.TH "slasy2.f" 3 "Wed Oct 15 2014" "Version 3.4.2" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
slasy2.f \- 
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBslasy2\fP (LTRANL, LTRANR, ISGN, N1, N2, TL, LDTL, TR, LDTR, B, LDB, SCALE, X, LDX, XNORM, INFO)"
.br
.RI "\fI\fBSLASY2\fP solves the Sylvester matrix equation where the matrices are of order 1 or 2\&. \fP"
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine slasy2 (logicalLTRANL, logicalLTRANR, integerISGN, integerN1, integerN2, real, dimension( ldtl, * )TL, integerLDTL, real, dimension( ldtr, * )TR, integerLDTR, real, dimension( ldb, * )B, integerLDB, realSCALE, real, dimension( ldx, * )X, integerLDX, realXNORM, integerINFO)"

.PP
\fBSLASY2\fP solves the Sylvester matrix equation where the matrices are of order 1 or 2\&.  
.PP
\fBPurpose: \fP
.RS 4

.PP
.nf
 SLASY2 solves for the N1 by N2 matrix X, 1 <= N1,N2 <= 2, in

        op(TL)*X + ISGN*X*op(TR) = SCALE*B,

 where TL is N1 by N1, TR is N2 by N2, B is N1 by N2, and ISGN = 1 or
 -1.  op(T) = T or T**T, where T**T denotes the transpose of T.
.fi
.PP
 
.RE
.PP
\fBParameters:\fP
.RS 4
\fILTRANL\fP 
.PP
.nf
          LTRANL is LOGICAL
          On entry, LTRANL specifies the op(TL):
             = .FALSE., op(TL) = TL,
             = .TRUE., op(TL) = TL**T.
.fi
.PP
.br
\fILTRANR\fP 
.PP
.nf
          LTRANR is LOGICAL
          On entry, LTRANR specifies the op(TR):
            = .FALSE., op(TR) = TR,
            = .TRUE., op(TR) = TR**T.
.fi
.PP
.br
\fIISGN\fP 
.PP
.nf
          ISGN is INTEGER
          On entry, ISGN specifies the sign of the equation
          as described before. ISGN may only be 1 or -1.
.fi
.PP
.br
\fIN1\fP 
.PP
.nf
          N1 is INTEGER
          On entry, N1 specifies the order of matrix TL.
          N1 may only be 0, 1 or 2.
.fi
.PP
.br
\fIN2\fP 
.PP
.nf
          N2 is INTEGER
          On entry, N2 specifies the order of matrix TR.
          N2 may only be 0, 1 or 2.
.fi
.PP
.br
\fITL\fP 
.PP
.nf
          TL is REAL array, dimension (LDTL,2)
          On entry, TL contains an N1 by N1 matrix.
.fi
.PP
.br
\fILDTL\fP 
.PP
.nf
          LDTL is INTEGER
          The leading dimension of the matrix TL. LDTL >= max(1,N1).
.fi
.PP
.br
\fITR\fP 
.PP
.nf
          TR is REAL array, dimension (LDTR,2)
          On entry, TR contains an N2 by N2 matrix.
.fi
.PP
.br
\fILDTR\fP 
.PP
.nf
          LDTR is INTEGER
          The leading dimension of the matrix TR. LDTR >= max(1,N2).
.fi
.PP
.br
\fIB\fP 
.PP
.nf
          B is REAL array, dimension (LDB,2)
          On entry, the N1 by N2 matrix B contains the right-hand
          side of the equation.
.fi
.PP
.br
\fILDB\fP 
.PP
.nf
          LDB is INTEGER
          The leading dimension of the matrix B. LDB >= max(1,N1).
.fi
.PP
.br
\fISCALE\fP 
.PP
.nf
          SCALE is REAL
          On exit, SCALE contains the scale factor. SCALE is chosen
          less than or equal to 1 to prevent the solution overflowing.
.fi
.PP
.br
\fIX\fP 
.PP
.nf
          X is REAL array, dimension (LDX,2)
          On exit, X contains the N1 by N2 solution.
.fi
.PP
.br
\fILDX\fP 
.PP
.nf
          LDX is INTEGER
          The leading dimension of the matrix X. LDX >= max(1,N1).
.fi
.PP
.br
\fIXNORM\fP 
.PP
.nf
          XNORM is REAL
          On exit, XNORM is the infinity-norm of the solution.
.fi
.PP
.br
\fIINFO\fP 
.PP
.nf
          INFO is INTEGER
          On exit, INFO is set to
             0: successful exit.
             1: TL and TR have too close eigenvalues, so TL or
                TR is perturbed to get a nonsingular equation.
          NOTE: In the interests of speed, this routine does not
                check the inputs for errors.
.fi
.PP
 
.RE
.PP
\fBAuthor:\fP
.RS 4
Univ\&. of Tennessee 
.PP
Univ\&. of California Berkeley 
.PP
Univ\&. of Colorado Denver 
.PP
NAG Ltd\&. 
.RE
.PP
\fBDate:\fP
.RS 4
September 2012 
.RE
.PP

.PP
Definition at line 174 of file slasy2\&.f\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.