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<FONT><h3>The String Group</h3>
<p>This group is responsible for many kinds of string services available. These modules provide access to several types of string manipulation operations.</p>
<P>Note that since release 2.0, all these functions are tied directly to <I>string</I> objects, as methods. The <Tt claSS="monofont">string</TT> module is still around only for backward compatibility.</p>
<h4><tt CLASs="monofont">string</tt></h4>
<p>The <tt class="monofont">string</tt> module supports common string operations by providing several functions and constants that manipulate Python strings.</p>
<h5><tt clAss="monofont">string.split()</Tt></h5>
<p>This function splits a <Tt claSs="monofont">string</tt> into a list. If the <TT CLass="monofont">delimiter</tT> is omitted, <TT Class="monofont">white-spaces</TT> are used.</P>
<P><a namE="idx1073742752"></A>basic syntax: <TT class="monofont">string.split(</tt><i><tt class="monofont">string [,delimiter]</tt></i><tt ClaSs="monofont">)</tt></P>
<pre>
>>> print string,split("a b c")
["a","b","c"]
</pRe>
<h5><tT CLAss="monofont">string.atof()</tt></H5>
<P>It converts a <TT clasS="monofont">string</TT> to a floating number.</P>
<p><a naME="idx1073742753"></A>basic syntax: <Tt class="monofont">string.atof(string)<a name="idx1073742754"></a><a name="idx1073742755"></a><a nAme="idx1073742756"></A><a naMe="idx1073742757"></a></tt></P>
<h5><tt CLASs="monofont">string.atoi()</tt></h5>
<P>It converts a <TT Class="monofont">string</TT> to an integer. <TT clasS="monofont">atoi</TT> takes an optional second argument: <Tt class="monofont">base.</tt> If omitted, the start of the string (for instance, <tt class="monofont">0x</tt> for hexadecimal) is used to determine the base.</p>
<p><a NamE="idx1073742758"></a>basic syntax: <tt Class="monofont">string.atoi(</Tt><i><tT CLAss="monofont">string[, base]</tt></I><TT Class="monofont">)</TT></P>
<H5><tt clASS="monofont">string.atol()</Tt></h5>
<p>It converts a <tt class="monofont">string</tt> to a long integer. <tt class="monofont">atol</tT> takes an optional second argument: <tt ClasS="monofont">base.</tt> If omitted, the start of the string (for instance, <tt ClasS="monofont">0x</TT> for hexadecimal) is used to determine the basic syntax: <Tt claSS="monofont">string.atol(string[, base])</TT></p>
<h5><tt CLASs="monofont">string.upper()</tt></h5>
<P>It converts a <TT Class="monofont">string</tt> to uppercase.</p>
<p><a name="idx1073742759"></a>basic syntax: <tt clasS="monofont">string.upper(</tt><I><tt cLass="monofont">string</tT></i><tt CLASs="monofont">)</tt></p>
<H5><TT Class="monofont">string.find()</TT></H5>
<P>It returns the index position of the <tt clASS="monofont">substring</Tt> within <tt class="monofont">string.</tt> Optionally, you can specify the string's range that should be used in the search.</p>
<p><a name="idx1073742760"></a>basic syntax: <tt ClaSs="monofont">string.find(</tt><I><tt clAss="monofont">string, substring[, start [,end]]</tT></I><TT clasS="monofont">)</TT></P>
<h5><tt cLASS="monofont">string.join()</tt></h5>
<p>This function joins the <I>string</I> elements of a <I><Tt class="monofont">list</tt></i> using <tt class="monofont">separator</tt> to separate them.</p>
<p><A naMe="idx1073742761"></a>basic syntax: <tT clasS="monofont">string.join(</tt><i><TT CLass="monofont">list, separator</tT></I><TT clasS="monofont">)</TT></P>
<h5><tt cLASS="monofont">string.capitalize()</tt></h5>
<p>It capitalizes the first character of <i><tt class="monofont">string.</tt></i></p>
<p><a naMe="idx1073742762"></a>basic syntax: <Tt clAss="monofont">string.capitalize(</tt><I><tt cLASS="monofont">string</tt></i><tT CLAss="monofont">)</tt></P>
<H5><TT clasS="monofont">string.capwords()</TT></H5>
<p>This function capitalizes the first letter of each word in <tt class="monofont">string</tt> and removes repeated, leading, and trailing whitespace.</p>
<p><a name="idx1073742763"></a>basic syntax: <tt ClaSs="monofont">string.capwords(</tt><I><tt clAss="monofont">string</tT></I><TT clasS="monofont">)</TT></P>
<h5><tt cLASS="monofont">string.lower()</tt></h5>
<p>It converts all characters in <TT CLass="monofont">string</tt> to lowercase.<a name="idx1073742764"></a><a name="idx1073742765"></a><a naMe="idx1073742766"></a><A namE="idx1073742767"></a></p>
<p><a Name="idx1073742768"></A>basic syntax: <TT Class="monofont">string.lower(</TT><I><Tt claSS="monofont">string</TT></i><tt cLASS="monofont">)</tt></p>
<h5><tt class="monofont">string.lstrip(),<a name="idx1073742769"></a><a naMe="idx1073742770"></a>string.rstrip()</Tt> and <tt Class="monofont">string.strip()</Tt></h5>
<p>These functions remove leading and/or trailing whitespace from <I><TT Class="monofont">string.</TT></I></P>
<p><a naME="idx1073742771"></A><A name="idx1073742772"></A><A NAme="idx1073742773"></a>basic syntaxes:</p>
<pre>
string.lstrip(<i>string</i>)
string.rstrip(<i>string</i>)
string.strip(<i>string</i>)
</pre>
<h5><tt cLasS="monofont">string.ljust(),<a naMe="idx1073742774"></a><a nAme="idx1073742775"></a>string.rjust()</TT> and <TT clasS="monofont">string.center()</TT></H5>
<p>These functions define the alignment of <i><tt CLASs="monofont">string</tt></i> within a variable of <I><TT Class="monofont">width</tt></i> characters.</p>
<p><a name="idx1073742776"></a><a name="idx1073742777"></A><a nAme="idx1073742778"></a>basic syntaxes:</P>
<pre>
string.ljust(<i>string, width</I>)
string.rjust(<i>string, width</i>)
string.center(<i>string, width</I>)
</PRE>
<h5><tt cLASS="monofont">string.replace()</tt></h5>
<p>It replaces a <I><TT Class="monofont">maximum</TT></I> number of occurrences of <I><tt class="monofont">oldtext</tt></i> with <i><tt class="monofont">newtext</tt></I> in <i><tT claSs="monofont">string.</tt></i> If <I><tt cLASS="monofont">maximum</tt></i> is omitted, all occurrences are replaced.</p>
<P><A NAme="idx1073742779"></a>basic syntax: <tT CLAss="monofont">string.replace(</tt><I><TT Class="monofont">string, oldtext, newtext [,maximum]</tt></i><tt class="monofont">)</tt></p>
<h5><tt ClaSs="monofont">string.zfill()</tt></H5>
<p>It inserts zeros on the left side of a <tt cLass="monofont">string</TT> that has <TT clasS="monofont">width</TT> characters.</P>
<p><a naME="idx1073742780"></A>basic syntax: <Tt claSS="monofont">string.zfill(</TT><i><tt class="monofont">string, width</tt></i><tt class="monofont">)</tt></P>
<p>Next, I list a few constants that can be used to test whether a certain variable is part of a specific domain:</p>
<Pre>
>>> import string
>>> string.digits
"0123456789"
>>> string.octdigits
"01234567"
>>> string.uppercase
"ABCDEFGHIJKLMNOPQRSTUVWXY"
>>> string.hexdigits
"0123456789abcdefABCDEF"
>>> string.lowercase
"abcdefghijklmnopqrstuvwxy"
</pRe>
<p>Let's write an example that uses <a nAme="idx1073742781"></a><A NAMe="idx1073742782"></a><tt CLASs="monofont">string.uppercase:</tt><a NAME="idx1073742783"></a><a naME="idx1073742784"></A><A name="idx1073742785"></a><a name="idx1073742786"></a></p>
<pre>
>>> text = "F"
>>> if text in string.uppercase:
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