/usr/share/doc/python-pint-doc/html/measurement.html is in python-pint-doc 0.7.2-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Using Measurements — pint 0.7.2 documentation</title>
<link rel="stylesheet" href="_static/flasky.css" type="text/css" />
<link rel="stylesheet" href="_static/pygments.css" type="text/css" />
<script type="text/javascript">
var DOCUMENTATION_OPTIONS = {
URL_ROOT: './',
VERSION: '0.7.2',
COLLAPSE_INDEX: false,
FILE_SUFFIX: '.html',
HAS_SOURCE: true
};
</script>
<script type="text/javascript" src="_static/jquery.js"></script>
<script type="text/javascript" src="_static/underscore.js"></script>
<script type="text/javascript" src="_static/doctools.js"></script>
<link rel="top" title="pint 0.7.2 documentation" href="index.html" />
<link rel="next" title="Defining units" href="defining.html" />
<link rel="prev" title="Contexts" href="contexts.html" />
<link media="only screen and (max-device-width: 480px)" href="_static/small_flask.css" type= "text/css" rel="stylesheet" />
</head>
<body role="document">
<div class="related" role="navigation" aria-label="related navigation">
<h3>Navigation</h3>
<ul>
<li class="right" style="margin-right: 10px">
<a href="genindex.html" title="General Index"
accesskey="I">index</a></li>
<li class="right" >
<a href="defining.html" title="Defining units"
accesskey="N">next</a> |</li>
<li class="right" >
<a href="contexts.html" title="Contexts"
accesskey="P">previous</a> |</li>
<li class="nav-item nav-item-0"><a href="index.html">pint 0.7.2 documentation</a> »</li>
</ul>
</div>
<div class="document">
<div class="documentwrapper">
<div class="bodywrapper">
<div class="body" role="main">
<div class="section" id="using-measurements">
<span id="measurement"></span><h1>Using Measurements<a class="headerlink" href="#using-measurements" title="Permalink to this headline">¶</a></h1>
<p>Measurements are the combination of two quantities: the mean value and the error (or uncertainty). The easiest ways to generate a measurement object is from a quantity using the <cite>plus_minus</cite> operator.</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="kn">import</span> <span class="nn">numpy</span> <span class="k">as</span> <span class="nn">np</span>
<span class="gp">>>> </span><span class="kn">from</span> <span class="nn">pint</span> <span class="k">import</span> <span class="n">UnitRegistry</span>
<span class="gp">>>> </span><span class="n">ureg</span> <span class="o">=</span> <span class="n">UnitRegistry</span><span class="p">()</span>
<span class="gp">>>> </span><span class="n">book_length</span> <span class="o">=</span> <span class="p">(</span><span class="mf">20.</span> <span class="o">*</span> <span class="n">ureg</span><span class="o">.</span><span class="n">centimeter</span><span class="p">)</span><span class="o">.</span><span class="n">plus_minus</span><span class="p">(</span><span class="mf">2.</span><span class="p">)</span>
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">book_length</span><span class="p">)</span>
<span class="go">(20.0 +/- 2.0) centimeter</span>
</pre></div>
</div>
<p>You can inspect the mean value, the absolute error and the relative error:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">book_length</span><span class="o">.</span><span class="n">value</span><span class="p">)</span>
<span class="go">20.0 centimeter</span>
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">book_length</span><span class="o">.</span><span class="n">error</span><span class="p">)</span>
<span class="go">2.0 centimeter</span>
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">book_length</span><span class="o">.</span><span class="n">rel</span><span class="p">)</span>
<span class="go">0.1</span>
</pre></div>
</div>
<p>You can also create a Measurement object giving the relative error:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="n">book_length</span> <span class="o">=</span> <span class="p">(</span><span class="mf">20.</span> <span class="o">*</span> <span class="n">ureg</span><span class="o">.</span><span class="n">centimeter</span><span class="p">)</span><span class="o">.</span><span class="n">plus_minus</span><span class="p">(</span><span class="o">.</span><span class="mi">1</span><span class="p">,</span> <span class="n">relative</span><span class="o">=</span><span class="kc">True</span><span class="p">)</span>
