
<A NAME=minussign>

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



<B>-</B> _ _ _ <B>MINUSSIGN</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>-</em> operator is a prefix or infix binary subtraction operator, as wel
l 
as the unary minus operator. 
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 <P> <H3> 
syntax: </H3>
&lt;expression&gt; <em>-</em> &lt;expression&gt; 
or <em>-</em>(&lt;expression&gt;,&lt;expression&gt;) 
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&lt;expression&gt; may be any valid REDUCE expression. 
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 <P> <H3> 
examples: </H3>
<P><PRE><TT>
15 - 4; 

  11 


x*(-5); 

  - 5*X 


a - b - 15; 

  A - B - 15 


-(a,4); 

  A - 4

</TT></PRE><P>The subtraction operator is left associative, so that a - b - c is
 equivalent 
to (a - b) - c, as shown in the third example. The subtraction operator is 
also valid with 
<A HREF=r37_0345.html>matrix</A> expressions of the correct dimensions 
and with 
<A HREF=r37_0045.html>equation</A>s. 
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