
<A NAME=SIGN>

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



<B>SIGN</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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syntax: </H3>
<em>sign</em>&lt;expression&gt; 
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<em>sign</em>tries to evaluate the sign of its argument. If this 
is possible <em>sign</em> returns one of 1, 0 or -1. Otherwise, the result 
is the original form or a simplified variant. 
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examples: </H3>
<P><PRE><TT>
        sign(-5) 

  -1


        sign(-a^2*b) 

  -SIGN(B)

</TT></PRE><P>Even powers of formal expressions are assumed to be positive only 
as long 
as the switch 
<A HREF=r37_0274.html>complex</A> is off. 
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