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From: sburke@jarthur.Claremont.EDU (Scott Burke)
Newsgroups: comp.sys.handhelds
Subject: Re: Questions Regarding Lists & The Solver
Message-ID: <10888@jarthur.Claremont.EDU>
Date: 19 Feb 91 22:20:16 GMT
References: <1991Feb19.080133.24204@bronze.ucs.indiana.edu> <20339@shlump.nac.dec.com>
Organization: Harvey Mudd College, Claremont, CA 91711
Lines: 23

Jim Donnelly's Toolkit contains a few words that are useful when it comes
to extracting atoms from lists.  Atoms?  You must be a LISPer.  Anyways...

DIFF takes { A B C } { B } and returns { A C }
     takes { 1 2 3 4 } { 5 6 } and returns { 1 2 3 4 }
     takes { 1 2 3 4 } { 3 4 5 } and returns { 1 2 }

SDIFF takes { 1 2 3 4 } { 5 6 } and returns { 1 2 3 4 5 6 }
      takes { 1 2 3 4 } { 3 4 5 } and returns { 1 2 5 }

(SDIFF is the set symmetric difference; DIFF merely the set difference)

Other useful set commands in the Toolkit are:

  ADJOIN:  Adds an object to a list if it is unique
  INTERSECT:  Returns the set intersection between two lists
  \->SET:  Removes duplicate objects from a list
  UNION:  Returns the set union of two lists

The Toolkit is highly recommended by me.  It is available from EduCalc.

Scott.
sburke@jarthur.claremont.edu