Skip to content

P
Paddle

BaiXuePrincess / Paddle
与 Fork 源项目一致

Fork自 PaddlePaddle / Paddle

通知 1
Star 1
Fork 0
P
Paddle
切换分支/标签
查找文件 普通视图历史永久链接Permalink
rnn.html 25.1 KB
Newer Older
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
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 


<!DOCTYPE html>
<!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]-->
<!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]-->
<head>
  <meta charset="utf-8">
  
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  
  <title>RNNOp design &mdash; PaddlePaddle  documentation</title>
  

  
  

  

  
  
    

  

  
  
    <link rel="stylesheet" href="../../_static/css/theme.css" type="text/css" />
  

  
  
        <link rel="index" title="Index"
              href="../../genindex.html"/>
        <link rel="search" title="Search" href="../../search.html"/>
    <link rel="top" title="PaddlePaddle  documentation" href="../../index.html"/> 

  <link rel="stylesheet" href="https://cdn.jsdelivr.net/perfect-scrollbar/0.6.14/css/perfect-scrollbar.min.css" type="text/css" />
  <link rel="stylesheet" href="../../_static/css/override.css" type="text/css" />
  <script>
  var _hmt = _hmt || [];
  (function() {
    var hm = document.createElement("script");
    hm.src = "//hm.baidu.com/hm.js?b9a314ab40d04d805655aab1deee08ba";
    var s = document.getElementsByTagName("script")[0]; 
    s.parentNode.insertBefore(hm, s);
  })();
  </script>

  

  
  <script src="../../_static/js/modernizr.min.js"></script>

</head>

<body class="wy-body-for-nav" role="document">

  
  <header class="site-header">
    <div class="site-logo">
      <a href="/"><img src="../../_static/images/PP_w.png"></a>
    </div>
    <div class="site-nav-links">
      <div class="site-menu">
        <a class="fork-on-github" href="https://github.com/PaddlePaddle/Paddle" target="_blank"><i class="fa fa-github"></i>Fork me on Github</a>
        <div class="language-switcher dropdown">
          <a type="button" data-toggle="dropdown">
            <span>English</span>
            <i class="fa fa-angle-up"></i>
            <i class="fa fa-angle-down"></i>
          </a>
          <ul class="dropdown-menu">
            <li><a href="/doc_cn">中文</a></li>
            <li><a href="/doc">English</a></li>
          </ul>
        </div>
        <ul class="site-page-links">
          <li><a href="/">Home</a></li>
        </ul>
      </div>
      <div class="doc-module">
        
        <ul>
<li class="toctree-l1"><a class="reference internal" href="../../getstarted/index_en.html">GET STARTED</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../howto/index_en.html">HOW TO</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/index_en.html">API</a></li>
T
Deploy to GitHub Pages: 664691c89af182de3919fc72a7c875311e03893d  
Travis CI 已提交
87 
<li class="toctree-l1"><a class="reference internal" href="../../mobile/index_en.html">MOBILE</a></li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
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 
</ul>

        
<div role="search">
  <form id="rtd-search-form" class="wy-form" action="../../search.html" method="get">
    <input type="text" name="q" placeholder="Search docs" />
    <input type="hidden" name="check_keywords" value="yes" />
    <input type="hidden" name="area" value="default" />
  </form>
</div>        
      </div>
    </div>
  </header>
  
