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Selecting Rows Based on Column Values

• To: mathgroup at smc.vnet.net
• Subject: [mg101471] Selecting Rows Based on Column Values
• From: cynthia wu <wu.x.cynthia at gmail.com>
• Date: Wed, 8 Jul 2009 07:10:21 -0400 (EDT)

I've been trying to use the Select Command to select only the rows
that have the a specific value in a specific column.  I have, for
example, the following matrix (4x3):

tester={{1, 3, 1}, {3, 1, 0}, {4, 2, 1}, {5, 6, 2}}

I want to select the rows that have values ==1 in the 3rd column.
I've tried:

select(tester, #[[All,3]]==1&), but I get an error saying that my
request violates the matrix boundaries.

The desired output should be: {{1,3,1}, {4,2,1}}.

Any thoughts would be greatly appreciated.  Thanks!

• Follow-Ups:
  • Re: Selecting Rows Based on Column Values
    • From: "Elton Kurt TeKolste" <tekolste@fastmail.us>
  • Re: Selecting Rows Based on Column Values
    • From: Leonid Shifrin <lshifr@gmail.com>
  • Re: Selecting Rows Based on Column Values
    • From: Syd Geraghty <sydgeraghty@me.com>
  • Re: Selecting Rows Based on Column Values
    • From: Adriano Pascoletti <adriano.pascoletti@dimi.uniud.it>
  • Re: Selecting Rows Based on Column Values
    • From: Thomas Dowling <thomasgdowling@gmail.com>
  • Re: Selecting Rows Based on Column Values
    • From: Tomas Garza <tgarza10@msn.com>
  • Re: Selecting Rows Based on Column Values
    • From: Yasvir Tesiram <tesiramy@omrf.org>