VMS Help RTL Routines, MTH$, BLAS1$VxROTG  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The Generate the Elements for a Givens Plane Rotation routine
    constructs a Givens plane rotation that eliminates the second
    element of a two-element vector.

    Format

      BLAS1$VSROTG  a ,b ,c ,s

      BLAS1$VDROTG  a ,b ,c ,s

      BLAS1$VGROTG  a ,b ,c ,s

      BLAS1$VCROTG  a ,b ,c ,s

      BLAS1$VZROTG  a ,b ,c ,s

      BLAS1$VWROTG  a ,b ,c ,s

      Use BLAS1$VSROTG for single-precision real operations.
      Use BLAS1$VDROTG for double-precision real (D-floating)
      operations.
      Use BLAS1$VGROTG for double-precision real (G-floating)
      operations.

      Use BLAS1$VCROTG for single-precision complex operations.
      Use BLAS1$VZROTG for double-precision complex (D-floating)
      operations.
      Use BLAS1$VWROTG for double-precision complex (G-floating)
      operations.

1 - Returns

    None.

2 - Arguments

 a

    OpenVMS usage:floating_point or complex_number
    type:         F_floating, D_floating, G_floating real or
                  F_floating, D_floating, G_floating complex
    access:       modify
    mechanism:    by reference

    On entry, first element of the input vector. On exit, rotated
    element r. The a argument is the address of a floating-point or
    floating-point complex number that is this vector element.

    Specify the data type as follows:

    Routine            Data Type for a

    BLAS1$VSROTG       F-floating real
    BLAS1$VDROTG       D-floating real
    BLAS1$VGROTG       G-floating real
    BLAS1$VCROTG       F-floating complex
    BLAS1$VZROTG       D-floating complex
    BLAS1$VWROTG       G-floating complex

 b

    OpenVMS usage:floating_point or complex_number
    type:         F_floating, D_floating, G_floating real or
                  F_floating, D_floating, G_floating complex
    access:       modify
    mechanism:    by reference

    On entry, second element of the input vector. On exit from
    BLAS1$VSROTG, BLAS1$VDROTG, and BLAS1$VGROTG, reconstruction
    element z. The b argument is the address of a floating-point or
    floating-point complex number that is this vector element.

    Specify the data type as follows:

    Routine            Data Type for b

    BLAS1$VSROTG       F-floating real
    BLAS1$VDROTG       D-floating real
    BLAS1$VGROTG       G-floating real
    BLAS1$VCROTG       F-floating complex
    BLAS1$VZROTG       D-floating complex
    BLAS1$VWROTG       G-floating complex

 c

    OpenVMS usage:floating_point
    type:         F_floating, D_floating, or G_floating real
    access:       write only
    mechanism:    by reference

    First rotation element, which can be interpreted as the cosine
    of the angle of rotation. The c argument is the address of a
    floating-point or floating-point complex number that is this
    vector element.

    Specify the data type (which is always real) as follows:

    Routine            Data Type for c

    BLAS1$VSROTG and   F-floating real
    BLAS1$VCROTG
    BLAS1$VDROTG and   D-floating real
    BLAS1$VZROTG
    BLAS1$VGROTG and   G-floating real
    BLAS1$VWROTG

 s

    OpenVMS usage:floating_point or complex_number
    type:         F_floating, D_floating, G_floating real or
                  F_floating, D_floating, G_floating complex
    access:       write only
    mechanism:    by reference

    Second rotation element, which can be interpreted as the sine
    of the angle of rotation. The s argument is the address of a
    floating-point or floating-point complex number that is this
    vector element.

    Specify the data type as follows:

    Routine            Data Type for s

    BLAS1$VSROTG       F-floating real
    BLAS1$VDROTG       D-floating real
    BLAS1$VGROTG       G-floating real
    BLAS1$VCROTG       F-floating complex
    BLAS1$VZROTG       D-floating complex
    BLAS1$VWROTG       G-floating complex