  <div class="main-content-wrap">

    
    <nav class="doc-menu-vertical" role="navigation">
        
          
          <ul>
<li class="toctree-l1"><a class="reference internal" href="../../getstarted/index_en.html">GET STARTED</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../../getstarted/build_and_install/index_en.html">Install and Build</a><ul>
<li class="toctree-l3"><a class="reference internal" href="../../getstarted/build_and_install/docker_install_en.html">PaddlePaddle in Docker Containers</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../getstarted/build_and_install/build_from_source_en.html">Installing from Sources</a></li>
</ul>
</li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="../../howto/index_en.html">HOW TO</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../../howto/usage/cmd_parameter/index_en.html">Set Command-line Parameters</a><ul>
<li class="toctree-l3"><a class="reference internal" href="../../howto/usage/cmd_parameter/use_case_en.html">Use Case</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../howto/usage/cmd_parameter/arguments_en.html">Argument Outline</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../howto/usage/cmd_parameter/detail_introduction_en.html">Detail Description</a></li>
</ul>
</li>
T
Deploy to GitHub Pages: 63ffe5250a120ff430469b8d000deb2b031c4881  
Travis CI 已提交
124 
<li class="toctree-l2"><a class="reference internal" href="../../howto/usage/cluster/cluster_train_en.html">PaddlePaddle Distributed Training</a></li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
125 126 127 128 
<li class="toctree-l2"><a class="reference internal" href="../../howto/usage/k8s/k8s_en.html">Paddle On Kubernetes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../howto/usage/k8s/k8s_aws_en.html">Distributed PaddlePaddle Training on AWS with Kubernetes</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../howto/dev/build_en.html">Build PaddlePaddle from Source Code and Run Unit Test</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../howto/dev/new_layer_en.html">Write New Layers</a></li>
T
Deploy to GitHub Pages: f122a5da2f27038b48f6ed607e296d762050e920  
Travis CI 已提交
129 
<li class="toctree-l2"><a class="reference internal" href="../../howto/dev/contribute_to_paddle_en.html">Contribute Code</a></li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 
<li class="toctree-l2"><a class="reference internal" href="../../howto/deep_model/rnn/index_en.html">RNN Models</a><ul>
<li class="toctree-l3"><a class="reference internal" href="../../howto/deep_model/rnn/rnn_config_en.html">RNN Configuration</a></li>
</ul>
</li>
<li class="toctree-l2"><a class="reference internal" href="../../howto/optimization/gpu_profiling_en.html">Tune GPU Performance</a></li>
</ul>
</li>
<li class="toctree-l1"><a class="reference internal" href="../../api/index_en.html">API</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../../api/v2/model_configs.html">Model Configuration</a><ul>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/activation.html">Activation</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/layer.html">Layers</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/evaluators.html">Evaluators</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/optimizer.html">Optimizer</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/pooling.html">Pooling</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/networks.html">Networks</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/config/attr.html">Parameter Attribute</a></li>
</ul>
</li>
T
Deploy to GitHub Pages: d4d8f742a3bc4366bf410bc9ff29c0c32666bf60  
Travis CI 已提交
148 149 150 151 152 153 
<li class="toctree-l2"><a class="reference internal" href="../../api/v2/data.html">Data Reader Interface and DataSets</a><ul>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/data/data_reader.html">Data Reader Interface</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/data/image.html">Image Interface</a></li>
<li class="toctree-l3"><a class="reference internal" href="../../api/v2/data/dataset.html">Dataset</a></li>
</ul>
</li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
154 155 156 
<li class="toctree-l2"><a class="reference internal" href="../../api/v2/run_logic.html">Training and Inference</a></li>
</ul>
</li>
T
Deploy to GitHub Pages: 664691c89af182de3919fc72a7c875311e03893d  
Travis CI 已提交
157 158 159 160 161 
<li class="toctree-l1"><a class="reference internal" href="../../mobile/index_en.html">MOBILE</a><ul>
<li class="toctree-l2"><a class="reference internal" href="../../mobile/cross_compiling_for_android_en.html">Build PaddlePaddle for Android</a></li>
<li class="toctree-l2"><a class="reference internal" href="../../mobile/cross_compiling_for_raspberry_en.html">Build PaddlePaddle for Raspberry Pi</a></li>
</ul>
</li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 
</ul>

        
    </nav>
    
    <section class="doc-content-wrap">

      

 







<div role="navigation" aria-label="breadcrumbs navigation">
  <ul class="wy-breadcrumbs">
      
    <li>RNNOp design</li>
  </ul>
</div>
      
      <div class="wy-nav-content" id="doc-content">
        <div class="rst-content">
          <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
           <div itemprop="articleBody">
            
