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

    The Swap the Elements of Two Vectors routine swaps n elements of
    the vector x with the vector y.

    Format

      BLAS1$VSSWAP  n ,x ,incx ,y ,incy

      BLAS1$VDSWAP  n ,x ,incx ,y ,incy

      BLAS1$VCSWAP  n ,x ,incx ,y ,incy

      BLAS1$VZSWAP  n ,x ,incx ,y ,incy

      Use BLAS1$VSSWAP for single-precision real operations.
      Use BLAS1$VDSWAP for double-precision real (D or G) operations.

      Use BLAS1$VCSWAP for single-precision complex operations.
      Use BLAS1$VZSWAP for double-precision complex (D or G)
      operations.

1 - Returns

    None.

2 - Arguments

 n

    OpenVMS usage:longword_signed
    type:         longword integer (signed)
    access:       read only
    mechanism:    by reference

    Number of elements in vector x to be swapped. The n argument is
    the address of a signed longword integer containing the number of
    elements to be swapped.

 x

    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, array reference

    Array containing the elements to be accessed. All elements of
    array x are accessed only if the increment argument of x, called
    incx, is 1. The x argument is the address of a floating-point or
    floating-point complex number that is this array. On entry, this
    argument is an array of length at least:

    1+(n-1)*|incx|

    where:

    n   =  number of vector elements specified in n
    incx=  increment argument for the array x specified in incx

    Specify the data type as follows:

    Routine            Data Type for x

    BLAS1$VSSWAP       F-floating real
    BLAS1$VDSWAP       D-floating or G-floating real
    BLAS1$VCSWAP       F-floating complex
    BLAS1$VZSWAP       D-floating or G-floating complex

    If n is less than or equal to 0, then x and y are unchanged. If
    any element of x shares a memory location with an element of y,
    the results are unpredictable.

    On exit, x is an array of length at least:

    1+(n-1)*|incx|

    where:

    n   =  number of vector elements specified in n
    incx=  increment argument for the array x specified in incx

    After the call to BLAS1$VxSWAP, n elements of the array specified
    by x are interchanged with n elements of the array specified by
    y.

 incx

    OpenVMS usage:longword_signed
    type:         longword integer (signed)
    access:       read only
    mechanism:    by reference

    Increment argument for the array x. The incx argument is the
    address of a signed longword integer containing the increment
    argument. If incx is greater than or equal to 0, then x is
    referenced forward in array x; that is, x[i] is referenced in:

    x(1+(i-1)*incx)

    where:

    x   =  array specified in x
    i   =  element of the vector x
    incx=  increment argument for the array x specified in incx

    If incx is less than 0, then x is referenced backward in array x;
    that is, x[i] is referenced in:

    x(1+(n-i)*|incx|)

    where:

    x   =  array specified in x
    n   =  number of vector elements specified in n
    i   =  element of the vector x
    incx=  increment argument for the array x specified in incx

 y

    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, array reference

    Array containing the elements to be accessed. All elements of
    array y are accessed only if the increment argument of y, called
    incy, is 1. The y argument is the address of a floating-point or
    floating-point complex number that is this array. On entry, this
    argument is an array of length at least:

    1+(n-1)*|incy|

    where:

    n   =  number of vector elements specified in n
    incy=  increment argument for the array y specified in incy

    Specify the data type as follows:

    Routine            Data Type for y

    BLAS1$VSSWAP       F-floating real
    BLAS1$VDSWAP       D-floating or G-floating real
    BLAS1$VCSWAP       F-floating complex
    BLAS1$VZSWAP       D-floating or G-floating complex

    If n is less than or equal to 0, then x and y are unchanged. If
    any element of x shares a memory location with an element of y,
    the results are unpredictable.

    On exit, y is an array of length at least:

    1+(n-1)*|incy|

    where:

    n   =  number of vector elements specified in n
    incy=  increment argument for the array y specified in incy

    After the call to BLAS1$VxSWAP, n elements of the array specified
    by x are interchanged with n elements of the array specified by
    y.

 incy

    OpenVMS usage:longword_signed
    type:         longword integer (signed)
    access:       read only
    mechanism:    by reference

    Increment argument for the array y. The incy argument is the
    address of a signed longword integer containing the increment
    argument. If incy is greater than or equal to 0, then y is
    referenced forward in array y; that is, y[i] is referenced in:

    y(1+(i-1)*incy)

    where:

    y   =  array specified in y
    i   =  element of the vector y
    incy=  increment argument for the array y specified in incy

    If incy is less than 0, then y is referenced backward in array y;
    that is, y[i] is referenced in:

    y(1+(n-i)*|incy|)

    where:

    y   =  array specified in y
    n   =  number of vector elements specified in n
    i   =  element of the vector y
    incy=  increment argument for the array y specified in incy