUPLO, integerN, complex, dimension( * )AP, integer, dimension( * )IPIV, complex, dimension( * )WORK, integerINFO)" .PP \fBCSPTRI\fP .PP \fBPurpose: \fP .RS 4 .PP .nf CSPTRI computes the inverse of a complex symmetric indefinite matrix A in packed storage using the factorization A = U*D*U**T or A = L*D*L**T computed by CSPTRF. .fi .PP .RE .PP \fBParameters:\fP .RS 4 \fIUPLO\fP .PP .nf UPLO is CHARACTER*1 Specifies whether the details of the factorization are stored as an upper or lower triangular matrix. = 'U': Upper triangular, form is A = U*D*U**T; = 'L': Lower triangular, form is A = L*D*L**T. .fi .PP .br \fIN\fP .PP .nf N is INTEGER The order of the matrix A. N >= 0. .fi .PP .br \fIAP\fP .PP .nf AP is COMPLEX array, dimension (N*(N+1)/2) On entry, the block diagonal matrix D and the multipliers used to obtain the factor U or L as computed by CSPTRF, stored as a packed triangular matrix. On exit, if INFO = 0, the (symmetric) inverse of the original matrix, stored as a packed triangular matrix. The j-th column of inv(A) is stored in the array AP as follows: if UPLO = 'U', AP(i + (j-1)*j/2) = inv(A)(i,j) for 1<=i<=j; if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = inv(A)(i,j) for j<=i<=n. .fi .PP .br \fIIPIV\fP .PP .nf IPIV is INTEGER array, dimension (N) Details of the interchanges and the block structure of D as determined by CSPTRF. .fi .PP .br \fIWORK\fP .PP .nf WORK is COMPLEX array, dimension (N) .fi .PP .br \fIINFO\fP .PP .nf INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value > 0: if INFO = i, D(i,i) = 0; the matrix is singular and its inverse could not be computed. .fi .PP .RE .PP \fBAuthor:\fP .RS 4 Univ\&. of Tennessee .PP Univ\&. of California Berkeley .PP Univ\&. of Colorado Denver .PP NAG Ltd\&. .RE .PP \fBDate:\fP .RS 4 November 2011 .RE .PP .PP Definition at line 110 of file csptri\&.f\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.