.TH "SRC/sspev.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME SRC/sspev.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBsspev\fP (jobz, uplo, n, ap, w, z, ldz, work, info)" .br .RI "\fB SSPEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for OTHER matrices\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine sspev (character jobz, character uplo, integer n, real, dimension( * ) ap, real, dimension( * ) w, real, dimension( ldz, * ) z, integer ldz, real, dimension( * ) work, integer info)" .PP \fB SSPEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for OTHER matrices\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> SSPEV computes all the eigenvalues and, optionally, eigenvectors of a !> real symmetric matrix A in packed storage\&. !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fIJOBZ\fP .PP .nf !> JOBZ is CHARACTER*1 !> = 'N': Compute eigenvalues only; !> = 'V': Compute eigenvalues and eigenvectors\&. !> .fi .PP .br \fIUPLO\fP .PP .nf !> UPLO is CHARACTER*1 !> = 'U': Upper triangle of A is stored; !> = 'L': Lower triangle of A is stored\&. !> .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 REAL array, dimension (N*(N+1)/2) !> On entry, the upper or lower triangle of the symmetric matrix !> A, packed columnwise in a linear array\&. The j-th column of A !> is stored in the array AP as follows: !> if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j; !> if UPLO = 'L', AP(i + (j-1)*(2*n-j)/2) = A(i,j) for j<=i<=n\&. !> !> On exit, AP is overwritten by values generated during the !> reduction to tridiagonal form\&. If UPLO = 'U', the diagonal !> and first superdiagonal of the tridiagonal matrix T overwrite !> the corresponding elements of A, and if UPLO = 'L', the !> diagonal and first subdiagonal of T overwrite the !> corresponding elements of A\&. !> .fi .PP .br \fIW\fP .PP .nf !> W is REAL array, dimension (N) !> If INFO = 0, the eigenvalues in ascending order\&. !> .fi .PP .br \fIZ\fP .PP .nf !> Z is REAL array, dimension (LDZ, N) !> If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal !> eigenvectors of the matrix A, with the i-th column of Z !> holding the eigenvector associated with W(i)\&. !> If JOBZ = 'N', then Z is not referenced\&. !> .fi .PP .br \fILDZ\fP .PP .nf !> LDZ is INTEGER !> The leading dimension of the array Z\&. LDZ >= 1, and if !> JOBZ = 'V', LDZ >= max(1,N)\&. !> .fi .PP .br \fIWORK\fP .PP .nf !> WORK is REAL array, dimension (3*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, the algorithm failed to converge; i !> off-diagonal elements of an intermediate tridiagonal !> form did not converge to zero\&. !> .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 .PP Definition at line \fB129\fP of file \fBsspev\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.