MATLAB Function Reference 
Sort array elements in ascending or descending order
Syntax
Description
B = sort(A)
sorts the elements along different dimensions of an array, and arranges those elements in ascending order.
Integer, real, logical, and character arrays are permitted. Floatingpoint arrays can be complex. For elements of A with identical values, the order of these elements is preserved in the sorted list. When A
is complex, the elements are sorted by magnitude, i.e., abs(A)
, and where magnitudes are equal, further sorted by phase angle, i.e., angle(A)
, on the interval . If A
includes any NaN
elements, sort
places these at the high end.
B = sort(A,dim)
sorts the elements along the dimension of A
specified by a scalar dim
.
B = sort(...,mode)
sorts the elements in the specified direction, depending on the value of mode
.
'ascend' 
Ascending order (default) 
'descend' 
Descending order 
[B,IX] = sort(A,...)
also returns an array of indices IX
, where size(IX) == size(A)
. If A
is a vector, B = A(IX)
. If A
is an m
byn
matrix, then each column of IX
is a permutation vector of the corresponding column of A
, such that
If A
has repeated elements of equal value, the returned indices preserve the original ordering.
Sorting Complex Entries
If A
has complex entries r
and s
, sort
orders them according to the following rule: r
appears before s
in sort(A)
if either of the following hold:
v = [1 1 i i]; angle(v) ans = 0 3.1416 1.5708 1.5708 sort(v) ans = 0  1.0000i 1.0000 0 + 1.0000i 1.0000
Note
sort uses a different rule for ordering complex numbers than do max and min , or the relational operators < and >. See the Relational Operators reference page for more information.

Examples
Example 1. This example sorts a matrix A
in each dimension, and then sorts it a third time, requesting an array of indices for the sorted result.
A = [ 3 7 5 0 4 2 ]; sort(A,1) ans = 0 4 2 3 7 5 sort(A,2) ans = 3 5 7 0 2 4 [B,IX] = sort(A,2) B = 3 5 7 0 2 4 IX = 1 3 2 1 3 2
Example 2. This example sorts each column of a matrix in descending order.
See Also
issorted
, max
, mean
, median
, min
, sortrows
smooth3  sortrows 
© 19942005 The MathWorks, Inc.