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<head><title>unique -- eliminate duplicates from a list</title>
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<div><a href="index.html" title="">Macaulay2Doc</a> > <a href="___The_sp__Macaulay2_splanguage.html" title="">The Macaulay2 language</a> > <a href="_lists_spand_spsequences.html" title="">lists and sequences</a> > <a href="_unique.html" title="eliminate duplicates from a list">unique</a></div>
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<div><h1>unique -- eliminate duplicates from a list</h1>
<div class="single"><h2>Description</h2>
<div><tt>unique v</tt> yields the elements of the list <tt>v</tt>, without duplicates.<p/>
<table class="examples"><tr><td><pre>i1 : unique {3,2,1,3,2,4,a,3,2,3,-2,1,2,4}
o1 = {3, 2, 1, 4, a, -2}
o1 : List</pre>
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The order of elements is maintained. For something that might be slightly faster, but doesn't maintain the order of the elements, and may different answers, try making a set and then getting its elements.<table class="examples"><tr><td><pre>i2 : toList set {3,2,1,3,2,4,a,3,2,3,-2,1,2,4}
o2 = {1, 2, 3, 4, a, -2}
o2 : List</pre>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_sort.html" title="sort a list or columns of a matrix">sort</a> -- sort a list or columns of a matrix</span></li>
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<div class="waystouse"><h2>Ways to use <tt>unique</tt> :</h2>
<ul><li>unique(List)</li>
<li>unique(Sequence)</li>
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