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<A NAME=DET>

<TITLE>DET</TITLE></A>
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<B>DET</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>det</em> operator returns the determinant of its 
(square 
<A HREF=r37_0345.html>matrix</A>) argument. 
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syntax: </H3>
<em>det</em>(&lt;expression&gt;) or <em>det</em> &lt;expression&gt; 
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&lt;expression&gt; must evaluate to a square matrix. 
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examples: </H3>
<P><PRE><TT>

matrix m,n; 


m := mat((a,b),(c,d)); 

  M(1,1) := A
  M(1,2) := B
  M(2,1) := C
  M(2,2) := D
                                 


det m; 

  A*D - B*C 


n := mat((1,2),(1,2)); 

  N(1,1) := 1
  N(1,2) := 2
  N(2,1) := 1
  N(2,2) := 2
                                 



det(n); 

  0 



det(5); 

  5

</TT></PRE><P>Given a numerical argument, <em>det</em> returns the number. Howev
er, given a 
variable name that has not been declared of type matrix, or a non-square 
matrix, <em>det</em> returns an error message. 
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