Google Git
Sign in
apache / mxnet-test / refs/heads/asf-site / . / versions / master / tutorials / scala / mnist.html
blob: 41302fe3a55d201f05c5c1b6dff4d413825825de [file] [log] [blame]
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8"/>
<meta content="IE=edge" http-equiv="X-UA-Compatible"/>
<meta content="width=device-width, initial-scale=1" name="viewport"/>
<title>Handwritten Digit Recognition — mxnet documentation</title>
<link crossorigin="anonymous" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" rel="stylesheet"/>
<link href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css" rel="stylesheet"/>
<link href="../../_static/basic.css" rel="stylesheet" type="text/css">
<link href="../../_static/pygments.css" rel="stylesheet" type="text/css">
<link href="../../_static/mxnet.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript">
var DOCUMENTATION_OPTIONS = {
URL_ROOT: '../../',
VERSION: '',
COLLAPSE_INDEX: false,
FILE_SUFFIX: '.html',
HAS_SOURCE: true,
SOURCELINK_SUFFIX: ''
};
</script>
<script src="../../_static/jquery-1.11.1.js" type="text/javascript"></script>
<script src="../../_static/underscore.js" type="text/javascript"></script>
<script src="../../_static/searchtools_custom.js" type="text/javascript"></script>
<script src="../../_static/doctools.js" type="text/javascript"></script>
<script src="../../_static/selectlang.js" type="text/javascript"></script>
<script src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML" type="text/javascript"></script>
<script type="text/javascript"> jQuery(function() { Search.loadIndex("/searchindex.js"); Search.init();}); </script>
<script>
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new
Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','https://www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-96378503-1', 'auto');
ga('send', 'pageview');
</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> -->
<!-- -->
<!-- <script type="text/javascript" src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script> -->
<!-- -->
<link href="https://raw.githubusercontent.com/dmlc/web-data/master/mxnet/image/mxnet-icon.png" rel="icon" type="image/png"/>
</link></link></head>
<body role="document"><!-- Previous Navbar Layout
<div class="navbar navbar-default navbar-fixed-top">
<div class="container">
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
<span class="sr-only">Toggle navigation</span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
<span class="icon-bar"></span>
</button>
<a href="../../" class="navbar-brand">
<img src="http://data.mxnet.io/theme/mxnet.png">
</a>
</div>
<div id="navbar" class="navbar-collapse collapse">
<ul id="navbar" class="navbar navbar-left">
<li> <a href="../../get_started/index.html">Get Started</a> </li>
<li> <a href="../../tutorials/index.html">Tutorials</a> </li>
<li> <a href="../../how_to/index.html">How To</a> </li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true">Packages <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="../../packages/python/index.html">
Python
</a></li>
<li><a href="../../packages/r/index.html">
R
</a></li>
<li><a href="../../packages/julia/index.html">
Julia
</a></li>
<li><a href="../../packages/c++/index.html">
C++
</a></li>
<li><a href="../../packages/scala/index.html">
Scala
</a></li>
<li><a href="../../packages/perl/index.html">
Perl
</a></li>
</ul>
</li>
<li> <a href="../../system/index.html">System</a> </li>
<li>
<form class="" role="search" action="../../search.html" method="get" autocomplete="off">
<div class="form-group inner-addon left-addon">
<i class="glyphicon glyphicon-search"></i>
<input type="text" name="q" class="form-control" placeholder="Search">
</div>
<input type="hidden" name="check_keywords" value="yes" />
<input type="hidden" name="area" value="default" />
</form> </li>
</ul>
<ul id="navbar" class="navbar navbar-right">
<li> <a href="../../index.html"><span class="flag-icon flag-icon-us"></span></a> </li>
<li> <a href="../..//zh/index.html"><span class="flag-icon flag-icon-cn"></span></a> </li>
</ul>
</div>
</div>
</div>
Previous Navbar Layout End -->
<div class="navbar navbar-fixed-top">
<div class="container" id="navContainer">
<div class="innder" id="header-inner">
