File r37/lisp/csl/html/r37_0087.html from the latest check-in

<A NAME=LN>

<TITLE>LN</TITLE></A>
<b><a href=r37_idx.html>INDEX</a></b><p><p>



<B>LN</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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syntax: </H3>
<em>ln</em>(&lt;expression&gt;) 
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&lt;expression&gt; can be any valid scalar REDUCE expression. 
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The <em>ln</em> operator returns the natural logarithm of its argument. 
However, unlike 
<A HREF=r37_0088.html>log</A>, there are no algebraic rules associated 
with it; it will only evaluate when 
<A HREF=r37_0330.html>rounded</A> is on, and the 
argument is a real number. 
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examples: </H3>
<P><PRE><TT>
ln(x); 

  LN(X) 


ln 4; 

  LN(4) 


ln(e); 

  LN(E) 


df(ln(x),x); 

  DF(LN(X),X) 


on rounded; 

ln 4; 

  1.38629436112 


ln e; 

  1

</TT></PRE><P>Because of the restricted algebraic properties of <em>ln</em>, use
rs are 
advised to use 
<A HREF=r37_0088.html>log</A> whenever possible. 
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