  <div class="section" id="rnnop-design">
<span id="rnnop-design"></span><h1>RNNOp design<a class="headerlink" href="#rnnop-design" title="Permalink to this headline"></a></h1>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
193 
<p>This document describes the RNN (Recurrent Neural Network) operator and how it is implemented in PaddlePaddle. The RNN op requires that all instances in a mini-batch have the same length. We will have a more flexible dynamic RNN operator in the future.</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
194 195 
<div class="section" id="rnn-algorithm-implementation">
<span id="rnn-algorithm-implementation"></span><h2>RNN Algorithm Implementation<a class="headerlink" href="#rnn-algorithm-implementation" title="Permalink to this headline"></a></h2>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
196 
<p align="center">
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
197 198 
<img src="./images/rnn.jpg"/>
</p><p>The above diagram shows an RNN unrolled into a full network.</p>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
199 
<p>There are several important concepts here:</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
200 
<ul class="simple">
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
201 202 203 204 
<li><em>step-net</em>: the sub-graph that runs at each step.</li>
<li><em>memory</em>, $h_t$, the state of the current step.</li>
<li><em>ex-memory</em>, $h_{t-1}$, the state of the previous step.</li>
<li><em>initial memory value</em>, the memory of the first (initial) step.</li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
205 206 207 
</ul>
<div class="section" id="step-scope">
<span id="step-scope"></span><h3>Step-scope<a class="headerlink" href="#step-scope" title="Permalink to this headline"></a></h3>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
208 209 
<p>There could be local variables defined in each step-net.  PaddlePaddle runtime realizes these variables in <em>step-scopes</em> which are created for each step.</p>
<p align="center">
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
210 
<img src="./images/rnn.png"/><br/>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
211 212 
Figure 2 illustrates the RNN's data flow
</p><p>Please be aware that every step runs the same step-net.  Each step does the following:</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
213 
<ol class="simple">
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
214 215 216 
<li>Creates the step-scope.</li>
<li>Initializes the local variables including step-outputs, in the step-scope.</li>
<li>Runs the step-net, which uses the above mentioned variables.</li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
217 
</ol>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
218 
<p>The RNN operator will compose its output from step outputs in each of the step scopes.</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
219 220 221 
</div>
<div class="section" id="memory-and-ex-memory">
<span id="memory-and-ex-memory"></span><h3>Memory and Ex-memory<a class="headerlink" href="#memory-and-ex-memory" title="Permalink to this headline"></a></h3>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
222 
<p>Let&#8217;s give more details about memory and ex-memory using a simple example:</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
223 224 225 
<p>$$
h_t = U h_{t-1} + W x_t
$$,</p>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
226 227 228 
<p>where $h_t$ and $h_{t-1}$ are the memory and ex-memory (previous memory) of step $t$ respectively.</p>
<p>In the implementation, we can make an ex-memory variable either &#8220;refer to&#8221; the memory variable of the previous step,
or copy the memory value of the previous step to the current ex-memory variable.</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
229 230 231 232 
</div>
<div class="section" id="usage-in-python">
<span id="usage-in-python"></span><h3>Usage in Python<a class="headerlink" href="#usage-in-python" title="Permalink to this headline"></a></h3>
<p>For more information on Block, please refer to the <a class="reference external" href="https://github.com/PaddlePaddle/Paddle/blob/develop/doc/design/block.md">design doc</a>.</p>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
233 
<p>We can define an RNN&#8217;s step-net using a Block:</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
234 235 
<div class="highlight-python"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">paddle</span> <span class="kn">as</span> <span class="nn">pd</span>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
236 
<span class="n">X</span> <span class="o">=</span> <span class="n">some_op</span><span class="p">()</span> <span class="c1"># x is some operator&#39;s output and is a LoDTensor</span>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
237 238 239 240 241 242 243 244 245 246 247 
<span class="n">a</span> <span class="o">=</span> <span class="n">some_op</span><span class="p">()</span>

<span class="c1"># declare parameters</span>
<span class="n">W</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>
<span class="n">U</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>

<span class="n">rnn</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">create_rnn_op</span><span class="p">(</span><span class="n">output_num</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
<span class="k">with</span> <span class="n">rnn</span><span class="o">.</span><span class="n">stepnet</span><span class="p">():</span>
    <span class="n">x</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_input</span><span class="p">(</span><span class="n">X</span><span class="p">)</span>
    <span class="c1"># declare a memory (rnn&#39;s step)</span>
    <span class="n">h</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_memory</span><span class="p">(</span><span class="n">init</span><span class="o">=</span><span class="n">a</span><span class="p">)</span>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
248 
    <span class="c1"># h.pre_state(), the previous memory of rnn</span>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
249 250 251 252 253 254 255 256 257 258 259 
    <span class="n">new_state</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">add_two</span><span class="p">(</span> <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">W</span><span class="p">,</span> <span class="n">x</span><span class="p">)</span> <span class="o">+</span> <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">U</span><span class="p">,</span> <span class="n">h</span><span class="o">.</span><span class="n">pre_state</span><span class="p">()))</span>
    <span class="c1"># update current memory</span>
    <span class="n">h</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">new_state</span><span class="p">)</span>
    <span class="c1"># indicate that h variables in all step scopes should be merged</span>
    <span class="n">rnn</span><span class="o">.</span><span class="n">add_outputs</span><span class="p">(</span><span class="n">h</span><span class="p">)</span>