<h1 id="logo-wrap">
<a href="../../" id="logo"><img src="http://data.mxnet.io/theme/mxnet.png"/></a>
</h1>
<nav class="nav-bar" id="main-nav">
<a class="main-nav-link" href="../../get_started/install.html">Install</a>
<a class="main-nav-link" href="../../tutorials/index.html">Tutorials</a>
<a class="main-nav-link" href="../../how_to/index.html">How To</a>
<span id="dropdown-menu-position-anchor">
<a aria-expanded="true" aria-haspopup="true" class="main-nav-link dropdown-toggle" data-toggle="dropdown" href="#" role="button">API <span class="caret"></span></a>
<ul class="dropdown-menu" id="package-dropdown-menu">
<li><a class="main-nav-link" href="../../api/python/index.html">Python</a></li>
<li><a class="main-nav-link" href="../../api/scala/index.html">Scala</a></li>
<li><a class="main-nav-link" href="../../api/r/index.html">R</a></li>
<li><a class="main-nav-link" href="../../api/julia/index.html">Julia</a></li>
<li><a class="main-nav-link" href="../../api/c++/index.html">C++</a></li>
<li><a class="main-nav-link" href="../../api/perl/index.html">Perl</a></li>
</ul>
</span>
<a class="main-nav-link" href="../../architecture/index.html">Architecture</a>
<!-- <a class="main-nav-link" href="../../community/index.html">Community</a> -->
<a class="main-nav-link" href="https://github.com/dmlc/mxnet">Github</a>
<span id="dropdown-menu-position-anchor-version" style="position: relative"><a href="#" class="main-nav-link dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true">Versions(master)<span class="caret"></span></a><ul id="package-dropdown-menu" class="dropdown-menu"><li><a class="main-nav-link" href=http://mxnet.incubator.apache.org/test/>v0.10.14</a></li><li><a class="main-nav-link" href=http://mxnet.incubator.apache.org/test/versions/0.10/index.html>0.10</a></li><li><a class="main-nav-link" href=http://mxnet.incubator.apache.org/test/versions/master/index.html>master</a></li></ul></span></nav>
<script> function getRootPath(){ return "../../" } </script>
<div class="burgerIcon dropdown">
<a class="dropdown-toggle" data-toggle="dropdown" href="#" role="button">☰</a>
<ul class="dropdown-menu dropdown-menu-right" id="burgerMenu">
<li><a href="../../get_started/install.html">Install</a></li>
<li><a href="../../tutorials/index.html">Tutorials</a></li>
<li><a href="../../how_to/index.html">How To</a></li>
<li class="dropdown-submenu">
<a href="#" tabindex="-1">API</a>
<ul class="dropdown-menu">
<li><a href="../../api/python/index.html" tabindex="-1">Python</a>
</li>
<li><a href="../../api/scala/index.html" tabindex="-1">Scala</a>
</li>
<li><a href="../../api/r/index.html" tabindex="-1">R</a>
</li>
<li><a href="../../api/julia/index.html" tabindex="-1">Julia</a>
</li>
<li><a href="../../api/c++/index.html" tabindex="-1">C++</a>
</li>
<li><a href="../../api/perl/index.html" tabindex="-1">Perl</a>
</li>
</ul>
</li>
<li><a href="../../architecture/index.html">Architecture</a></li>
<li><a class="main-nav-link" href="https://github.com/dmlc/mxnet">Github</a></li>
<li id="dropdown-menu-position-anchor-version-mobile" class="dropdown-submenu" style="position: relative"><a href="#" tabindex="-1">Versions(master)</a><ul class="dropdown-menu"><li><a tabindex="-1" href=http://mxnet.incubator.apache.org/test/>v0.10.14</a></li><li><a tabindex="-1" href=http://mxnet.incubator.apache.org/test/versions/0.10/index.html>0.10</a></li><li><a tabindex="-1" href=http://mxnet.incubator.apache.org/test/versions/master/index.html>master</a></li></ul></li></ul>
</div>
<div class="plusIcon dropdown">
<a class="dropdown-toggle" data-toggle="dropdown" href="#" role="button"><span aria-hidden="true" class="glyphicon glyphicon-plus"></span></a>
<ul class="dropdown-menu dropdown-menu-right" id="plusMenu"></ul>
</div>
<div id="search-input-wrap">
<form action="../../search.html" autocomplete="off" class="" method="get" role="search">
<div class="form-group inner-addon left-addon">
<i class="glyphicon glyphicon-search"></i>
<input class="form-control" name="q" placeholder="Search" type="text"/>
</div>
<input name="check_keywords" type="hidden" value="yes">
<input name="area" type="hidden" value="default"/>
</input></form>
<div id="search-preview"></div>
</div>
<div id="searchIcon">
