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<p>&nbsp;<p>
<hr noshade size="5">
<h2><a name="Log"></a>
Log
</h2>

Returns the principal value of the natural logarithm.

<p><p>

<h3>
Syntax:
</h3>
<pre>y := Log(x);
y := Log(b,x);</pre>

<p>

<table>
<tr>
<td>complex or real</td>
<td><pre>  y  </pre></td>
<td></td>
</tr>
<tr>
<td>complex or real or rational or integer</td>
<td><pre>  x  </pre></td>
<td></td>
</tr>
<tr>
<td>complex or real or rational or integer</td>
<td><pre>  b  </pre></td>
<td></td>
</tr>
</table>

<p>


See also:&nbsp;&nbsp;<a href="kashref.html#Exp">Exp</a>

<p>

<h3>
Description:
</h3>
Given <tt> x</tt>>0 in Z, Q or R the function returns
the natural logarithm of <tt> x</tt>. For <tt> x</tt>=|<tt> x</tt>|e^{i\phi}
\inC\setminusR^{ &gt;=  0}, \phi\in (-\pi,\pi],
the function returns <tt> y</tt>=\log|<tt> x</tt>|+i\arg <tt> x</tt>.
The computation is done
in the current precision of the real (complex) field.

If two arguments are given the first is used as the base of the
logarithm.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>

<pre>

kash> Log(2);
0.6931471805599453094172321214581765680755001343602553
kash> Log(-2);
0.6931471805599453094172321214581765680755001343605 + 3.1415926535897932384626\
43383279502884197169399375*i
kash> i := Comp(0, 1);
1*i
kash> Log(i);
> 1.570796326794896619231321691639751442098584699688*i

</pre>

<p>


<hr>

<p>
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