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<title>4.5 fpformat -- Floating point conversions
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<H1><A NAME=
"SECTION006500000000000000000">
4.5 <tt class=
"module">fpformat
</tt> --
Floating point conversions
</A>
<A NAME=
"module-fpformat"></A>
The
<tt class=
"module">fpformat
</tt> module defines functions for dealing with
floating point numbers representations in
100% pure
Python.
<span class=
"note"><b class=
"label">Note:
</b>
This module is unneeded: everything here could
be done via the
<code>%
</code> string interpolation operator.
</span>
The
<tt class=
"module">fpformat
</tt> module defines the following functions and an
<dl><dt><table cellpadding=
"0" cellspacing=
"0"><tr valign=
"baseline">
<td><nobr><b><tt id='l2h-
950' xml:id='l2h-
950'
class=
"function">fix
</tt></b>(
</nobr></td>
<td><var>x, digs
</var>)
</td></tr></table></dt>
Format
<var>x
</var> as
<code>[-]ddd.ddd
</code> with
<var>digs
</var> digits after the
point and at least one digit before.
If
<code><var>digs
</var> <=
0</code>, the decimal point is suppressed.
<var>x
</var> can be either a number or a string that looks like
one.
<var>digs
</var> is an integer.
Return value is a string.
<dl><dt><table cellpadding=
"0" cellspacing=
"0"><tr valign=
"baseline">
<td><nobr><b><tt id='l2h-
951' xml:id='l2h-
951'
class=
"function">sci
</tt></b>(
</nobr></td>
<td><var>x, digs
</var>)
</td></tr></table></dt>
Format
<var>x
</var> as
<code>[-]d.dddE[+-]ddd
</code> with
<var>digs
</var> digits after the
point and exactly one digit before.
If
<code><var>digs
</var> <=
0</code>, one digit is kept and the point is suppressed.
<var>x
</var> can be either a real number, or a string that looks like
one.
<var>digs
</var> is an integer.
Return value is a string.
<dl><dt><b><span class=
"typelabel">exception
</span> <tt id='l2h-
952' xml:id='l2h-
952'
class=
"exception">NotANumber
</tt></b></dt>
Exception raised when a string passed to
<tt class=
"function">fix()
</tt> or
<tt class=
"function">sci()
</tt> as the
<var>x
</var> parameter does not look like a number.
This is a subclass of
<tt class=
"exception">ValueError
</tt> when the standard
exceptions are strings. The exception value is the improperly
formatted string that caused the exception to be raised.
<div class=
"verbatim"><pre>
>>> import fpformat
>>> fpformat.fix(
1.23,
1)
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<span class=
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2.4.2, documentation updated on
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2005.
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