fibre.xmds

XMDS is a code generator that integrates equations. You write them down in human readable form in a

<?xml version="1.0"?>
<!--Example fibre noise simulation-->

<!-- $Id: fibre.xmds,v 1.13 2004/07/14 06:37:05 joehope Exp $ -->

<!--  Copyright (C) 2000-2004                                           -->
<!--                                                                    -->
<!--  Code contributed by Greg Collecutt, Joseph Hope and Paul Cochrane -->
<!--                                                                    -->
<!--  This file is part of xmds.                                        -->
<!--                                                                    -->
<!--  This program is free software; you can redistribute it and/or     -->
<!--  modify it under the terms of the GNU General Public License       -->
<!--  as published by the Free Software Foundation; either version 2    -->
<!--  of the License, or (at your option) any later version.            -->
<!--                                                                    -->
<!--  This program is distributed in the hope that it will be useful,   -->
<!--  but WITHOUT ANY WARRANTY; without even the implied warranty of    -->
<!--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the     -->
<!--  GNU General Public License for more details.                      -->
<!--                                                                    -->
<!--  You should have received a copy of the GNU General Public License -->
<!--  along with this program; if not, write to the Free Software       -->
<!--  Foundation, Inc., 59 Temple Place - Suite 330, Boston,            -->
<!--  MA  02111-1307, USA.                                              -->

<simulation>

  <!-- Global system parameters and functionality -->
  <name>fibre</name>

  <author> Unknown Author </author>
  <description>
    Example fibre noise simulation
  </description>

  <prop_dim>t</prop_dim>
  <error_check>no</error_check>
  <stochastic>yes</stochastic>
  <use_mpi>no</use_mpi>
  <paths>1</paths>
  <seed>1 2</seed>
  <noises>2</noises>
  <benchmark>yes</benchmark>

  <use_wisdom>yes</use_wisdom>

  <!-- Global variables for the simulation -->
  <globals>
  <![CDATA[
    const double ggamma = 1;
    const double beta = sqrt(2.0*2.0*M_PI*ggamma/10.0);
  ]]>
  </globals>

  <!-- Field to be integrated over -->
  <field>
    <name>main</name>
    <dimensions>   x   </dimensions>
    <lattice>     50  </lattice>
    <domains>  (-5,5)  </domains>
    <samples>1</samples>

    <vector>
      <name>main</name>
      <type>complex</type>
      <components>phi</components>
      <fourier_space>no</fourier_space>
      <![CDATA[
        phi=0;
      ]]>
    </vector>
  </field>

  <!-- The sequence of integrations to perform -->
  <sequence>
    <integrate>
      <algorithm>SIIP</algorithm>
      <interval>2.5</interval>
      <lattice>5000</lattice>
      <samples>50</samples>
      <k_operators>
        <constant>yes</constant>
        <operator_names>L</operator_names>
	<![CDATA[
	  L = i*(-kx*kx);
	]]>
      </k_operators>
      <iterations>3</iterations>
      <![CDATA[
        dphi_dt = L[phi] - ggamma*phi + beta/sqrt(2.0)*complex(n_1,n_2);
      ]]>
    </integrate>
  </sequence>

  <!-- The output to generate -->
  <output format="ascii" precision="double">
    <group>
      <sampling>
      <fourier_space> yes </fourier_space>
      <lattice>       50  </lattice>
      <moments>pow_dens</moments>
      <![CDATA[
        pow_dens = conj(phi)*phi;
      ]]>
      </sampling>
    </group>
  </output>
</simulation>