<span aria-hidden="true" class="glyphicon glyphicon-search"></span>
</div>
<!-- <div id="lang-select-wrap"> -->
<!-- <label id="lang-select-label"> -->
<!-- <\!-- <i class="fa fa-globe"></i> -\-> -->
<!-- <span></span> -->
<!-- </label> -->
<!-- <select id="lang-select"> -->
<!-- <option value="en">Eng</option> -->
<!-- <option value="zh">中文</option> -->
<!-- </select> -->
<!-- </div> -->
<!-- <a id="mobile-nav-toggle">
<span class="mobile-nav-toggle-bar"></span>
<span class="mobile-nav-toggle-bar"></span>
<span class="mobile-nav-toggle-bar"></span>
</a> -->
</div>
</div>
</div>
<div class="container">
<div class="row">
<div aria-label="main navigation" class="sphinxsidebar leftsidebar" role="navigation">
<div class="sphinxsidebarwrapper">
<ul>
<li class="toctree-l1"><a class="reference internal" href="../../api/python/index.html">Python Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/r/index.html">R Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/julia/index.html">Julia Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/c++/index.html">C++ Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/scala/index.html">Scala Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/perl/index.html">Perl Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../how_to/index.html">HowTo Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../architecture/index.html">System Documents</a></li>
<li class="toctree-l1"><a class="reference internal" href="../index.html">Tutorials</a></li>
</ul>
</div>
</div>
<div class="content">
<div class="section" id="handwritten-digit-recognition">
<span id="handwritten-digit-recognition"></span><h1>Handwritten Digit Recognition<a class="headerlink" href="#handwritten-digit-recognition" title="Permalink to this headline"></a></h1>
<p>This Scala tutorial guides you through a classic computer vision application: identifying hand written digits.</p>
<p>Let’s train a 3-layer network (i.e multilayer perceptron network) on the MNIST dataset to classify handwritten digits.</p>
<div class="section" id="define-the-network">
<span id="define-the-network"></span><h2>Define the Network<a class="headerlink" href="#define-the-network" title="Permalink to this headline"></a></h2>
<p>First, define the neural network’s architecture using the Symbol API:</p>
<div class="highlight-scala"><div class="highlight"><pre><span></span><span class="k">import</span> <span class="nn">ml.dmlc.mxnet._</span>
<span class="k">import</span> <span class="nn">ml.dmlc.mxnet.optimizer.SGD</span>
<span class="c1">// model definition</span>
<span class="k">val</span> <span class="n">data</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">Variable</span><span class="o">(</span><span class="s">"data"</span><span class="o">)</span>
<span class="k">val</span> <span class="n">fc1</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">FullyConnected</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"fc1"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">data</span><span class="o">,</span> <span class="s">"num_hidden"</span> <span class="o">-></span> <span class="mi">128</span><span class="o">))</span>
<span class="k">val</span> <span class="n">act1</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">Activation</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"relu1"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">fc1</span><span class="o">,</span> <span class="s">"act_type"</span> <span class="o">-></span> <span class="s">"relu"</span><span class="o">))</span>
<span class="k">val</span> <span class="n">fc2</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">FullyConnected</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"fc2"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">act1</span><span class="o">,</span> <span class="s">"num_hidden"</span> <span class="o">-></span> <span class="mi">64</span><span class="o">))</span>
<span class="k">val</span> <span class="n">act2</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">Activation</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"relu2"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">fc2</span><span class="o">,</span> <span class="s">"act_type"</span> <span class="o">-></span> <span class="s">"relu"</span><span class="o">))</span>
