.TH "slasy2.f" 3 "Sun May 26 2013" "Version 3.4.1" "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 \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 .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 November 2011 .RE .PP .PP Definition at line 174 of file slasy2\&.f\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.