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NAME
     sgbtrs - solve a system of linear equations  A * X = B or A'
     * X = B with a general band matrix A using the LU factoriza-
     tion computed by SGBTRF

SYNOPSIS
     SUBROUTINE SGBTRS( TRANS, N, KL, KU, NRHS, AB,  LDAB,  IPIV,
               B, LDB, INFO )

     CHARACTER TRANS

     INTEGER INFO, KL, KU, LDAB, LDB, N, NRHS

     INTEGER IPIV( * )

     REAL AB( LDAB, * ), B( LDB, * )



     #include <sunperf.h>

     void sgbtrs(char trans, int n, int kl,  int  ku,  int  nrhs,
               float  *sab, int ldab, int *ipivot, float *sb, int
               ldb, int *info) ;

PURPOSE
     SGBTRS solves a system of linear equations
        A * X = B  or  A' * X = B with a general  band  matrix  A
     using the LU factorization computed by SGBTRF.


ARGUMENTS
     TRANS     (input) CHARACTER*1
               Specifies the form of the system of equations.   =
               'N':  A * X = B  (No transpose)
               = 'T':  A'* X = B  (Transpose)
               = 'C':  A'* X = B  (Conjugate  transpose  =  Tran-
               spose)

     N         (input) INTEGER
               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.

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

     AB        (input) REAL array, dimension (LDAB,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.

     LDAB      (input) INTEGER
               The leading dimension of the array  AB.   LDAB  >=
               2*KL+KU+1.

     IPIV      (input) INTEGER array, dimension (N)
               The pivot indices; for 1 <= i <= N, row i  of  the
               matrix was interchanged with row IPIV(i).

     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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