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<head><title>number -- count how many elements of a list satisfy a condition</title>
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<div><h1>number -- count how many elements of a list satisfy a condition</h1>
<div class="single"><h2>Description</h2>
<div><tt>number(x,f)</tt> the number of elements <tt>e</tt> of the list <tt>x</tt> for which <tt>f(e)</tt> is true.<p/>
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<div class="single"><h2>See also</h2>
<ul><li><span><a href="_positions_lp__Visible__List_cm__Function_rp.html" title="which elements of a list satisfy a condition">positions</a> -- which elements of a list satisfy a condition</span></li>
<li><span><a href="_select.html" title="select from a list, hash table, or string">select</a> -- select from a list, hash table, or string</span></li>
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