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authordeaglanhalligan <deaglanhalligan@8a072113-8704-0410-8d35-dd094bca7971>2009-04-08 00:05:18 +0000
committerdeaglanhalligan <deaglanhalligan@8a072113-8704-0410-8d35-dd094bca7971>2009-04-08 00:05:18 +0000
commit47e45705b295f273c6c83f8b7f45a53cbce793d8 (patch)
tree03feea881aabfc40504b1cfdf35d1dd82d19b07d /SRC/sla_gbrcond.f
parent1d4ed33a5cfc65afcd46a0babb74979dfbed73f3 (diff)
Updated documentation for EPIR routines. Changed ERRS_{N,C} variable names. Other cosmetic changes.
Diffstat (limited to 'SRC/sla_gbrcond.f')
-rw-r--r--SRC/sla_gbrcond.f67
1 files changed, 61 insertions, 6 deletions
diff --git a/SRC/sla_gbrcond.f b/SRC/sla_gbrcond.f
index ee18d28c..77ffcdfd 100644
--- a/SRC/sla_gbrcond.f
+++ b/SRC/sla_gbrcond.f
@@ -37,9 +37,64 @@
* Arguments
* ==========
*
-* WORK real workspace of size 5*N.
+* TRANS (input) CHARACTER*1
+* Specifies the form of the system of equations:
+* = 'N': A * X = B (No transpose)
+* = 'T': A**T * X = B (Transpose)
+* = 'C': A**H * X = B (Conjugate Transpose = Transpose)
*
-* IWORK integer workspace of size N.
+* N (input) INTEGER
+* The number of linear equations, i.e., the order of the
+* matrix A. N >= 0.
+*
+* KL (input) INTEGER
+* The number of subdiagonals within the band of A. KL >= 0.
+*
+* KU (input) INTEGER
+* The number of superdiagonals within the band of A. KU >= 0.
+*
+* AB (input) REAL array, dimension (LDAB,N)
+* On entry, the matrix A in band storage, in rows 1 to KL+KU+1.
+* The j-th column of A is stored in the j-th column of the
+* array AB as follows:
+* AB(KU+1+i-j,j) = A(i,j) for max(1,j-KU)<=i<=min(N,j+kl)
+*
+* LDAB (input) INTEGER
+* The leading dimension of the array AB. LDAB >= KL+KU+1.
+*
+* AFB (input) REAL array, dimension (LDAFB,N)
+* Details of the LU factorization of the band matrix A, as
+* computed by SGBTRF. U is stored as an upper triangular
+* band matrix with KL+KU superdiagonals in rows 1 to KL+KU+1,
+* and the multipliers used during the factorization are stored
+* in rows KL+KU+2 to 2*KL+KU+1.
+*
+* LDAFB (input) INTEGER
+* The leading dimension of the array AFB. LDAFB >= 2*KL+KU+1.
+*
+* IPIV (input) INTEGER array, dimension (N)
+* The pivot indices from the factorization A = P*L*U
+* as computed by SGBTRF; row i of the matrix was interchanged
+* with row IPIV(i).
+*
+* CMODE (input) INTEGER
+* Determines op2(C) in the formula op(A) * op2(C) as follows:
+* CMODE = 1 op2(C) = C
+* CMODE = 0 op2(C) = I
+* CMODE = -1 op2(C) = inv(C)
+*
+* C (input) REAL array, dimension (N)
+* The vector C in the formula op(A) * op2(C).
+*
+* INFO (output) INTEGER
+* = 0: Successful exit.
+* i > 0: The ith argument is invalid.
+*
+* WORK (input) REAL array, dimension (5*N).
+* Workspace.
+*
+* IWORK (input) INTEGER array, dimension (N).
+* Workspace.
*
* =====================================================================
*
@@ -73,13 +128,13 @@
ELSE IF( N.LT.0 ) THEN
INFO = -2
ELSE IF( KL.LT.0 .OR. KL.GT.N-1 ) THEN
- INFO = -4
+ INFO = -3
ELSE IF( KU.LT.0 .OR. KU.GT.N-1 ) THEN
- INFO = -5
+ INFO = -4
ELSE IF( LDAB.LT.KL+KU+1 ) THEN
- INFO = -8
+ INFO = -6
ELSE IF( LDAFB.LT.2*KL+KU+1 ) THEN
- INFO = -10
+ INFO = -8
END IF
IF( INFO.NE.0 ) THEN
CALL XERBLA( 'SLA_GBRCOND', -INFO )