XMM-Newton Science Analysis System


ssclib (ssclib-4.30) [xmmsas_20160201_1833-15.0.0]

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andRangesPair

This function takes as input two sequences of ranges and returns a sequence which contains all overlaps between the input ranges.

Points to note:

• The input range sequences must be well-formed (see section 9.5.1). The output is well-formed.

• The function returns a pointer argument. Deallocating this correctly is a little tricky, and I may eventually turn this (and all similar functions) into a subroutine. The function should NOT be called iteratively as in the following example:

  	andedRanges => andRangesPair(andedRanges, rangesB)
  

  The memory that the pointer andedRanges pointed to before the call now has no pointer to it, since at the moment the call is executed andedRanges is reassigned to the same memory that the function points to, which was newly assigned during the call. The initial memory pointed to by andedRanges therefore cannot now be deallocated. Better would be:

  	tempAndedRanges => andRangesPair(andedRanges, rangesB)
  	deallocate(andedRanges)
  	andedRanges => tempAndedRanges
  

  Then later, when appropriate, deallocate(andedRanges) for the final time.

%  function andRangesPair(rangesA, rangesB, doChecks) result(andedRanges)
  function andRangesPair(rangesA, rangesB) result(andedRanges)
    type(RangeT),  intent(in) :: rangesA(:), rangesB(:)
    type(RangeT),  pointer    :: andedRanges(:)
%    logical(bool), intent(in), optional :: doChecks
  end function andRangesPair