<span class="k">val</span> <span class="n">fc3</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">FullyConnected</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"fc3"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">act2</span><span class="o">,</span> <span class="s">"num_hidden"</span> <span class="o">-></span> <span class="mi">10</span><span class="o">))</span>
<span class="k">val</span> <span class="n">mlp</span> <span class="k">=</span> <span class="nc">Symbol</span><span class="o">.</span><span class="nc">SoftmaxOutput</span><span class="o">(</span><span class="n">name</span> <span class="k">=</span> <span class="s">"sm"</span><span class="o">)()(</span><span class="nc">Map</span><span class="o">(</span><span class="s">"data"</span> <span class="o">-></span> <span class="n">fc3</span><span class="o">))</span>
</pre></div>
</div>
</div>
<div class="section" id="load-the-data">
<span id="load-the-data"></span><h2>Load the Data<a class="headerlink" href="#load-the-data" title="Permalink to this headline"></a></h2>
<p>Then, load the training and validation data using DataIterators.</p>
<p>You can download the MNIST data using the <a class="reference external" href="https://github.com/dmlc/mxnet/blob/master/scala-package/core/scripts/get_mnist_data.sh">get_mnist_data script</a>. We’ve already written a DataIterator for the MNIST dataset:</p>
<div class="highlight-scala"><div class="highlight"><pre><span></span><span class="c1">// load MNIST dataset</span>
<span class="k">val</span> <span class="n">trainDataIter</span> <span class="k">=</span> <span class="nc">IO</span><span class="o">.</span><span class="nc">MNISTIter</span><span class="o">(</span><span class="nc">Map</span><span class="o">(</span>
<span class="s">"image"</span> <span class="o">-></span> <span class="s">"data/train-images-idx3-ubyte"</span><span class="o">,</span>
<span class="s">"label"</span> <span class="o">-></span> <span class="s">"data/train-labels-idx1-ubyte"</span><span class="o">,</span>
<span class="s">"data_shape"</span> <span class="o">-></span> <span class="s">"(1, 28, 28)"</span><span class="o">,</span>
<span class="s">"label_name"</span> <span class="o">-></span> <span class="s">"sm_label"</span><span class="o">,</span>
<span class="s">"batch_size"</span> <span class="o">-></span> <span class="s">"50"</span><span class="o">,</span>
<span class="s">"shuffle"</span> <span class="o">-></span> <span class="s">"1"</span><span class="o">,</span>
<span class="s">"flat"</span> <span class="o">-></span> <span class="s">"0"</span><span class="o">,</span>
<span class="s">"silent"</span> <span class="o">-></span> <span class="s">"0"</span><span class="o">,</span>
<span class="s">"seed"</span> <span class="o">-></span> <span class="s">"10"</span><span class="o">))</span>
<span class="k">val</span> <span class="n">valDataIter</span> <span class="k">=</span> <span class="nc">IO</span><span class="o">.</span><span class="nc">MNISTIter</span><span class="o">(</span><span class="nc">Map</span><span class="o">(</span>
<span class="s">"image"</span> <span class="o">-></span> <span class="s">"data/t10k-images-idx3-ubyte"</span><span class="o">,</span>
<span class="s">"label"</span> <span class="o">-></span> <span class="s">"data/t10k-labels-idx1-ubyte"</span><span class="o">,</span>
<span class="s">"data_shape"</span> <span class="o">-></span> <span class="s">"(1, 28, 28)"</span><span class="o">,</span>
<span class="s">"label_name"</span> <span class="o">-></span> <span class="s">"sm_label"</span><span class="o">,</span>
<span class="s">"batch_size"</span> <span class="o">-></span> <span class="s">"50"</span><span class="o">,</span>
<span class="s">"shuffle"</span> <span class="o">-></span> <span class="s">"1"</span><span class="o">,</span>
<span class="s">"flat"</span> <span class="o">-></span> <span class="s">"0"</span><span class="o">,</span> <span class="s">"silent"</span> <span class="o">-></span> <span class="s">"0"</span><span class="o">))</span>
</pre></div>
</div>
</div>
<div class="section" id="train-the-model">
<span id="train-the-model"></span><h2>Train the model<a class="headerlink" href="#train-the-model" title="Permalink to this headline"></a></h2>
