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<div class="textblock"><p>Section: <a class="el" href="sec_array.html">Array Generation and Manipulations</a> </p>
<h1><a class="anchor" id="Usage"></a>
Usage</h1>
<p>Sorts an n-dimensional array along the specified dimensional. The first form sorts the array along the first non-singular dimension. </p>
<pre class="fragment"> B = sort(A)
</pre><p> Alternately, the dimension along which to sort can be explicitly specified </p>
<pre class="fragment"> B = sort(A,dim)
</pre><p> FreeMat does not support vector arguments for <code>dim</code> - if you need <code>A</code> to be sorted along multiple dimensions (i.e., row first, then columns), make multiple calls to <code>sort</code>. Also, the direction of the sort can be specified using the <code>mode</code> argument </p>
<pre class="fragment"> B = sort(A,dim,mode)
</pre><p> where <code>mode = 'ascend'</code> means to sort the data in ascending order (the default), and <code>mode = 'descend'</code> means to sort the data into descending order.</p>
<p>When two outputs are requested from <code>sort</code>, the indexes are also returned. Thus, for </p>
<pre class="fragment"> [B,IX] = sort(A)
[B,IX] = sort(A,dim)
[B,IX] = sort(A,dim,mode)
</pre><p> an array <code>IX</code> of the same size as <code>A</code>, where <code>IX</code> records the indices of <code>A</code> (along the sorting dimension) corresponding to the output array <code>B</code>.</p>
<p>Two additional issues worth noting. First, a cell array can be sorted if each cell contains a <code>string</code>, in which case the strings are sorted by lexical order. The second issue is that FreeMat uses the same method as MATLAB to sort complex numbers. In particular, a complex number <code>a</code> is less than another complex number <code>b</code> if <code>abs(a) < abs(b)</code>. If the magnitudes are the same then we test the angle of <code>a</code>, i.e. <code>angle(a) < angle(b)</code>, where <code>angle(a)</code> is the phase of <code>a</code> between <code>-pi,pi</code>. </p>
<h1><a class="anchor" id="Example"></a>
Example</h1>
<p>Here are some examples of sorting on numerical arrays.</p>
<pre class="fragment">--> A = int32(10*rand(4,3))
A =
8 2 8
0 5 5
2 5 7
3 7 1
--> [B,IX] = sort(A)
B =
0 2 1
2 5 5
3 5 7
8 7 8
IX =
2 1 4
3 2 2
4 3 3
1 4 1
--> [B,IX] = sort(A,2)
B =
2 8 8
0 5 5
2 5 7
1 3 7
IX =
2 1 3
1 2 3
1 2 3
3 1 2
--> [B,IX] = sort(A,1,'descend')
B =
8 7 8
3 5 7
2 5 5
0 2 1
IX =
1 4 1
4 2 3
3 3 2
2 1 4
</pre><p>Here we sort a cell array of strings.</p>
<pre class="fragment">--> a = {'hello','abba','goodbye','jockey','cake'}
a =
[hello] [abba] [goodbye] [jockey] [cake]
--> b = sort(a)
b =
[abba] [cake] [goodbye] [hello] [jockey]
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