<span class="n">out</span> <span class="o">=</span> <span class="n">rnn</span><span class="p">()</span>
</pre></div>
</div>
<p>Python API functions in above example:</p>
<ul class="simple">
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
260 261 262 
<li><code class="docutils literal"><span class="pre">rnn.add_input</span></code>: indicates that the parameter is a variable that will be segmented into step-inputs.</li>
<li><code class="docutils literal"><span class="pre">rnn.add_memory</span></code>: creates a variable used as the memory.</li>
<li><code class="docutils literal"><span class="pre">rnn.add_outputs</span></code>: marks the variables that will be concatenated across steps into the RNN output.</li>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
263 264 265 266 267 
</ul>
</div>
<div class="section" id="nested-rnn-and-lodtensor">
<span id="nested-rnn-and-lodtensor"></span><h3>Nested RNN and LoDTensor<a class="headerlink" href="#nested-rnn-and-lodtensor" title="Permalink to this headline"></a></h3>
<p>An RNN whose step-net includes other RNN operators is known as an <em>nested RNN</em>.</p>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
268 269 270 
<p>For example, we could have a 2-level RNN, where the top level corresponds to paragraphs, and the lower level corresponds to sentences. Each step of the higher level RNN also receives an input from the corresponding step of the lower level, and additionally the output from the previous time step at the same level.</p>
<p>The following figure illustrates feeding in text into the lower level, one sentence at a step, and the feeding in step outputs to the top level. The final top level output is about the whole text.</p>
<p align="center">
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
271 272 273 274 275 276 277 278 279 280 281 282 283 284 
<img src="./images/2_level_rnn.png"/>
</p><div class="highlight-python"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">paddle</span> <span class="kn">as</span> <span class="nn">pd</span>

<span class="n">W</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>
<span class="n">U</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>

<span class="n">W0</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>
<span class="n">U0</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>

<span class="c1"># a is output of some op</span>
<span class="n">a</span> <span class="o">=</span> <span class="n">some_op</span><span class="p">()</span>

<span class="c1"># chapter_data is a set of 128-dim word vectors</span>
<span class="c1"># the first level of LoD is sentence</span>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
285 
<span class="c1"># the second level of LoD is a chapter</span>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 
<span class="n">chapter_data</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">Variable</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="bp">None</span><span class="p">,</span> <span class="mi">128</span><span class="p">],</span> <span class="nb">type</span><span class="o">=</span><span class="n">pd</span><span class="o">.</span><span class="n">lod_tensor</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">2</span><span class="p">)</span>

<span class="k">def</span> <span class="nf">lower_level_rnn</span><span class="p">(</span><span class="n">paragraph</span><span class="p">):</span>
    <span class="sd">&#39;&#39;&#39;</span>
<span class="sd">    x: the input</span>
<span class="sd">    &#39;&#39;&#39;</span>
    <span class="n">rnn</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">create_rnn_op</span><span class="p">(</span><span class="n">output_num</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
    <span class="k">with</span> <span class="n">rnn</span><span class="o">.</span><span class="n">stepnet</span><span class="p">():</span>
        <span class="n">sentence</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_input</span><span class="p">(</span><span class="n">paragraph</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">0</span><span class="p">)</span>
        <span class="n">h</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_memory</span><span class="p">(</span><span class="n">shape</span><span class="o">=</span><span class="p">[</span><span class="mi">20</span><span class="p">,</span> <span class="mi">30</span><span class="p">])</span>
        <span class="n">h</span><span class="o">.</span><span class="n">update</span><span class="p">(</span>
            <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">W</span><span class="p">,</span> <span class="n">sentence</span><span class="p">)</span> <span class="o">+</span> <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">U</span><span class="p">,</span> <span class="n">h</span><span class="o">.</span><span class="n">pre_state</span><span class="p">()))</span>
        <span class="c1"># get the last state as sentence&#39;s info</span>
        <span class="n">rnn</span><span class="o">.</span><span class="n">add_outputs</span><span class="p">(</span><span class="n">h</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">rnn</span>

