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      SUBROUTINE CPOTRIF( UPLO, N, A, LDA, INFO )
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*
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*  -- LAPACK routine (version 3.1) --
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*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
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*     November 2006
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*
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*     .. Scalar Arguments ..
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      CHARACTER          UPLO
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      INTEGER            INFO, LDA, N
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*     ..
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*     .. Array Arguments ..
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      COMPLEX            A( LDA, * )
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*     ..
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*
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*  Purpose
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*  =======
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*
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*  CPOTRI computes the inverse of a complex Hermitian positive definite
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*  matrix A using the Cholesky factorization A = U**H*U or A = L*L**H
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*  computed by CPOTRF.
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*
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*  Arguments
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*  =========
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*
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*  UPLO    (input) CHARACTER*1
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*          = 'U':  Upper triangle of A is stored;
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*          = 'L':  Lower triangle of A is stored.
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*
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*  N       (input) INTEGER
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*          The order of the matrix A.  N >= 0.
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*
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*  A       (input/output) COMPLEX array, dimension (LDA,N)
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*          On entry, the triangular factor U or L from the Cholesky
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*          factorization A = U**H*U or A = L*L**H, as computed by
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*          CPOTRF.
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*          On exit, the upper or lower triangle of the (Hermitian)
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*          inverse of A, overwriting the input factor U or L.
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*
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*  LDA     (input) INTEGER
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*          The leading dimension of the array A.  LDA >= max(1,N).
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*
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*  INFO    (output) INTEGER
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*          = 0:  successful exit
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*          < 0:  if INFO = -i, the i-th argument had an illegal value
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*          > 0:  if INFO = i, the (i,i) element of the factor U or L is
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*                zero, and the inverse could not be computed.
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*
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*  =====================================================================
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*
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*     .. External Functions ..
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      LOGICAL            LSAME
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      EXTERNAL           LSAME
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*     ..
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*     .. External Subroutines ..
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      EXTERNAL           CLAUUM, CTRTRI, XERBLA
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*     ..
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*     .. Intrinsic Functions ..
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      INTRINSIC          MAX
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*     ..
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*     .. Executable Statements ..
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*
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*     Test the input parameters.
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*
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      INFO = 0
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      IF( .NOT.LSAME( UPLO, 'U' ) .AND. .NOT.LSAME( UPLO, 'L' ) ) THEN
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         INFO = -1
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      ELSE IF( N.LT.0 ) THEN
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         INFO = -2
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      ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
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         INFO = -4
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      END IF
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      IF( INFO.NE.0 ) THEN
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         CALL XERBLA( 'CPOTRI', -INFO )
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         RETURN
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      END IF
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*
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*     Quick return if possible
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*
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      IF( N.EQ.0 )
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     $   RETURN
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*
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*     Invert the triangular Cholesky factor U or L.
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*
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      CALL CTRTRI( UPLO, 'Non-unit', N, A, LDA, INFO )
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      IF( INFO.GT.0 )
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     $   RETURN
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*
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*     Form inv(U)*inv(U)' or inv(L)'*inv(L).
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*
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      CALL CLAUUM( UPLO, N, A, LDA, INFO )
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*
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      RETURN
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*
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*     End of CPOTRI
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*
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      END