File r37/lisp/csl/html/r37_0497.html artifact 7e644fc907 part of check-in 52fc28dabe



<A NAME=Lambert_W_function>

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



<B>LAMBERT\_W FUNCTION</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
<P>
 
Lambert's W function is the inverse of the function w * e**w. 
It is used in the 
<A HREF=r37_0179.html>solve</A> package for equations containing 
exponentials and logarithms. 
<P>
<P>
 <P> <H3> 
syntax: </H3>
<em>Lambert_W</em>(&lt;z&gt;) 
<P>
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>
Lambert_W(-1/e); 

  -1 


solve(w + log(w),w); 

  w=lambert_w(1)


on rounded; 

Lambert_W(-0.05); 

  - 0.0527059835515

</TT></PRE><P>The current implementation will compute the principal branch in 
rounded mode only. 
<P>
<P>
<P>


REDUCE Historical
REDUCE Sourceforge Project | Historical SVN Repository | GitHub Mirror | SourceHut Mirror | NotABug Mirror | Chisel Mirror | Chisel RSS ]