<span class="n">top_level_rnn</span> <span class="o">=</span> <span class="n">pd</span><span class="o">.</span><span class="n">create_rnn_op</span><span class="p">(</span><span class="n">output_num</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
<span class="k">with</span> <span class="n">top_level_rnn</span><span class="o">.</span><span class="n">stepnet</span><span class="p">():</span>
    <span class="n">paragraph_data</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_input</span><span class="p">(</span><span class="n">chapter_data</span><span class="p">,</span> <span class="n">level</span><span class="o">=</span><span class="mi">1</span><span class="p">)</span>
    <span class="n">low_rnn</span> <span class="o">=</span> <span class="n">lower_level_rnn</span><span class="p">(</span><span class="n">paragraph_data</span><span class="p">)</span>
    <span class="n">paragraph_out</span> <span class="o">=</span> <span class="n">low_rnn</span><span class="p">()</span>

    <span class="n">h</span> <span class="o">=</span> <span class="n">rnn</span><span class="o">.</span><span class="n">add_memory</span><span class="p">(</span><span class="n">init</span><span class="o">=</span><span class="n">a</span><span class="p">)</span>
    <span class="n">h</span><span class="o">.</span><span class="n">update</span><span class="p">(</span>
        <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">W0</span><span class="p">,</span> <span class="n">paragraph_data</span><span class="p">)</span> <span class="o">+</span> <span class="n">pd</span><span class="o">.</span><span class="n">matmul</span><span class="p">(</span><span class="n">U0</span><span class="p">,</span> <span class="n">h</span><span class="o">.</span><span class="n">pre_state</span><span class="p">()))</span>
    <span class="n">top_level_rnn</span><span class="o">.</span><span class="n">add_outputs</span><span class="p">(</span><span class="n">h</span><span class="p">)</span>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
313 
<span class="c1"># output the last step</span>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
314 315 316 
<span class="n">chapter_out</span> <span class="o">=</span> <span class="n">top_level_rnn</span><span class="p">(</span><span class="n">output_all_steps</span><span class="o">=</span><span class="bp">False</span><span class="p">)</span>
</pre></div>
</div>
T
Deploy to GitHub Pages: e0e3a8a5bb2a33bf1953c7cebdedcf2ea5869b51  
Travis CI 已提交
317 318 319 
<p>In the above example, the construction of the <code class="docutils literal"><span class="pre">top_level_rnn</span></code> calls  <code class="docutils literal"><span class="pre">lower_level_rnn</span></code>.  The input is an LoD Tensor. The top level RNN segments input text data into paragraphs, and the lower level RNN segments each paragraph into sentences.</p>
<p>By default, the <code class="docutils literal"><span class="pre">RNNOp</span></code> will concatenate the outputs from all the time steps.
If the <code class="docutils literal"><span class="pre">output_all_steps</span></code> is set to False, it will only output the final time step.</p>
T
Deploy to GitHub Pages: b3f6b5a9599c548324dd02e225db6a9e1a3e402e  
Travis CI 已提交
320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 
<p align="center">
<img src="images/rnn_2level_data.png"/>
</p></div>
</div>
</div>


           </div>
          </div>
          <footer>
  

  <hr/>

  <div role="contentinfo">
    <p>
        &copy; Copyright 2016, PaddlePaddle developers.

    </p>
  </div>
  Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/snide/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>. 

</footer>

        </div>
      </div>

    </section>

  </div>
  


  

    <script type="text/javascript">
        var DOCUMENTATION_OPTIONS = {
            URL_ROOT:'../../',
            VERSION:'',
            COLLAPSE_INDEX:false,
            FILE_SUFFIX:'.html',
            HAS_SOURCE:  true,
            SOURCELINK_SUFFIX: ".txt",
        };
    </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://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.0/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
       
  

  
  
    <script type="text/javascript" src="../../_static/js/theme.js"></script>
  
  
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
  <script src="https://cdn.jsdelivr.net/perfect-scrollbar/0.6.14/js/perfect-scrollbar.jquery.min.js"></script>
  <script src="../../_static/js/paddle_doc_init.js"></script> 

</body>
</html>