Merge branch 'master' of https://github.com/weslowrie/pyclaw into pyclaw_openmp

Update again.

Author: weslowrie

examples/euler_1d/shocktube.py

@@ -0,0 +1,110 @@
+#!/usr/bin/env python
+# encoding: utf-8
+r"""
+Shock-tube problem
+===================================
+
+Solve the one-dimensional Euler equations for inviscid, compressible flow:
+
+.. math::
+    \rho_t + (\rho u)_x & = 0 \\
+    (\rho u)_t + (\rho u^2 + p)_x & = 0 \\
+    E_t + (u (E + p) )_x & = 0.
+
+The fluid is an ideal gas, with pressure given by :math:`p=\rho (\gamma-1)e` where
+e is internal energy.
+
+This script runs a shock-tube problem.
+"""
+from clawpack import riemann
+from clawpack.riemann.euler_with_efix_1D_constants import *
+
+gamma = 1.4 # Ratio of specific heats
+
+def setup(use_petsc=False, outdir='./_output', solver_type='classic',
+          kernel_language='Python',disable_output=False):
+
+    if use_petsc:
+        import clawpack.petclaw as pyclaw
+    else:
+        from clawpack import pyclaw
+
+    if kernel_language =='Python':
+        rs = riemann.euler_1D_py.euler_hllc_1D
+    elif kernel_language =='Fortran':
+        rs = riemann.euler_with_efix_1D
+
+    if solver_type=='sharpclaw':
+        solver = pyclaw.SharpClawSolver1D(rs)
+    elif solver_type=='classic':
+        solver = pyclaw.ClawSolver1D(rs)
+
+    solver.kernel_language = kernel_language
+
+    solver.bc_lower[0]=pyclaw.BC.extrap
+    solver.bc_upper[0]=pyclaw.BC.extrap
+
+    mx = 800;
+    x = pyclaw.Dimension(-1.0,1.0,mx,name='x')
+    domain = pyclaw.Domain([x])
+    state = pyclaw.State(domain,num_eqn)
+
+    state.problem_data['gamma'] = gamma
+    state.problem_data['gamma1'] = gamma - 1.
+
+    x = state.grid.x.centers
+
+    rho_l = 1.; rho_r = 1./8
+    p_l = 1.; p_r = 0.1
+    state.q[density ,:] = (x<0.)*rho_l + (x>=0.)*rho_r
+    state.q[momentum,:] = 0.
+    velocity = state.q[momentum,:]/state.q[density,:]
+    pressure = (x<0.)*p_l + (x>=0.)*p_r
+    state.q[energy  ,:] = pressure/(gamma - 1.) + 0.5 * state.q[density,:] * velocity**2
+
+    claw = pyclaw.Controller()
+    claw.tfinal = 0.4
+    claw.solution = pyclaw.Solution(state,domain)
+    claw.solver = solver
+    claw.num_output_times = 10
+    claw.outdir = outdir
+    claw.setplot = setplot
+    claw.keep_copy = True
+    if disable_output:
+        claw.output_format = None
+
+    return claw
+
+#--------------------------
+def setplot(plotdata):
+#--------------------------
+    """ 
+    Specify what is to be plotted at each frame.
+    Input:  plotdata, an instance of visclaw.data.ClawPlotData.
+    Output: a modified version of plotdata.
+    """ 
+    plotdata.clearfigures()  # clear any old figures,axes,items data
+
+    plotfigure = plotdata.new_plotfigure(name='', figno=0)
+
+    plotaxes = plotfigure.new_plotaxes()
+    plotaxes.axescmd = 'subplot(211)'
+    plotaxes.title = 'Density'
+
+    plotitem = plotaxes.new_plotitem(plot_type='1d')
+    plotitem.plot_var = density
+    plotitem.kwargs = {'linewidth':3}
+    
+    plotaxes = plotfigure.new_plotaxes()
+    plotaxes.axescmd = 'subplot(212)'
+    plotaxes.title = 'Energy'
+
+    plotitem = plotaxes.new_plotitem(plot_type='1d')
+    plotitem.plot_var = energy
+    plotitem.kwargs = {'linewidth':3}
+    
+    return plotdata
+
+if __name__=="__main__":
+    from clawpack.pyclaw.util import run_app_from_main
+    output = run_app_from_main(setup,setplot)