Mathematica 9 is now available
Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1999
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 1999

[Date Index] [Thread Index] [Author Index]

Search the Archive

Q: Union and SameTest Option

  • To: mathgroup at smc.vnet.net
  • Subject: [mg16016] Q: Union and SameTest Option
  • From: Clemens Frey <btml01 at uni-bayreuth.de>
  • Date: Sat, 20 Feb 1999 02:52:06 -0500
  • Sender: owner-wri-mathgroup at wolfram.com

Hi Mathematica-Groupers!

Can anybody explain to me what's going on here ? 

In[270]:=
Union[ {{a,b,1},{a,c,1},{x,y,2},{a,b,2}},
       SameTest->(#1[[2]]===#2[[2]]&) ]
Out[270]=
{{a,b,1},{a,c,1},{x,y,2}}

is ok since the first and the last list element have the same second
component. But what is wrong here now ?

In[272]:=
Union[ {{a,b,1},{a,c,1},{x,y,2},{a,b,2}},
       SameTest->(#1[[3]]===#2[[3]]&) ]
Out[272]=
{{a,b,1},{a,b,2},{a,c,1},{x,y,2}} 

Thanks in advance
Clemens

------------------------------------------------------------
Clemens Frey
Doctoral Student at the 
Department of Mathematics/BITOEK
University of Bayreuth(Germany)

clemens.frey at uni-bayreuth.de
http://www.bitoek.uni-bayreuth.de/~Clemens.Frey
------------------------------------------------------------



  • Prev by Date: rank of matrix in mathematica
  • Next by Date: Re: implementing a stack
  • Previous by thread: Re: rank of matrix in mathematica
  • Next by thread: Re: Q: Union and SameTest Option