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<A NAME=MODULAR>

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



<B>MODULAR</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>switch</B><P>
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When <em>modular</em> is on, polynomial coefficients are reduced by the 
modulus set by 
<A HREF=r37_0104.html>setmod</A>. If no modulus has been set, <em>modular</em> 
has no effect. 
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 <P> <H3> 
examples: </H3>
<P><PRE><TT>
setmod 2; 

  1 


on modular; 

(x+y)**2; 

   2    2
  X  + Y  


145*x**2 + 20*x**3 + 17 + 15*x*y;
			 


   2
  X  + X*Y + 1

</TT></PRE><P>Modular operations are only conducted on the coefficients, not the
 
exponents. The modulus is not restricted to being prime. When the modulus 
is prime, division by a number not relatively prime to the modulus results 
in a &lt;Zero divisor&gt; error message. When the modulus is a composite 
number, division by a power of the modulus results in an error message, but 
division by an integer which is a factor of the modulus does not. 
The representation of modular number can be influenced by 

<A HREF=r37_0269.html>balanced_mod</A>. 
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