1 | """Example of shallow water wave equation. |
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2 | |
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3 | This script sets up a 2D version of the 1D LWRU1 benchmark with initial condition stated in the file benchmark_1.txt. |
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4 | |
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5 | See also |
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6 | |
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7 | http://www.cee.cornell.edu/longwave/index.cfm?page=benchmark&problem=1 |
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8 | |
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9 | |
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10 | """ |
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11 | |
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12 | ###################### |
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13 | # Module imports |
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14 | |
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15 | from anuga.pyvolution.shallow_water import Domain, Reflective_boundary,\ |
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16 | Dirichlet_boundary,Transmissive_boundary, Constant_height, Constant_stage |
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17 | |
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18 | from anuga.pyvolution.mesh_factory import rectangular_cross |
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19 | from Numeric import array, zeros, Float, allclose |
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20 | |
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21 | |
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22 | ####################### |
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23 | # Domain |
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24 | # |
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25 | |
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26 | |
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27 | print 'Creating domain' |
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28 | #Create basic mesh |
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29 | # |
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30 | #The initial condition extends 50km off shore |
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31 | #and 5,000m is allowed on shore for wetting |
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32 | #(only about 200m is expected, though) |
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33 | |
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34 | points, vertices, boundary = rectangular_cross(150, 15, |
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35 | len1=55000, len2=5000, |
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36 | origin = (-5000, 0.0)) |
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37 | |
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38 | #points, vertices, boundary = rectangular_cross(100, 10, |
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39 | # len1=55000, len2=5000, |
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40 | # origin = (-5000, 0.0)) |
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41 | |
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42 | |
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43 | #Create shallow water domain |
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44 | domain = Domain(points, vertices, boundary) |
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45 | |
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46 | domain.check_integrity() |
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47 | domain.default_order = 2 |
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48 | |
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49 | #Output params |
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50 | domain.smooth = True |
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51 | domain.reduction = min #Looks a lot better on top of steep slopes |
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52 | print "Number of triangles = ", len(domain) |
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53 | |
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54 | domain.visualise = False |
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55 | domain.store = True #Store for visualisation purposes |
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56 | domain.format = 'sww' #Native netcdf visualisation format |
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57 | |
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58 | import sys, os |
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59 | base = os.path.basename(sys.argv[0]) |
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60 | |
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61 | basename, _ = os.path.splitext(base) |
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62 | domain.set_name(basename) |
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63 | |
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64 | #Set initial values |
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65 | def slope(x, y): |
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66 | return -x/10 |
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67 | |
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68 | |
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69 | class IC_x: |
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70 | """ |
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71 | Read 1D initial condition and provide values at any x, y |
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72 | |
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73 | File is assumed to list x values in the first column and |
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74 | stage in the second. |
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75 | """ |
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76 | |
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77 | def __init__(self, filename): |
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78 | |
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79 | self.x = [] |
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80 | self.w = [] |
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81 | fid = open(filename) |
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82 | for line in fid.readlines(): |
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83 | fields = line.split() |
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84 | assert len(fields) == 2, '%s' %fields |
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85 | self.x.append( float(fields[0]) ) |
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86 | self.w.append( float(fields[1]) ) |
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87 | |
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88 | #print 'X', self.x, len(self.x) |
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89 | #print 'W', self.w, len(self.w) |
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90 | #from pylab import plot, show |
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91 | #plot(self.x, self.w) |
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92 | #show() |
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93 | #import sys; sys.exit() |
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94 | |
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95 | def __call__(self, x, y): |
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96 | |
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97 | w = zeros( len(x), Float ) |
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98 | for i in range(len(x)): |
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99 | xi = x[i] |
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100 | |
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101 | |
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102 | #Find slot |
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103 | |
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104 | if xi < self.x[0]: |
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105 | w[i] = self.w[0] |
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106 | elif xi > self.x[-1]: |
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107 | w[i] = self.w[-1] |
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108 | else: |
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109 | index = 0 |
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110 | while xi > self.x[index]: index += 1 |
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111 | while xi < self.x[index]: index -= 1 |
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112 | |
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113 | #print xi, index, self.x[index], self.w[index] |
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114 | |
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115 | if xi == self.x[index]: |
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116 | #if allclose(xi, self.x[index]): |
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117 | #Protect against case where x is the last value |
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118 | # - also works in general when x == self.x[i] |
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119 | ratio = 0 |
