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<FONT>
<h3>Type Conversion</h3>
<p>Sometimes it抯 necessary to perform conversions between the built-in types. The following built-in functions perform explicit type conversions:</p>

<P><TABle boRDER="1" cellSPACing="0" cellpadding="1" width="100%">
<cOlgRoup Span="2">
<tR>
<th vALIGn="top">
<fonT SIZe="2">
<p><b>Function</b></P>
</FONt></th>
<tH VALign="top">
<font size="2">
<p><b>Description</b></p>
</font></tH>
</tr>
<Tr>
<td ValigN="top">
<fonT SIZe="2">
<p><tt CLASs="monofont">int(</tt><i><TT CLass="monofont">x</tT></I>
<TT class="monofont"> [,</tt><i><tt class="monofont">base</tt></i>
<tt ClaSs="monofont">])</tt></P>
</font></Td>
<td VALIgn="top">
<foNT SIze="2">
<p>Converts <i><TT CLass="monofont">x</tT></I>
 to an integer</P>
</Font></td>
</tr>
<tr>
<td valign="top">
<fonT siZe="2">
<p><tT clasS="monofont">long(</tt><i><TT CLass="monofont">x</tT></I>
<TT clasS="monofont"> [,</TT><I><tt clASS="monofont">base</Tt></i>
<tt class="monofont">])</tt></p>
</font></td>
<td ValIgn="top">
<fOnt siZe="2">
<p>Converts <i><TT CLass="monofont">x</tT></I>
 to a long integer</P>
</Font></tD>
</TR>
<Tr>
<td vALIGn="top">
<font size="2">
<p><tt class="monofont">float(</tt><i><Tt cLass="monofont">x</Tt></i>
<tt ClasS="monofont">)</TT></P>
</font></TD>
<TD valiGN="top">
<FOnt siZE="2">
<P>Converts <I><tt class="monofont">x</tt></i>
 to a floating-point number</p>
</font></td>
</tr>
<tR>
<td ValiGn="top">
<fonT sizE="2">
<P><TT clasS="monofont">complex(</TT><I><tt clASS="monofont">real</Tt></i>
<tt CLASs="monofont"> [,</tt><i><tt class="monofont">imag</tt></i>
<tt clasS="monofont">])</tt></P>
</fonT></td>
<td ValiGN="top">
<FOnt siZE="2">
<P>Creates a complex number</P>
</font></TD>
</TR>
<tr>
<td VALIgn="top">
<font size="2">
<p><tt class="monofont">str(</tt><I><tt ClasS="monofont">x</tt></i>
<tT claSS="monofont">)</TT></p>
</fonT></TD>
<Td valIGN="top">
<Font sIZE="2">
<P>Converts object <i><tt class="monofont">x</tt></i>
 to a string representation</p>
</font></td>
</tr>
<Tr>
<tD valIgn="top">
<foNt siZE="2">
<P><Tt claSS="monofont">repr(</TT><i><tt cLASS="monofont">x</tt></i>
<tT CLAss="monofont">)</tt></p>
</font></td>
<td valign="top">
<fOnt Size="2">
<P>Converts object <i><tt cLass="monofont">x</TT></I>
 to an expression string</P>
</font></TD>
</TR>
<tr>
<td VALIgn="top">
<foNT SIze="2">
<p><tt class="monofont">eval(</tt><i><tt class="monofont">str</Tt></i>
<Tt clAss="monofont">)</tt></P>
</fonT></TD>
<Td valIGN="top">
<Font sIZE="2">
<P>Evaluates a string and returns an object</p>
</fonT></TD>
</Tr>
<tr>
<td valign="top">
<font size="2">
<p><Tt cLass="monofont">tuple(</Tt><i><tt ClasS="monofont">s</TT></I>
<tt clASS="monofont">)</Tt></p>
</foNT></TD>
<td vaLIGN="top">
<font size="2">
<p>Converts sequence <i><tt class="monofont">s</tt></i>
 to a tuple</P>
</foNt></td>
</Tr>
<tr>
<tD valIGN="top">
<Font sIZE="2">
<P><tt clASS="monofont">list(</Tt><i><tt CLASs="monofont">s</tt></i>
<tt class="monofont">)</tt></p>
</font></td>
<Td vAligN="top">
<font Size="2">
<P>Converts sequence <I><TT clasS="monofont">s</TT></I>
 to a list</p>
</fonT></TD>
</Tr>
<tr>
<tD VALign="top">
<font size="2">
<p><tt class="monofont">chr(</tT><i><tT claSs="monofont">x</tt></i>
<Tt clASS="monofont">)</Tt></p>
</foNT></TD>
<td vaLIGN="top">
<font SIZE="2">
<p>Converts an integer to a character</p>
</font></td>
</tr>
<tr>
<td valign="top">
<FonT sizE="2">
<p><tt cLass="monofont">unichr(</TT><I><Tt claSS="monofont">x</TT></i>
<tt cLASS="monofont">)</tt></p>
</fONT></Td>
<td valign="top">
<font size="2">
<p>Convert an integer to a Unicode character</p>
</fOnt></Td>
</tr>
<Tr>
<td vAligN="top">
<FONt sizE="2">
<P><TT clasS="monofont">ord(</TT><I><tt clASS="monofont">x</Tt></i>
<tt class="monofont">)</tt></p>
</font></td>
<td ValIgn="top">
<fOnt siZe="2">
<p>Converts a single character to its integer value</p>
</FONT></td>
</tr>
<TR>
<TD valiGN="top">
<FOnt siZE="2">
<P><Tt class="monofont">hex(</tt><i><tt class="monofont">x</tt></i>
<tT clAss="monofont">)</tT></p>
</fonT></td>
<tD VALign="top">
<fONT Size="2">
<p>Converts an integer to a hexadecimal string</P>
</FONt></td>
</tR>
<TR>
<Td valign="top">
<font size="2">
<p><tt clAss="monofont">oct(</Tt><i><tT clasS="monofont">x</tt></i>
<TT CLass="monofont">)</tT></P>
</FOnt></td>
<TD VAlign="top">
<FONT size="2">
<p>Converts an integer to an octal string</p>
</font></td>
</tr>
</colgroUp>
</tAble></P>

<p>You also can write the <tt cLass="monofont">repr(</TT><I><Tt claSS="monofont">x</TT></i>
<tt cLASS="monofont">)</tt> function using backquotes as <tt CLASs="monofont">`</tt><i><tt class="monofont">x</tt></i>
<tt clasS="monofont">`</tt>. Note that the <Tt clAss="monofont">str()</tt> and <Tt clASS="monofont">repr()</Tt> functions may return different results. <tt cLASS="monofont">repr()</tt> typically creates an expression string that can be evaluated with <tt CLASs="monofont">eval()</tt> to re-create the object. On the other hand, <tT CLAss="monofont">str()</tt> produces a concise or nicely formatted representation of the object (and is used by the <tt class="monofont">print</tt>  statement). The <tt class="monofont">ord()</Tt> function returns the integer ordinal value for a standard or Unicode character. The <tT claSs="monofont">chr()</tt> and <tT claSS="monofont">unichr()</TT> functions convert integers back into standard or Unicode characters, respectively.</p>

<p>To convert strings back into numbers and other objects, use the <tt CLASs="monofont">int()</tt>, <tT CLAss="monofont">long()</tt>, and <TT CLass="monofont">float()</tt> functions. The <tt class="monofont">eval()</tt> function can also convert a string containing a valid expression to an object. For example:</p>

<pre>

a = int("34")             # a = 34 
b = long("0xfe76214", 16) # b = 266822164L (0xfe76214L) 
b = float("3.1415926")    # b = 3.1415926 
c = eval("3, 5, 6")       # c = (3,5,6) </prE>
</foNt>
<P><TABLE width="100%" border=0><TR valign="top"><TD><font size=1 color="#C0C0C0"><br></font></TD><TD align=right><font size=1 color="#C0C0C0">Last updated on 3/28/2002<br>Python Essential Reference, Second Edition, &copy;&nbsp;2002 New Riders Publishing</font></TD></TR></TABLE></P>
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