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="n">book_length</span><span class="p">)</span>
<span class="go">(20.0 +/- 2.0) centimeter</span>
</pre></div>
</div>
<p>Measurements support the same formatting codes as Quantity. For example, to pretty print a measurement with 2 decimal positions:</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="s1">'{:.02fP}'</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">book_length</span><span class="p">))</span>
<span class="go">(20.00 ± 2.00) centimeter</span>
</pre></div>
</div>
<p>Mathematical operations with Measurements, return new measurements following the <a class="reference external" href="http://en.wikipedia.org/wiki/Propagation_of_uncertainty">Propagation of uncertainty</a> rules.</p>
<div class="highlight-default"><div class="highlight"><pre><span></span><span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="mi">2</span> <span class="o">*</span> <span class="n">book_length</span><span class="p">)</span>
<span class="go">(40.0 +/- 4.0) centimeter</span>
<span class="gp">>>> </span><span class="n">width</span> <span class="o">=</span> <span class="p">(</span><span class="mi">10</span> <span class="o">*</span> <span class="n">ureg</span><span class="o">.</span><span class="n">centimeter</span><span class="p">)</span><span class="o">.</span><span class="n">plus_minus</span><span class="p">(</span><span class="mi">1</span><span class="p">)</span>
<span class="gp">>>> </span><span class="nb">print</span><span class="p">(</span><span class="s1">'</span><span class="si">{:.02f}</span><span class="s1">'</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">book_length</span> <span class="o">+</span> <span class="n">width</span><span class="p">))</span>
<span class="go">(30.00 +/- 2.24) centimeter</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">only linear combinations are currently supported.</p>
</div>
</div>
</div>
</div>
</div>
<div class="sphinxsidebar" role="navigation" aria-label="main navigation">
<div class="sphinxsidebarwrapper"><p><a href="index.html">
<img src="_images/logo-full.jpg" alt="Logo" style="width:80%;height:80%"/>
</a></p>
<h3>About Pint</h3>
Units in Python.
You are currently looking at the documentation of version 0.7.2.
<h3>Other Formats</h3>
<p>
You can download the documentation in other formats as well:
</p>
<ul>
<li><a href="https://media.readthedocs.org/pdf/pint/latest/pint.pdf">as PDF</a>
<li><a href="https://media.readthedocs.org/htmlzip/pint/latest/pint.zip">as zipped HTML</a>
<li><a href="https://media.readthedocs.org/epub/pint/latest/pint.epub">as ePub</a>
</ul>
<h3>Useful Links</h3>
<ul>
<li><a href="https://pypi.python.org/pypi/Pint/">Pint @ PyPI</a></li>
<li><a href="https://github.com/hgrecco/pint">Code in GitHub</a></li>
<li><a href="https://github.com/hgrecco/pint/issues">Issue Tracker</a></li>
</ul>
<h3>Related Topics</h3>
<ul>
<li><a href="index.html">Documentation overview</a></li>
<p>
<b>Previous</b><br/>
<a href="contexts.html" title="previous chapter">Contexts</a>
</p>
<p>
<b>Next</b><br/>
<a href="defining.html" title="next chapter">Defining units</a>
</p>
<div role="note" aria-label="source link">
<h3>This Page</h3>
<ul class="this-page-menu">
<li><a href="_sources/measurement.txt"
rel="nofollow">Show Source</a></li>
</ul>
</div>
<div id="searchbox" style="display: none" role="search">
<h3>Quick search</h3>
<form class="search" action="search.html" method="get">
<div><input type="text" name="q" /></div>
<div><input type="submit" value="Go" /></div>
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form>
</div>
<script type="text/javascript">$('#searchbox').show(0);</script>
</div>
</div>
<div class="clearer"></div>
</div>
<a href="http://github.com/hgrecco/pint"><img style="position: fixed; top: 0; right: 0; border: 0;"
src="" alt="Fork me on GitHub" /></a>
<div class="footer">
© Copyright 2016, Hernan E. Grecco. Pint 0.7.2.
Created using <a href="http://sphinx.pocoo.org/">Sphinx</a>.
</div>
</body>
</html>
|