<p>We can use the FeedForward builder to train our network:</p>
<div class="highlight-scala"><div class="highlight"><pre><span></span><span class="c1">// setup model and fit the training data</span>
<span class="k">val</span> <span class="n">model</span> <span class="k">=</span> <span class="nc">FeedForward</span><span class="o">.</span><span class="n">newBuilder</span><span class="o">(</span><span class="n">mlp</span><span class="o">)</span>
<span class="o">.</span><span class="n">setContext</span><span class="o">(</span><span class="nc">Context</span><span class="o">.</span><span class="n">cpu</span><span class="o">())</span>
<span class="o">.</span><span class="n">setNumEpoch</span><span class="o">(</span><span class="mi">10</span><span class="o">)</span>
<span class="o">.</span><span class="n">setOptimizer</span><span class="o">(</span><span class="k">new</span> <span class="nc">SGD</span><span class="o">(</span><span class="n">learningRate</span> <span class="k">=</span> <span class="mf">0.1f</span><span class="o">,</span> <span class="n">momentum</span> <span class="k">=</span> <span class="mf">0.9f</span><span class="o">,</span> <span class="n">wd</span> <span class="k">=</span> <span class="mf">0.0001f</span><span class="o">))</span>
<span class="o">.</span><span class="n">setTrainData</span><span class="o">(</span><span class="n">trainDataIter</span><span class="o">)</span>
<span class="o">.</span><span class="n">setEvalData</span><span class="o">(</span><span class="n">valDataIter</span><span class="o">)</span>
<span class="o">.</span><span class="n">build</span><span class="o">()</span>
</pre></div>
</div>
</div>
<div class="section" id="make-predictions">
<span id="make-predictions"></span><h2>Make predictions<a class="headerlink" href="#make-predictions" title="Permalink to this headline"></a></h2>
<p>Finally, let’s make predictions against the validation dataset and compare the predicted labels with the real labels.</p>
<div class="highlight-scala"><div class="highlight"><pre><span></span><span class="k">val</span> <span class="n">probArrays</span> <span class="k">=</span> <span class="n">model</span><span class="o">.</span><span class="n">predict</span><span class="o">(</span><span class="n">valDataIter</span><span class="o">)</span>
<span class="c1">// in this case, we do not have multiple outputs</span>
<span class="n">require</span><span class="o">(</span><span class="n">probArrays</span><span class="o">.</span><span class="n">length</span> <span class="o">==</span> <span class="mi">1</span><span class="o">)</span>
<span class="k">val</span> <span class="n">prob</span> <span class="k">=</span> <span class="n">probArrays</span><span class="o">(</span><span class="mi">0</span><span class="o">)</span>
<span class="c1">// get real labels</span>
<span class="k">import</span> <span class="nn">scala.collection.mutable.ListBuffer</span>
<span class="n">valDataIter</span><span class="o">.</span><span class="n">reset</span><span class="o">()</span>
<span class="k">val</span> <span class="n">labels</span> <span class="k">=</span> <span class="nc">ListBuffer</span><span class="o">.</span><span class="n">empty</span><span class="o">[</span><span class="kt">NDArray</span><span class="o">]</span>
<span class="k">while</span> <span class="o">(</span><span class="n">valDataIter</span><span class="o">.</span><span class="n">hasNext</span><span class="o">)</span> <span class="o">{</span>
<span class="k">val</span> <span class="n">evalData</span> <span class="k">=</span> <span class="n">valDataIter</span><span class="o">.</span><span class="n">next</span><span class="o">()</span>
<span class="n">labels</span> <span class="o">+=</span> <span class="n">evalData</span><span class="o">.</span><span class="n">label</span><span class="o">(</span><span class="mi">0</span><span class="o">).</span><span class="n">copy</span><span class="o">()</span>
<span class="o">}</span>
<span class="k">val</span> <span class="n">y</span> <span class="k">=</span> <span class="nc">NDArray</span><span class="o">.</span><span class="n">concatenate</span><span class="o">(</span><span class="n">labels</span><span class="o">)</span>
