HELP ARRAY_ADJOIN                               David Young
                                                August 2002

___LIB * ____________ARRAY_ADJOIN provides a procedure to adjoin - that is, put next to
each other - two 2-D arrays.

array_adjoin(____arr1, ____reg1, ____arr2, ____reg2, ____side, ____arr3) -> ____arr3
        ____arr1 is the first input array. It must be 2-D. Arrays of packed
        byte or float data (as created by *newbytearray and
        *newsfloatarray) are handled most efficiently.

        ____reg1 gives the region of ____arr1 from which to take data. It may be
        a *boundslist type list or <false> to mean the whole of the
        array.

        ____arr2 and ____reg2 specify the second array and region in the same
        way.

        Below, ____reg1 and ____reg2 refer to the regions of the arrays from
        which data are to be taken, which may be the whole array.

        ____side specifies which side of ____reg1 to adjoin ____reg2 to. It may be
        one of the words "top", "right", "bottom", "left", or "t", "r",
        "b", "l". These refer to the sides of the region when the array
        is displayed conventionally as an image on the screen, using
        e.g. *rci_show. ____side may also be an integer, in which case (____side
        mod 4) = 0,1,2,3 means t,r,b,l respectively.

        ____arr3 may be <false>, in which case a new output array is created
        and returned, or it may be an array in which the data are to be
        placed, in which case it is returned as the result. On exit,
        ____arr3(_x, _y) = ____arr1(_x, _y) for all (_x, _y) within ____reg1;
        ____arr3(_x+__xs, _y+__ys) = ___arr2(_x, _y) for all (_x, _y) within ____reg2, where
        __xs and __ys are the shifts necessary to move the data from ____reg2 to
        lie beside the data from ____reg1.

        If ____arr3 is an array on entry, its boundslist must contain the
        region in which data are to be stored.


--- ____________________________$popvision/help/array_adjoin
--- _________Copyright __________University __of ______Sussex _____2002. ___All ______rights _________reserved.