COMPUTE BTEST

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COMPUTE BTEST

            [SIC\]COMPUTE OutVar BTEST InVar [Ibit]

        Bit-test  one  or  several  bit values of the input variable, and return
        true for each bit equal to 1.

        The optional integer argument Ibit indicate which bit should be  tested.
        The default is to check all the bits.

        If  all  the bits of (a single element of) InVar are tested, OutVar must
        be an array with its first dimension equal to this number of bits,  e.g.
        32  for  INTEGERs, 64 for DOUBLEs, etc. InVar may be a multi-dimensional
        array, in which case OutVar must have the same extra-dimensions.

        In details, this tool is an overlay to the BTEST Fortran  function  (ex-
        cept  that bit numbering starts at 1 here). Note that this hides the ma-
        chine dependencies (IEEE, EEEI, etc) by using a unique integer model re-
        gardless  of  its physical layout. For more information, please refer to
        the Fortran documentation.

        Examples:

        SIC> define integer i
        SIC> let i 2
        SIC> define logical one
        SIC> compute one btest i 1  ! First bit value
        SIC> exa one
        ONE             = F                          ! Logical GLOBAL

        SIC> define logical all[32]
        SIC> compute all btest i  ! All bit values
        SIC> exa all
        ALL             is a logical Array     of dimensions  32
         F T F F F F F F F F F F F F F F F F F F F F F F
         F F F F F F F F

        SIC> define integer i2[3]
        SIC> let i2 1 2 3
        SIC> define logical one2[3]
        SIC> compute one2 btest i2 2  ! Second bit values of the 3 elements
        SIC> exa one2
        ONE2            is a logical Array     of dimensions  3
         F T T

        SIC> define logical all2[32,3]
        SIC> compute all2 btest i2  ! All bit values of all elements
        SIC> exa all2[1] all2[2] all2[3]
        ALL2[1]         is a logical Sub-Array of dimensions  32
         T F F F F F F F F F F F F F F F F F F F F F F F
         F F F F F F F F
        ALL2[2]         is a logical Sub-Array of dimensions  32
         F T F F F F F F F F F F F F F F F F F F F F F F
         F F F F F F F F
        ALL2[3]         is a logical Sub-Array of dimensions  32
         T T F F F F F F F F F F F F F F F F F F F F F F
         F F F F F F F F