<span class="c1">// get predicted labels</span>
<span class="k">val</span> <span class="n">predictedY</span> <span class="k">=</span> <span class="nc">NDArray</span><span class="o">.</span><span class="n">argmaxChannel</span><span class="o">(</span><span class="n">prob</span><span class="o">)</span>
<span class="n">require</span><span class="o">(</span><span class="n">y</span><span class="o">.</span><span class="n">shape</span> <span class="o">==</span> <span class="n">predictedY</span><span class="o">.</span><span class="n">shape</span><span class="o">)</span>
<span class="c1">// calculate accuracy</span>
<span class="k">var</span> <span class="n">numCorrect</span> <span class="k">=</span> <span class="mi">0</span>
<span class="k">var</span> <span class="n">numTotal</span> <span class="k">=</span> <span class="mi">0</span>
<span class="k">for</span> <span class="o">((</span><span class="n">labelElem</span><span class="o">,</span> <span class="n">predElem</span><span class="o">)</span> <span class="k"><-</span> <span class="n">y</span><span class="o">.</span><span class="n">toArray</span> <span class="n">zip</span> <span class="n">predictedY</span><span class="o">.</span><span class="n">toArray</span><span class="o">)</span> <span class="o">{</span>
<span class="k">if</span> <span class="o">(</span><span class="n">labelElem</span> <span class="o">==</span> <span class="n">predElem</span><span class="o">)</span> <span class="o">{</span>
<span class="n">numCorrect</span> <span class="o">+=</span> <span class="mi">1</span>
<span class="o">}</span>
<span class="n">numTotal</span> <span class="o">+=</span> <span class="mi">1</span>
<span class="o">}</span>
<span class="k">val</span> <span class="n">acc</span> <span class="k">=</span> <span class="n">numCorrect</span><span class="o">.</span><span class="n">toFloat</span> <span class="o">/</span> <span class="n">numTotal</span>
<span class="n">println</span><span class="o">(</span><span class="s">s"Final accuracy = </span><span class="si">$acc</span><span class="s">"</span><span class="o">)</span>
</pre></div>
</div>
<p>Check out more MXNet Scala examples below.</p>
</div>
<div class="section" id="next-steps">
<span id="next-steps"></span><h2>Next Steps<a class="headerlink" href="#next-steps" title="Permalink to this headline"></a></h2>
<div class="toctree-wrapper compound">
<ul>
<li class="toctree-l1"><a class="reference external" href="http://mxnet.io/api/scala/">Scala API</a></li>
<li class="toctree-l1"><a class="reference external" href="https://github.com/dmlc/mxnet/tree/master/scala-package/examples/">More Scala Examples</a></li>
<li class="toctree-l1"><a class="reference external" href="http://mxnet.io/tutorials/index.html">MXNet tutorials index</a></li>
</ul>
</div>
</div>
</div>
<div class="container">
<div class="footer">
<p> © 2015-2017 DMLC. All rights reserved. </p>
</div>
</div>
</div>
<div aria-label="main navigation" class="sphinxsidebar rightsidebar" role="navigation">
<div class="sphinxsidebarwrapper">
<h3><a href="../../index.html">Table Of Contents</a></h3>
<ul>
<li><a class="reference internal" href="#">Handwritten Digit Recognition</a><ul>
<li><a class="reference internal" href="#define-the-network">Define the Network</a></li>
<li><a class="reference internal" href="#load-the-data">Load the Data</a></li>
<li><a class="reference internal" href="#train-the-model">Train the model</a></li>
<li><a class="reference internal" href="#make-predictions">Make predictions</a></li>
<li><a class="reference internal" href="#next-steps">Next Steps</a></li>
</ul>
</li>
</ul>
</div>
</div>
</div> <!-- pagename != index -->
<script crossorigin="anonymous" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<script src="../../_static/js/sidebar.js" type="text/javascript"></script>
<script src="../../_static/js/search.js" type="text/javascript"></script>
<script src="../../_static/js/navbar.js" type="text/javascript"></script>
<script src="../../_static/js/clipboard.min.js" type="text/javascript"></script>
<script src="../../_static/js/copycode.js" type="text/javascript"></script>
<script type="text/javascript">
$('body').ready(function () {
$('body').css('visibility', 'visible');
});
</script>
</div></body>
</html>