Re: Sort problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg81721] Re: Sort problem*From*: yatesd at mac.com*Date*: Tue, 2 Oct 2007 05:37:42 -0400 (EDT)*References*: <fdqd33$n6m$1@smc.vnet.net>

Sort by default will put the elements of the list into canonical order, which appears to be what you want. Namely: In[6]:= Sort[{{r, 2}, {a, 3}, {x, 4}}] Out[6]= {{a, 3}, {r, 2}, {x, 4}} This is equivalent functionally to Sort[{{r, 2}, {a, 3}, {x, 4}}, OrderedQ[{#1, #2}] &] although supplying your own sort function usually has a drastic impact on performance (noticeable on large lists). #1[[1]] < #2[[1]] & did not work because the 'Less' function (<) is not defined for strings. You can see this by trying to evaluate: In[9]:= {a, 3}[[1]] < {r, 2}[[1]] Out[9]= a < r Regards, Derek