File: write_restart.html

package info (click to toggle)
liggghts 3.8.0%2Brepack1-9
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 27,292 kB
  • sloc: cpp: 151,239; javascript: 9,132; sh: 910; python: 676; makefile: 456; ansic: 411
file content (329 lines) | stat: -rw-r--r-- 11,157 bytes parent folder | download | duplicates (5)
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
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
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
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329


<!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>write_restart command &mdash; LIGGGHTS v3.X documentation</title>
  

  
  
  
  

  

  
  
    

  

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

  

  
    <link rel="top" title="LIGGGHTS v3.X documentation" href="index.html"/> 

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

</head>

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

   
  <div class="wy-grid-for-nav">

    
    <nav data-toggle="wy-nav-shift" class="wy-nav-side">
      <div class="wy-side-scroll">
        <div class="wy-side-nav-search">
          

          
            <a href="Manual.html" class="icon icon-home"> LIGGGHTS
          

          
          </a>

          
            
            
              <div class="version">
                v3.X
              </div>
            
          

          
<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 class="wy-menu wy-menu-vertical" data-spy="affix" role="navigation" aria-label="main navigation">
          
            
            
              
            
            
              <ul>
<li class="toctree-l1"><a class="reference internal" href="Section_intro.html">1. Introduction</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_start.html">2. Getting Started</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_input_script.html">3. Input Script</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_commands.html">4. Commands</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_gran_models.html">5. Contact models</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_mesh_modules.html">6. Mesh modules</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_packages.html">7. Packages</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_howto.html">8. How-to discussions</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_modify.html">9. Modifying &amp; extending LIGGGHTS(R)-PUBLIC</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_python.html">10. Python interface to LIGGGHTS(R)-PUBLIC</a></li>
<li class="toctree-l1"><a class="reference internal" href="Section_errors.html">11. Errors</a></li>
</ul>

            
          
        </div>
      </div>
    </nav>

    <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap">

      
      <nav class="wy-nav-top" role="navigation" aria-label="top navigation">
        
          <i data-toggle="wy-nav-top" class="fa fa-bars"></i>
          <a href="Manual.html">LIGGGHTS</a>
        
      </nav>


      
      <div class="wy-nav-content">
        <div class="rst-content">
          















<div role="navigation" aria-label="breadcrumbs navigation">

  <ul class="wy-breadcrumbs">
    
      <li><a href="Manual.html">Docs</a> &raquo;</li>
        
      <li>write_restart command</li>
    
    
      <li class="wy-breadcrumbs-aside">
        
            
            <a href="_sources/write_restart.txt" rel="nofollow"> View page source</a>
          
          <a href="http://www.cfdem.com"> Website</a>
          
            <a href="Section_commands.html#comm" rel="nofollow"> Commands</a>
            
          
        
      </li>
    
  </ul>

  
  <hr/>
  
</div>
          <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article">
           <div itemprop="articleBody">
            
