Re: Mapping tag-value lists to a third
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- Subject: [mg132456] Re: Mapping tag-value lists to a third
- From: carlos.felippa%colorado.edu at gtempaccount.com
- Date: Thu, 20 Mar 2014 05:27:45 -0400 (EDT)
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Thanks to all who replied. For now I have implemented it as
tagval=If [$VersionNumber>=5.1,Pick[val,tag,1],val*tag/. 0:>Sequence[]];
For big lists, Pick is slightly faster. Eg, for 10^7 length, on a MacPro:
Pick 1.45 sec Sequence: 1.72 sec
The reason for $VersionNumber is that Pick appeared in 5.1. Some
users of my Mathematica codes are colleagues living overseas who run
version 4 on old computers.