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Nonatomic expression error encountered with Intersection

• To: mathgroup at smc.vnet.net
• Subject: [mg53597] Nonatomic expression error encountered with Intersection
• From: Todd Allen <genesplicer28 at yahoo.com>
• Date: Wed, 19 Jan 2005 02:00:24 -0500 (EST)
• Sender: owner-wri-mathgroup at wolfram.com

Hi everyone,

    I was hoping the usergroup might have some
thoughts on a peculiar error message I have been
receiving from Mathematica V 5.1(win XP).

    I have a set of nested loops where I try to
compare the elements of two matrices using
Intersection, and if there is indeed an intersection,
make a change to one of the matrices.  The code
generates an error message: Intersection::normal:
"Nonatomic expression expected at position 1.......

I believe the Head of the two lists I am comparing are
in fact lists, however perhaps I am missing something
as to how mathemamatica parses the input.

Below is the basic code:

temp=
{{CEST-01-A-01,CEST-17-A-06},{CEST-01-A-02,CEST-01-A-06,CEST-02-C-06,
   
CEST-03-B-03,CEST-03-G-07,CEST-05-C-11,CEST-06-A-09,CEST-08-B-07,
   
CEST-09-A-02,CEST-12-A-06,CEST-12-G-11,CEST-16-C-02,CEST-16-H-04,
   
CEST-17-A-04,CEST-18-D-05,CEST-19-C-01,CEST-19-D-04,CEST-19-G-01,
   
CEST-20-C-09,CEST-20-G-08,CEST-22-D-07,CEST-22-D-11,CEST-23-C-09,
   
CEST-26-G-08,CEST-27-E-04,CEST-27-E-12,CEST-30-C-08,CEST-30-E-03,
   
CEST-34-C-06,CEST-34-F-04,CEST-35-G-09,CEST-36-A-01,CEST-36-B-01,
   
CEST-37-F-03,CEST-37-F-06,CEST-45-A-10,CEST-45-H-05,CEST-46-D-03,
   
CEST-46-D-11,CEST-48-D-01,CEST-48-E-01,CEST-50-E-09,CEST-51-A-01,
   
CEST-51-C-09,CEST-53-G-01,CEST-54-C-12,CEST-54-H-11,CEST-55-E-01,
   
CEST-55-G-06,CEST-57-C-12,CEST-57-E-12,CEST-59-F-05},{CEST-01-A-04}};

acontology=
{{AEST-01-A-01,blank,None,None},{AEST-01-A-02,CEST-01-A-01,
    enzyme / ion transporter,
    cell growth and/or maintenance / transport / ion
transport},{AEST-01-A-03,
    CEST-01-A-02,translation regulator / translation
factor,
    cell growth and/or maintenance / metabolism /
biosynthesis}};

outerindex = 1; innerindex = 1; While[outerindex ¡Ü
Length[acontology], \
While[innerindex ¡Ü Length[
    temp], If
[Length[Intersection[acontology[[outerindex]], 
    temp[[innerindex]]]] == 
      1, (acontology =
         Append[acontology[[outerindex]],
temp[[innerindex]]]; innerindex = \
Length[temp] + 1), innerindex++]]; outerindex++;
innerindex = 1];



The output I am hoping for is to progressively match
components of each list to output as follows:

Given input:
Append[acontology[[2]], temp[[1]]]

Desired output:
{AEST-01-A-02,CEST-01-A-01,enzyme / ion
transporter,cell growth and/or \
maintenance / transport / ion
transport,{CEST-01-A-01,CEST-17-A-06}}


When I have used various portions of the above nested
loops on their own, they seem to work, however things
break down once placed in a loop structure.  Any
thoughts on why a loop or Intersection might generate
the Nonatomic expression error??

Thanks for any advice you might have.

Best regards,
Todd



		
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• Follow-Ups:
  • Re: Nonatomic expression error encountered with Intersection
    • From: DrBob <drbob@bigfoot.com>