Updated documentation for EPIR routines. Changed ERRS_{N,C} variable names. Other cosmetic changes.

1 files changed, 28 insertions, 1 deletions

diff --git a/SRC/sla_porpvgrw.f b/SRC/sla_porpvgrw.f
index 05b89df0..aba969a0 100644
--- a/SRC/sla_porpvgrw.f
+++ b/SRC/sla_porpvgrw.f
@@ -21,11 +21,38 @@
 *  Purpose
 *  =======
 * 
-*  SLA_PORPVGRW computes ... .
+*  SLA_PORPVGRW computes the reciprocal pivot growth factor
+*  norm(A)/norm(U). The "max absolute element" norm is used. If this is
+*  much less than 1, the stability of the LU factorization of the
+*  (equilibrated) matrix A could be poor. This also means that the
+*  solution X, estimated condition numbers, and error bounds could be
+*  unreliable.
 *
 *  Arguments
 *  =========
 *
+*     UPLO    (input) CHARACTER*1
+*       = 'U':  Upper triangle of A is stored;
+*       = 'L':  Lower triangle of A is stored.
+*
+*     NCOLS   (input) INTEGER
+*     The number of columns of the matrix A. NCOLS >= 0.
+*
+*     A       (input) REAL array, dimension (LDA,N)
+*     On entry, the N-by-N matrix A.
+*
+*     LDA     (input) INTEGER
+*     The leading dimension of the array A.  LDA >= max(1,N).
+*
+*     AF      (input) REAL array, dimension (LDAF,N)
+*     The triangular factor U or L from the Cholesky factorization
+*     A = U**T*U or A = L*L**T, as computed by SPOTRF.
+*
+*     LDAF    (input) INTEGER
+*     The leading dimension of the array AF.  LDAF >= max(1,N).
+*
+*     WORK    (input) REAL array, dimension (2*N)
+*
 *  =====================================================================
 *
 *     .. Local Scalars ..