.TH "dlags2.f" 3 "Wed Oct 15 2014" "Version 3.4.2" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
dlags2.f \- 
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBdlags2\fP (UPPER, A1, A2, A3, B1, B2, B3, CSU, SNU, CSV, SNV, CSQ, SNQ)"
.br
.RI "\fI\fBDLAGS2\fP computes 2-by-2 orthogonal matrices U, V, and Q, and applies them to matrices A and B such that the rows of the transformed A and B are parallel\&. \fP"
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dlags2 (logicalUPPER, double precisionA1, double precisionA2, double precisionA3, double precisionB1, double precisionB2, double precisionB3, double precisionCSU, double precisionSNU, double precisionCSV, double precisionSNV, double precisionCSQ, double precisionSNQ)"

.PP
\fBDLAGS2\fP computes 2-by-2 orthogonal matrices U, V, and Q, and applies them to matrices A and B such that the rows of the transformed A and B are parallel\&.  
.PP
\fBPurpose: \fP
.RS 4

.PP
.nf
 DLAGS2 computes 2-by-2 orthogonal matrices U, V and Q, such
 that if ( UPPER ) then

           U**T *A*Q = U**T *( A1 A2 )*Q = ( x  0  )
                             ( 0  A3 )     ( x  x  )
 and
           V**T*B*Q = V**T *( B1 B2 )*Q = ( x  0  )
                            ( 0  B3 )     ( x  x  )

 or if ( .NOT.UPPER ) then

           U**T *A*Q = U**T *( A1 0  )*Q = ( x  x  )
                             ( A2 A3 )     ( 0  x  )
 and
           V**T*B*Q = V**T*( B1 0  )*Q = ( x  x  )
                           ( B2 B3 )     ( 0  x  )

 The rows of the transformed A and B are parallel, where

   U = (  CSU  SNU ), V = (  CSV SNV ), Q = (  CSQ   SNQ )
       ( -SNU  CSU )      ( -SNV CSV )      ( -SNQ   CSQ )

 Z**T denotes the transpose of Z.
.fi
.PP
 
.RE
.PP
\fBParameters:\fP
.RS 4
\fIUPPER\fP 
.PP
.nf
          UPPER is LOGICAL
          = .TRUE.: the input matrices A and B are upper triangular.
          = .FALSE.: the input matrices A and B are lower triangular.
.fi
.PP
.br
\fIA1\fP 
.PP
.nf
          A1 is DOUBLE PRECISION
.fi
.PP
.br
\fIA2\fP 
.PP
.nf
          A2 is DOUBLE PRECISION
.fi
.PP
.br
\fIA3\fP 
.PP
.nf
          A3 is DOUBLE PRECISION
          On entry, A1, A2 and A3 are elements of the input 2-by-2
          upper (lower) triangular matrix A.
.fi
.PP
.br
\fIB1\fP 
.PP
.nf
          B1 is DOUBLE PRECISION
.fi
.PP
.br
\fIB2\fP 
.PP
.nf
          B2 is DOUBLE PRECISION
.fi
.PP
.br
\fIB3\fP 
.PP
.nf
          B3 is DOUBLE PRECISION
          On entry, B1, B2 and B3 are elements of the input 2-by-2
          upper (lower) triangular matrix B.
.fi
.PP
.br
\fICSU\fP 
.PP
.nf
          CSU is DOUBLE PRECISION
.fi
.PP
.br
\fISNU\fP 
.PP
.nf
          SNU is DOUBLE PRECISION
          The desired orthogonal matrix U.
.fi
.PP
.br
\fICSV\fP 
.PP
.nf
          CSV is DOUBLE PRECISION
.fi
.PP
.br
\fISNV\fP 
.PP
.nf
          SNV is DOUBLE PRECISION
          The desired orthogonal matrix V.
.fi
.PP
.br
\fICSQ\fP 
.PP
.nf
          CSQ is DOUBLE PRECISION
.fi
.PP
.br
\fISNQ\fP 
.PP
.nf
          SNQ is DOUBLE PRECISION
          The desired orthogonal matrix Q.
.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 152 of file dlags2\&.f\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.