61 lines
1.8 KiB
HTML
61 lines
1.8 KiB
HTML
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<!DOCTYPE HTML PUBLIC "-//W3O//DTD W3 HTML 2.0//EN">
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<!Originally converted to HTML using LaTeX2HTML 95 (Thu Jan 19 1995) by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds >
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<HEAD>
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<TITLE> nth (FUNCTION)</TITLE>
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</HEAD>
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<BODY>
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<meta name="description" value=" nth (FUNCTION)">
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<meta name="keywords" value="lp">
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<meta name="resource-type" value="document">
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<meta name="distribution" value="global">
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<P>
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<BR> <HR>
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<A HREF="node106.html"><IMG ALIGN=BOTTOM ALT="next" SRC="next_motif.gif"></A>
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<A HREF="node72.html"><IMG ALIGN=BOTTOM ALT="up" SRC="up_motif.gif"></A>
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<A HREF="node104.html"><IMG ALIGN=BOTTOM ALT="previous" SRC="previous_motif.gif"></A> <BR>
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<A HREF="lp.html"><B>Contents</B></A>
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<B> Next:</B>
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<A HREF="node106.html"> nthcdr (FUNCTION)</A>
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<B>Up:</B>
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<A HREF="node72.html"> Appendix: Selected Lisp </A>
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<B> Previous:</B>
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<A HREF="node104.html"> not (PREDICATE)</A>
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<BR> <HR> <P>
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<H1> nth (FUNCTION)</H1>
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<P>
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<b> Format:</b>
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<tt> (nth <index> <list> )</tt>
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<P>
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<b> Required arguments:</b>
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2
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<P>
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<tt> <index> </tt>: any expression which returns a positive integer (fixnum).
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<tt> <list> </tt>: any expression which returns a list.
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<P>
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The function nth returns the indexed element of <tt> <list> </tt>. <tt> <index> </tt> must
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be a non-negative integer. 0 indicates the first element of <tt> <list> </tt>,
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1 the second, etc. An index past the end of the list will cause nth to
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return nil.
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<P>
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<b> Examples:</b>
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<P>
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<BLOCKQUOTE>
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<PRE>> (nth 0 '(picard riker work crusher))
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PICARD
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> (nth 2 '((captain picard)
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(commander riker)
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(lieutenant worf)
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(ensign crusher)))
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(LIEUTENANT WORF)
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</PRE>
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</BLOCKQUOTE>
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<P>
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<BR> <HR>
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<P>
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<ADDRESS>
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<I>© Colin Allen & Maneesh Dhagat <BR>
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March 2007 </I>
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</ADDRESS>
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</BODY>
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