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<A NAME=VAROPT>

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



<B>VAROPT</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>switch</B><P>
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When <em>varopt</em> is on, the sequence of variables is optimized by 

<A HREF=r37_0179.html>solve</A> with respect to execution speed. Otherwise, the 
sequence 
given in the call to 
<A HREF=r37_0179.html>solve</A> is preserved. Default is <em>on</em>. 
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In combination with the switch 
<A HREF=r37_0268.html>arbvars</A>, <em>varopt</em> can be used 
to control variable elimination. 
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 <P> <H3> 
examples: </H3>
<P><PRE><TT>
off arbvars; 

solve({x+2z,x-3y},{x,y,z});				

           x      x
  		   {{y=-,z= - -}} 
           3      2


solve({x*y=1,z=x},{x,y,z});				

               1
  		   {{z=x,y=-}} 
               x


off varopt; 

solve({x+2z,x-3y},{x,y,z});				

                       2*z
  		   {{x= - 2*z,y= - ---}} 
                        3


solve({x*y=1,z=x},{x,y,z});				

           1
  		   {{y=-,x=z}} 
           z

</TT></PRE><P>