  <div class="section" id="write-restart-command">
<span id="index-0"></span><h1>write_restart command<a class="headerlink" href="#write-restart-command" title="Permalink to this headline">¶</a></h1>
<div class="section" id="syntax">
<h2>Syntax<a class="headerlink" href="#syntax" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre>write_restart file keyword value ...
</pre></div>
</div>
<ul class="simple">
<li>file = name of file to write restart information to</li>
<li>zero or more keyword/value pairs may be appended</li>
<li>keyword = <em>fileper</em> or <em>nfile</em></li>
</ul>
<pre class="literal-block">
<em>fileper</em> arg = Np
  Np = write one file for every this many processors
<em>nfile</em> arg = Nf
  Nf = write this many files, one from each of Nf processors
</pre>
</div>
<div class="section" id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Permalink to this headline">¶</a></h2>
<div class="highlight-python"><div class="highlight"><pre>write_restart restart.equil
write_restart poly.%.* nfile 10
</pre></div>
</div>
</div>
<div class="section" id="description">
<h2>Description<a class="headerlink" href="#description" title="Permalink to this headline">¶</a></h2>
<p>Write a binary restart file of the current state of the simulation.</p>
<p>During a long simulation, the <a class="reference internal" href="restart.html"><em>restart</em></a> command is
typically used to output restart files periodically.  The
write_restart command is useful after a minimization or whenever you
wish to write out a single current restart file.</p>
<p>Similar to <a class="reference internal" href="dump.html"><em>dump</em></a> files, the restart filename can contain
two wild-card characters.  If a &#8220;*&#8221; appears in the filename, it is
replaced with the current timestep value.  If a &#8220;%&#8221; character appears
in the filename, then one file is written by each processor and the
&#8220;%&#8221; character is replaced with the processor ID from 0 to P-1.  An
additional file with the &#8220;%&#8221; replaced by &#8220;base&#8221; is also written, which
contains global information.  For example, the files written for
filename restart.% would be restart.base, restart.0, restart.1, ...
restart.P-1.  This creates smaller files and can be a fast mode of
output and subsequent input on parallel machines that support parallel
I/O.  The optional <em>fileper</em> and <em>nfile</em> keywords discussed below can
alter the number of files written.</p>
<p>Restart files can be read by a <a class="reference internal" href="read_restart.html"><em>read_restart</em></a>
command to restart a simulation from a particular state.  Because the
file is binary (to enable exact restarts), it may not be readable on
another machine.  In this case, you can use the <span class="xref std std-ref">-r command-line switch</span> to convert a restart file to a data
file.</p>
<div class="admonition warning">
<p class="first admonition-title">Warning</p>
<p class="last">Although the purpose of restart files is to enable
restarting a simulation from where it left off, not all information
about a simulation is stored in the file.  For example, the list of
fixes that were specified during the initial run is not stored, which
means the new input script must specify any fixes you want to use.
Even when restart information is stored in the file, as it is for some
fixes, commands may need to be re-specified in the new input script,
in order to re-use that information.  See the
<a class="reference internal" href="read_restart.html"><em>read_restart</em></a> command for information about what is
stored in a restart file.</p>
</div>
<hr class="docutils" />
<p>The optional <em>nfile</em> or <em>fileper</em> keywords can be used in conjunction
with the &#8220;%&#8221; wildcard character in the specified restart file name.
As explained above, the &#8220;%&#8221; character causes the restart file to be
written in pieces, one piece for each of P processors.  By default P =
the number of processors the simulation is running on.  The <em>nfile</em> or
<em>fileper</em> keyword can be used to set P to a smaller value, which can
be more efficient when running on a large number of processors.</p>
<p>The <em>nfile</em> keyword sets P to the specified Nf value.  For example, if
Nf = 4, and the simulation is running on 100 processors, 4 files will
be written, by processors 0,25,50,75.  Each will collect information
from itself and the next 24 processors and write it to a restart file.</p>
<p>For the <em>fileper</em> keyword, the specified value of Np means write one
file for every Np processors.  For example, if Np = 4, every 4th
processor (0,4,8,12,etc) will collect information from itself and the
next 3 processors and write it to a restart file.</p>
</div>
<hr class="docutils" />
<div class="section" id="restrictions">
<h2>Restrictions<a class="headerlink" href="#restrictions" title="Permalink to this headline">¶</a></h2>
<p>This command requires inter-processor communication to migrate atoms
before the restart file is written.  This means that your system must
be ready to perform a simulation before using this command (force
fields setup, atom masses initialized, etc).</p>
</div>
<div class="section" id="related-commands">
<h2>Related commands<a class="headerlink" href="#related-commands" title="Permalink to this headline">¶</a></h2>
<p><a class="reference internal" href="restart.html"><em>restart</em></a>, <a class="reference internal" href="read_restart.html"><em>read_restart</em></a>,
<a class="reference internal" href="write_data.html"><em>write_data</em></a></p>
<p><strong>Default:</strong> none</p>
</div>
</div>


           </div>
           <div class="articleComments">
            
           </div>
          </div>
          <footer>
  

  <hr/>

  <div role="contentinfo">
    <p>
        &copy; Copyright 2016, DCS Computing GmbH, JKU Linz and Sandia Corporation.

    </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:'v3.X',
            LANGUAGE:'None',
            COLLAPSE_INDEX:false,
            FILE_SUFFIX:'.html',
            HAS_SOURCE:  true,
            SOURCELINK_SUFFIX: ''
        };
    </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="_static/js/theme.js"></script>
  

  
  
  <script type="text/javascript">
      jQuery(function () {
          SphinxRtdTheme.StickyNav.enable();
      });
  </script>
   

</body>
</html>