Flaw found in histogram on Red Hat Linux

[grunes(at)yahoo.com]

Under some conditions, the histogram function causes IDL
to crash with a corrupt array descriptor.  I was unable to
duplicate the error on other platforms with older versions
of IDL and PV-WAVE.

I would be curious to know if anyone could test this on
a version of PV-WAVE for Linux, or on recent versions of
IDL on other platforms.

---------Begin Included Program----------

; Attempt by mitch grunes to make IDL histogram fail
;  with a corrupt array descriptor.
; The failure is noted on Red Hat Linux 6.0 or Mandrake
; Linux 7.1 with IDL 5.2 or 5.3.
;=========Subroutine==========
  pro test1,a
  bot=min(a)
  top=max(a)
  bin=(top-bot)/4000
  hist=histogram(a,min=bot,max=top,bin=bin)
  end
;=========Main Program=========
  for i=0,1000 do begin
    print,i
    a=randomu(seed,1540,704)
    test1,a
  endfor
  end

----------End Included Program----------

I was able to get around the error by bumping top up a
little, but that seems unsatisfactory.

(I have noted in the past that histogram returned
incorrect values [total of histogram does not equal
# of elements] when handling arrays on the order
of 100,000,000 elements, as though they maybe used
floating point counters instead of integral.
I think it may have been implemented a bit sloppily
in general.)



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