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NAME
     spptrs - solve a system of linear equations A*X = B  with  a
     symmetric positive definite matrix A in packed storage using
     the Cholesky factorization A = U**T*U or A = L*L**T computed
     by SPPTRF

SYNOPSIS
     SUBROUTINE SPPTRS( UPLO, N, NRHS, AP, B, LDB, INFO )

     CHARACTER UPLO

     INTEGER INFO, LDB, N, NRHS

     REAL AP( * ), B( LDB, * )



     #include <sunperf.h>

     void spptrs(char uplo, int n, int nrhs,  float  *sap,  float
               *sb, int ldb, int *info) ;

PURPOSE
     SPPTRS solves a system of linear equations A*X =  B  with  a
     symmetric positive definite matrix A in packed storage using
     the Cholesky factorization A = U**T*U or A = L*L**T computed
     by SPPTRF.


ARGUMENTS
     UPLO      (input) CHARACTER*1
               = 'U':  Upper triangle of A is stored;
               = 'L':  Lower triangle of A is stored.

     N         (input) INTEGER
               The order of the matrix A.  N >= 0.

     NRHS      (input) INTEGER
               The number of right hand sides, i.e.,  the  number
               of columns of the matrix B.  NRHS >= 0.

     AP        (input) REAL array, dimension (N*(N+1)/2)
               The triangular factor U or  L  from  the  Cholesky
               factorization  A  =  U**T*U  or A = L*L**T, packed
               columnwise in a linear array.  The j-th column  of
               U  or  L is stored in the array AP as follows:  if
               UPLO  =  'U',  AP(i  +  (j-1)*j/2)  =  U(i,j)  for
               1<=i<=j;  if  UPLO = 'L', AP(i + (j-1)*(2n-j)/2) =
               L(i,j) for j<=i<=n.

     B         (input/output) REAL array, dimension (LDB,NRHS)
               On entry, the right hand side matrix B.  On  exit,
               the solution matrix X.

     LDB       (input) INTEGER
               The leading dimension of  the  array  B.   LDB  >=
               max(1,N).

     INFO      (output) INTEGER
               = 0:  successful exit
               < 0:  if INFO = -i, the i-th argument had an ille-
               gal value

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