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120 | else: |
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121 | #x is now between index and index+1 |
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122 | ratio = (xi - self.x[index])/\ |
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123 | (self.x[index+1] - self.x[index]) |
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124 | |
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125 | #print xi, index, self.x[index], ratio |
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126 | |
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127 | #Compute interpolated value |
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128 | if ratio > 0: |
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129 | w[i] = self.w[index] +\ |
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130 | ratio*(self.w[index+1] - self.w[index]) |
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131 | else: |
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132 | w[i] = self.w[index] |
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133 | |
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134 | #print x, w |
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135 | return w |
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136 | |
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137 | |
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138 | |
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139 | print 'Field values' |
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140 | domain.set_quantity('elevation', slope) |
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141 | domain.set_quantity('friction', 0.0) |
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142 | domain.set_quantity('stage', IC_x('lwru1_IC.txt')) |
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143 | |
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144 | #import sys; sys.exit() |
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145 | |
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146 | #print domain.quantities['stage'].centroid_values |
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147 | |
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148 | ###################### |
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149 | # Boundary conditions |
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150 | # |
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151 | print 'Boundaries' |
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152 | Br = Reflective_boundary(domain) |
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153 | Bt = Transmissive_boundary(domain) |
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154 | |
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155 | #Constant inflow |
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156 | Bd = Dirichlet_boundary([0.0, 0.0, 0.0]) |
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157 | |
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158 | #Set boundary conditions |
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159 | domain.set_boundary({'left': Br, 'right': Br, 'bottom': Br, 'top': Br}) |
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160 | |
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161 | |
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162 | #Evolve |
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163 | import time |
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164 | t0 = time.time() |
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165 | |
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166 | |
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167 | |
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168 | |
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169 | pt = [] |
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170 | xes = [] |
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171 | y = 2500 |
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172 | x0 = -500 |
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173 | step = 5 |
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174 | for i in range(1000): |
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175 | x = x0+i*step |
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176 | xes.append(x) |
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177 | pt.append( [x,y] ) |
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178 | |
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179 | from pylab import * |
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180 | from anuga.pyvolution.least_squares import Interpolation |
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181 | |
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182 | |
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183 | V = domain.get_vertex_coordinates(obj=True) #Why? |
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184 | T = domain.get_triangles(obj=True) |
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185 | |
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186 | |
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187 | I = Interpolation(V, |
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188 | T, |
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189 | point_coordinates = pt, |
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190 | verbose = True) |
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191 | |
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192 | |
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193 | f = domain.quantities['elevation'].vertex_values.flat |
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194 | z = I.interpolate( f ) |
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195 | |
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196 | print 'xxxxx' |
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197 | |
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198 | |
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199 | f = domain.quantities['stage'].vertex_values.flat |
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200 | y = I.interpolate( f ) |
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201 | |
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202 | #ion() |
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203 | #plot(xes, y, '-b', xes, z, '-k', [-500, 50000], [0.0, 0.0], '-k') |
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204 | ion() |
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205 | clf() |
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206 | hold(True) |
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207 | plot(xes, y, '-b') |
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208 | plot(xes, z, '-k') |
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209 | plot([-500, 50000], [0.0, 0.0], '-k') |
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210 | set( gca(), Ylim=(-100,100) ) |
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211 | set( gca(), Xlim=(-500,2000) ) |
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212 | draw() |
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213 | ioff() |
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214 | |
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215 | #raw_input('go') |
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216 | for t in domain.evolve(yieldstep = 10, finaltime = 300.0): |
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217 | domain.write_time() |
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218 | |
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219 | |
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220 | f = domain.quantities['stage'].vertex_values.flat |
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221 | y = I.interpolate( f ) |
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222 | |
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223 | clf() |
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224 | hold(True) |
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225 | plot(xes, y, '-b') |
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226 | plot(xes, z, '-k') |
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227 | plot([-500, 50000], [0.0, 0.0], '-k') |
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228 | set( gca(), Ylim=(-100,100) ) |
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229 | set( gca(), Xlim=(-500,2000) ) |
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230 | draw() |
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231 | |
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232 | |
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233 | #raw_input('go') |
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234 | |
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235 | #print y[:], y.shape |
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236 | |
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237 | |
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238 | |
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239 | |
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240 | |
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241 | print 'That took %.2f seconds' %(time.time()-t0) |
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242 | show() |
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