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NAME
     spotri - compute the inverse of a  real  symmetric  positive
     definite  matrix  A  using  the  Cholesky  factorization A =
     U**T*U or A = L*L**T computed by SPOTRF

SYNOPSIS
     SUBROUTINE SPOTRI( UPLO, N, A, LDA, INFO )

     CHARACTER UPLO

     INTEGER INFO, LDA, N

     REAL A( LDA, * )



     #include <sunperf.h>

     void spotri(char uplo, int n, float *sa, int lda, int *info)
               ;

PURPOSE
     SPOTRI computes the inverse of  a  real  symmetric  positive
     definite  matrix  A  using  the  Cholesky  factorization A =
     U**T*U or A = L*L**T computed by SPOTRF.


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.

     A         (input/output) REAL array, dimension (LDA,N)
               On entry, the triangular factor U or  L  from  the
               Cholesky  factorization  A = U**T*U or A = L*L**T,
               as computed by SPOTRF.   On  exit,  the  upper  or
               lower  triangle  of  the (symmetric) inverse of A,
               overwriting the input factor U or L.

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

     INFO      (output) INTEGER
               = 0:  successful exit
               < 0:  if INFO = -i, the i-th argument had an ille-
               gal value
               > 0:  if INFO = i, the (i,i) element of the factor
               U  or  L  is  zero,  and  the inverse could not be
               computed.

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