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From: ZSYJKAA@WYOCDC1.BITNET (Jim Kirkpatrick 307 766-5303)
Newsgroups: comp.os.vms
Subject: COMPUTING PARITY
Message-ID: <880517130505.00000743.BAQK.83@WYOCDC1>
Date: 17 May 88 19:05:05 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
Lines: 11

Is there any quick method in VMS fortran to compute the parity of a
32-bit word?  Either a function that does exactly that, or one that
returns the number of "1" bits in the word?

By analogy, if you're familiar with Control Data Cybers, there's the
POP instruction (POPulation count) which returns the number of "1"
bits; checking the low bit of the count tells you if the word has even or
odd parity.  CDC Fortran has a corresponding intrinsic function.  The
best I can think of in VMS is to loop 32 times and use ISHFT and IAND.
      Jim Kirkpatrick     ZSYJKAA@WYOCDC1  (on BITNET)
      "help stamp out 5-page signature files"