File r37/lisp/csl/html/r37_0511.html artifact 79d36a6841 part of check-in trunk

<A NAME=s_i>

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



<B>S_I</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
<P>
 
 <P>
<P>
The <em>s_i</em> operator returns the Sine Integral function si. 
<P>
<P>
 <P> <H3> 
syntax: </H3>
<em>s_i</em>(&lt;expression&gt;) 
<P>
<P>
<P>
 <P> <H3> 
examples: </H3>
<P><PRE><TT>
s_i(xx); 

  (2*Si(xx) - pi) / 2 


df(s_i(x),x); 

  sin(x) / x

</TT></PRE><P>The operator name <em>s_i</em> is simplified towards 
<A HREF=r37_0509.html>SI</A>. 
Since REDUCE is not case sensitive by default the name ``si'' can't be 
used. 
<P>
<P>
<P>