rotm(3) Library Functions Manual rotm(3) NAME rotm - rotm: apply modified (fast) plane rotation SYNOPSIS Functions subroutine drotm (n, dx, incx, dy, incy, dparam) DROTM subroutine srotm (n, sx, incx, sy, incy, sparam) SROTM Detailed Description Function Documentation subroutine drotm (integer n, double precision, dimension(*) dx, integer incx, double precision, dimension(*) dy, integer incy, double precision, dimension(5) dparam) DROTM Purpose: 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. Parameters N N is INTEGER number of elements in input vector(s) DX DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) INCX INCX is INTEGER storage spacing between elements of DX DY DY is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) INCY INCY is INTEGER storage spacing between elements of DY DPARAM DPARAM is DOUBLE PRECISION array, dimension (5) DPARAM(1)=DFLAG DPARAM(2)=DH11 DPARAM(3)=DH21 DPARAM(4)=DH12 DPARAM(5)=DH22 Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 95 of file drotm.f. subroutine srotm (integer n, real, dimension(*) sx, integer incx, real, dimension(*) sy, integer incy, real, dimension(5) sparam) SROTM Purpose: 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. Parameters N N is INTEGER number of elements in input vector(s) SX SX is REAL array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) INCX INCX is INTEGER storage spacing between elements of SX SY SY is REAL array, dimension ( 1 + ( N - 1 )*abs( INCY ) ) INCY INCY is INTEGER storage spacing between elements of SY SPARAM SPARAM is REAL array, dimension (5) SPARAM(1)=SFLAG SPARAM(2)=SH11 SPARAM(3)=SH21 SPARAM(4)=SH12 SPARAM(5)=SH22 Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 96 of file srotm.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 rotm(3)