This is documentation for Mathematica 8, which was
based on an earlier version of the Wolfram Language.

# SortBy

 SortBy sorts the elements of list in the order defined by applying f to each of them.
• SortBy sorts the so that the lie in canonical order.
• If some of the are the same, then the canonical order of the corresponding is used.
• SortBy breaks ties by successively using the values obtained from the .
• SortBy uses the canonical ordering described in the notes for Sort.
• SortBy can be used on expressions with any head, not only List.
Sort a list of lists by the last element of each sublist:
Sort by the total of each sublist:
Sort a list of integers by their values modulo 3:
Sort a list of lists by the last element of each sublist:
 Out[1]=
Sort by the total of each sublist:
 Out[2]=

Sort a list of integers by their values modulo 3:
 Out[1]=
 Scope   (4)
Sort by numerical value:
The default order ranks these symbolically:
Sort by absolute numerical value:
Slightly faster way:
Sort by Re, Im, Arg, and Abs:
Sort by date:
SortBy can be used on expressions with any head:
 Applications   (2)
Show the top 10 countries according to different criteria:
Sort the first 10 countries in alphabetical order by population:
Sort the first 10 countries in alphabetical order by area:
Sort mathematically equivalent expressions by different criteria:
Sort by LeafCount:
Sort by size of error for numerical evaluation with machine numbers at :
SortBy is equivalent to Sort[{f[#], #}&/@e][[All, -1]]: