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#!/usr/bin/env python3
# ----------------------------------------------------------------
# Programmer(s): Daniel R. Reynolds @ SMU
# ----------------------------------------------------------------
# SUNDIALS Copyright Start
# Copyright (c) 2002-2019, Lawrence Livermore National Security
# and Southern Methodist University.
# All rights reserved.
#
# See the top-level LICENSE and NOTICE files for details.
#
# SPDX-License-Identifier: BSD-3-Clause
# SUNDIALS Copyright End
# ----------------------------------------------------------------
# matplotlib-based plotting script for heat2D.cpp example
# ----------------------------------------------------------------
# imports
import sys
import numpy as np
from pylab import *
from mpl_toolkits.mplot3d import Axes3D
from matplotlib import cm
import matplotlib.pyplot as plt
# determine the number of MPI processes used
nprocs=1
for i in range(1000):
sname = 'heat2d_subdomain.' + repr(i).zfill(3) + '.txt'
try:
f = open(sname,'r')
f.close()
except IOError:
nprocs = i
break
# load subdomain information, store in table
subdomains = np.zeros((nprocs,4), dtype=np.int)
for i in range(nprocs):
sname = 'heat2d_subdomain.' + repr(i).zfill(3) + '.txt'
subd = np.loadtxt(sname, dtype=np.int)
if (i == 0):
nx = subd[0]
ny = subd[1]
else:
if ((subd[0] != nx) or (subd[1] != ny)):
sys.exit("error: subdomain files incompatible (clean up and re-run test)")
subdomains[i,:] = subd[2:6]
# load first processor's data, and determine total number of time steps
data = np.loadtxt('heat2d.000.txt', dtype=np.double)
nt = np.shape(data)[0]
# create empty array for all solution data
results = np.zeros((nt,ny,nx))
# insert first processor's data into results array
istart = subdomains[0,0]
iend = subdomains[0,1]
jstart = subdomains[0,2]
jend = subdomains[0,3]
nxl = iend-istart+1
nyl = jend-jstart+1
for i in range(nt):
results[i,jstart:jend+1,istart:iend+1] = np.reshape(data[i,:], (nyl,nxl))
# iterate over remaining data files, inserting into output
if (nprocs > 1):
for isub in range(1,nprocs):
data = np.loadtxt('heat2d.' + repr(isub).zfill(3) + '.txt', dtype=np.double)
# check that subdomain has correct number of time steps
if (np.shape(data)[0] != nt):
sys.exit('error: subdomain ' + isub + ' has an incorrect number of time steps')
istart = subdomains[isub,0]
iend = subdomains[isub,1]
jstart = subdomains[isub,2]
jend = subdomains[isub,3]
nxl = iend-istart+1
nyl = jend-jstart+1
for i in range(nt):
results[i,jstart:jend+1,istart:iend+1] = np.reshape(data[i,:], (nyl,nxl))
# determine extents of plots
maxtemp = 1.1*results.max()
mintemp = 0.9*results.min()
# generate plots of results
kx = 0.5
ky = 0.75
kprod = (kx+4.0*ky)*np.pi**2
dt = 0.015
for tstep in range(nt):
# set string constants for output plots, current time, mesh size
pname = 'heat2d_surf.' + repr(tstep).zfill(3) + '.png'
cname = 'heat2d_err.' + repr(tstep).zfill(3) + '.png'
tstr = repr(tstep)
nxstr = repr(nx)
nystr = repr(ny)
# set x and y meshgrid objects
xspan = np.linspace(0.0, 1.0, nx)
yspan = np.linspace(0.0, 1.0, ny)
X,Y = np.meshgrid(xspan,yspan)
# plot current solution as a surface, and save to disk
fig = plt.figure(1)
ax = fig.add_subplot(111, projection='3d')
ax.plot_surface(X, Y, results[tstep,:,:], rstride=1, cstride=1,
cmap=cm.jet, linewidth=0, antialiased=True, shade=True)
ax.set_xlabel('x')
ax.set_ylabel('y')
ax.set_zlim((mintemp, maxtemp))
ax.view_init(20,45)
title('u(x,y) at output ' + tstr + ', mesh = ' + nxstr + 'x' + nystr)
savefig(pname)
plt.close()
# plot error in current solution (as a contour, and save to disk)
t = tstep*dt;
at = (1.0 - np.exp(-t*kprod))/kprod
utrue = at*np.sin(np.pi*X)*np.sin(2.0*np.pi*Y);
uerr = np.abs(utrue - results[tstep,:,:])
plt.contourf(xspan,yspan,uerr,15, cmap=plt.cm.jet)
plt.colorbar()
plt.xlabel('x')
plt.ylabel('y')
plt.title('Error at output ' + tstr + ', mesh = ' + nxstr + 'x' + nystr)
plt.savefig(cname)
plt.close()
##### end of script #####
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