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Re: Please explain this if you can: (short) [message #3212 is a reply to message #3211]

Mon, 05 December 1994 02:36

sjt
Messages: 72
Registered: November 1993

Member

Russ Welti (rwelti@chroma.mbt.washington.edu) wrote:
: Try this:

: IDL> a=bytarr(20)
: IDL> a(3)=244
: IDL> print,min(a)
: 0
: IDL> print,max(a)
: 244
: IDL> print,abs(max(a)-min(a))
: 12
: IDL> print,max(a)-min(a)
: 244

: What gives?
: \
: Russ Welti /-\
: (c-g)
: University of Washington \-/
: Dept. of Molecular Biotechnology M/S FJ-20 /
: Seattle, WA 98195 /-\
: (206) 685-3840 voice (a-t)
: (206) 685-7344 FAX \-/
: rwelti@u.washington.edu \

Evidently ABS isn't very bright! BYTE quantities are unsigned (try print,
min(a) - max(a)). But ABS for takes MSB set => negative and does a two's
complement on the argument.

--
+------------------------+---------------------------------- --+---------+
| James Tappin, | School of Physics & Space Research | O__ |
| sjt@star.sr.bham.ac.uk | University of Birmingham | -- \/` |
| "If all else fails--read the instructions!" | |
+----------------------------------------------------------- --+---------+

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[Message index]

		Re: Please explain this if you can: (short) By: pjclinch on Mon, 05 December 1994 05:46
		Re: Please explain this if you can: (short) By: greec on Mon, 05 December 1994 04:58
		Re: Please explain this if you can: (short) By: sjt on Mon, 05 December 1994 02:36

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