.TH "rotm" 3 "Wed Feb 7 2024 11:30:40" "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
rotm \- rotm: apply modified (fast) plane rotation
.SH SYNOPSIS
.br
.PP
.SS "Functions"

.in +1c
.ti -1c
.RI "subroutine \fBdrotm\fP (n, dx, incx, dy, incy, dparam)"
.br
.RI "\fBDROTM\fP "
.ti -1c
.RI "subroutine \fBsrotm\fP (n, sx, incx, sy, incy, sparam)"
.br
.RI "\fBSROTM\fP "
.in -1c
.SH "Detailed Description"
.PP 

.SH "Function Documentation"
.PP 
.SS "subroutine drotm (integer n, double precision, dimension(*) dx, integer incx, double precision, dimension(*) dy, integer incy, double precision, dimension(5) dparam)"

.PP
\fBDROTM\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX

    (DX**T) , WHERE **T INDICATES TRANSPOSE\&. THE ELEMENTS OF DX ARE IN
    (DY**T)

    DX(LX+I*INCX), I = 0 TO N-1, WHERE LX = 1 IF INCX \&.GE\&. 0, ELSE
    LX = (-INCX)*N, AND SIMILARLY FOR SY USING LY AND INCY\&.
    WITH DPARAM(1)=DFLAG, H HAS ONE OF THE FOLLOWING FORMS\&.\&.

    DFLAG=-1\&.D0     DFLAG=0\&.D0        DFLAG=1\&.D0     DFLAG=-2\&.D0

      (DH11  DH12)    (1\&.D0  DH12)    (DH11  1\&.D0)    (1\&.D0  0\&.D0)
    H=(          )    (          )    (          )    (          )
      (DH21  DH22),   (DH21  1\&.D0),   (-1\&.D0 DH22),   (0\&.D0  1\&.D0)\&.
    SEE DROTMG FOR A DESCRIPTION OF DATA STORAGE IN DPARAM\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fIDX\fP 
.PP
.nf
          DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of DX
.fi
.PP
.br
\fIDY\fP 
.PP
.nf
          DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of DY
.fi
.PP
.br
\fIDPARAM\fP 
.PP
.nf
          DPARAM is DOUBLE PRECISION array, dimension (5)
     DPARAM(1)=DFLAG
     DPARAM(2)=DH11
     DPARAM(3)=DH21
     DPARAM(4)=DH12
     DPARAM(5)=DH22
.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

.SS "subroutine srotm (integer n, real, dimension(*) sx, integer incx, real, dimension(*) sy, integer incy, real, dimension(5) sparam)"

.PP
\fBSROTM\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
    APPLY THE MODIFIED GIVENS TRANSFORMATION, H, TO THE 2 BY N MATRIX

    (SX**T) , WHERE **T INDICATES TRANSPOSE\&. THE ELEMENTS OF SX ARE IN
    (SX**T)

    SX(LX+I*INCX), I = 0 TO N-1, WHERE LX = 1 IF INCX \&.GE\&. 0, ELSE
    LX = (-INCX)*N, AND SIMILARLY FOR SY USING USING LY AND INCY\&.
    WITH SPARAM(1)=SFLAG, H HAS ONE OF THE FOLLOWING FORMS\&.\&.

    SFLAG=-1\&.E0     SFLAG=0\&.E0        SFLAG=1\&.E0     SFLAG=-2\&.E0

      (SH11  SH12)    (1\&.E0  SH12)    (SH11  1\&.E0)    (1\&.E0  0\&.E0)
    H=(          )    (          )    (          )    (          )
      (SH21  SH22),   (SH21  1\&.E0),   (-1\&.E0 SH22),   (0\&.E0  1\&.E0)\&.
    SEE  SROTMG FOR A DESCRIPTION OF DATA STORAGE IN SPARAM\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
         number of elements in input vector(s)
.fi
.PP
.br
\fISX\fP 
.PP
.nf
          SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
.fi
.PP
.br
\fIINCX\fP 
.PP
.nf
          INCX is INTEGER
         storage spacing between elements of SX
.fi
.PP
.br
\fISY\fP 
.PP
.nf
          SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) )
.fi
.PP
.br
\fIINCY\fP 
.PP
.nf
          INCY is INTEGER
         storage spacing between elements of SY
.fi
.PP
.br
\fISPARAM\fP 
.PP
.nf
          SPARAM is REAL array, dimension (5)
     SPARAM(1)=SFLAG
     SPARAM(2)=SH11
     SPARAM(3)=SH21
     SPARAM(4)=SH12
     SPARAM(5)=SH22
.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

.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.