1 | """Class Quantity - Implements values at each 1d element |
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2 | |
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3 | To create: |
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4 | |
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5 | Quantity(domain, vertex_values) |
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6 | |
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7 | domain: Associated domain structure. Required. |
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8 | |
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9 | vertex_values: N x 2 array of values at each vertex for each element. |
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10 | Default None |
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11 | |
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12 | If vertex_values are None Create array of zeros compatible with domain. |
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13 | Otherwise check that it is compatible with dimenions of domain. |
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14 | Otherwise raise an exception |
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15 | """ |
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16 | |
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17 | |
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18 | class Quantity: |
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19 | |
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20 | def __init__(self, domain, vertex_values=None): |
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21 | |
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22 | #from domain import Domain |
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23 | #from domain_order2 import Domain |
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24 | from domain_t2 import Domain |
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25 | from Numeric import array, zeros, Float |
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26 | |
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27 | msg = 'First argument in Quantity.__init__ ' |
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28 | msg += 'must be of class Domain (or a subclass thereof)' |
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29 | assert isinstance(domain, Domain), msg |
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30 | |
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31 | if vertex_values is None: |
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32 | N = domain.number_of_elements |
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33 | self.vertex_values = zeros((N, 2), Float) |
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34 | else: |
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35 | self.vertex_values = array(vertex_values, Float) |
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36 | |
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37 | N, V = self.vertex_values.shape |
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38 | assert V == 2,\ |
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39 | 'Two vertex values per element must be specified' |
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40 | |
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41 | |
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42 | msg = 'Number of vertex values (%d) must be consistent with'\ |
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43 | %N |
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44 | msg += 'number of elements in specified domain (%d).'\ |
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45 | %domain.number_of_elements |
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46 | |
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47 | assert N == domain.number_of_elements, msg |
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48 | |
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49 | self.domain = domain |
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50 | |
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51 | #Allocate space for other quantities |
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52 | self.centroid_values = zeros(N, Float) |
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53 | #self.edge_values = zeros((N, 2), Float) |
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54 | #edge values are values of the ends of each interval |
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55 | |
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56 | #Intialise centroid values |
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57 | self.interpolate() |
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58 | |
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59 | #Methods for operator overloading |
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60 | def __len__(self): |
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61 | return self.centroid_values.shape[0] |
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62 | |
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63 | def interpolate(self): |
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64 | """Compute interpolated values at centroid |
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65 | Pre-condition: vertex_values have been set |
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66 | """ |
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67 | |
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68 | N = self.vertex_values.shape[0] |
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69 | for i in range(N): |
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70 | v0 = self.vertex_values[i, 0] |
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71 | v1 = self.vertex_values[i, 1] |
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72 | |
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73 | self.centroid_values[i] = (v0 + v1)/2.0 |
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74 | |
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75 | def set_values(self, X, location='vertices'): |
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76 | """Set values for quantity |
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77 | |
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78 | X: Compatible list, Numeric array (see below), constant or function |
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79 | location: Where values are to be stored. |
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80 | Permissible options are: vertices, centroid |
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81 | Default is "vertices" |
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82 | |
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83 | In case of location == 'centroid' the dimension values must |
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84 | be a list of a Numerical array of length N, N being the number |
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85 | of elements in the mesh. Otherwise it must be of dimension Nx3 |
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86 | |
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87 | The values will be stored in elements following their |
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88 | internal ordering. |
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89 | |
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90 | If values are described a function, it will be evaluated at specified points |
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91 | |
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92 | If selected location is vertices, values for centroid and edges |
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93 | will be assigned interpolated values. |
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94 | In any other case, only values for the specified locations |
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95 | will be assigned and the others will be left undefined. |
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96 | """ |
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97 | |
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98 | if location not in ['vertices', 'centroids']:#, 'edges']: |
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99 | msg = 'Invalid location: %s, (possible choices vertices, centroids)' %location |
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100 | raise msg |
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101 | |
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102 | if X is None: |
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103 | msg = 'Given values are None' |
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104 | raise msg |
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105 | |
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106 | import types |
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107 | |
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108 | if callable(X): |
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109 | #Use function specific method |
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110 | self.set_function_values(X, location) |
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111 | elif type(X) in [types.FloatType, types.IntType, types.LongType]: |
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112 | if location == 'centroids': |
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113 | self.centroid_values[:] = X |
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114 | else: |
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115 | self.vertex_values[:] = X |
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116 | |
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117 | else: |
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118 | #Use array specific method |
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119 | self.set_array_values(X, location) |
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120 | |
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121 | if location == 'vertices': |
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122 | #Intialise centroid and edge values |
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123 | self.interpolate() |
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124 | |
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125 | |
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126 | |
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127 | |
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128 | def set_function_values(self, f, location='vertices'): |
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129 | """Set values for quantity using specified function |
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130 | |
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131 | f: x -> z Function where x and z are arrays |
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132 | location: Where values are to be stored. |
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133 | Permissible options are: vertices, centroid |
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134 | Default is "vertices" |
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135 | """ |
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136 | |
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137 | if location == 'centroids': |
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138 | |
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139 | P = self.domain.centroids |
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140 | self.set_values(f(P), location) |
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141 | else: |
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142 | #Vertices |
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143 | P = self.domain.get_vertices() |
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144 | |
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145 | for i in range(2): |
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146 | self.vertex_values[:,i] = f(P[:,i]) |
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147 | |
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148 | def set_array_values(self, values, location='vertices'): |
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149 | """Set values for quantity |
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150 | |
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151 | values: Numeric array |
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152 | location: Where values are to be stored. |
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153 | Permissible options are: vertices, centroid, edges |
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154 | Default is "vertices" |
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155 | |
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156 | In case of location == 'centroid' the dimension values must |
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157 | be a list of a Numerical array of length N, N being the number |
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158 | of elements in the mesh. Otherwise it must be of dimension Nx2 |
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159 | |
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160 | The values will be stored in elements following their |
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161 | internal ordering. |
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162 | |
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163 | If selected location is vertices, values for centroid |
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164 | will be assigned interpolated values. |
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165 | In any other case, only values for the specified locations |
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166 | will be assigned and the others will be left undefined. |
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167 | """ |
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168 | |
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169 | from Numeric import array, Float |
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170 | |
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171 | values = array(values).astype(Float) |
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172 | |
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173 | N = self.centroid_values.shape[0] |
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174 | |
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175 | msg = 'Number of values must match number of elements' |
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176 | assert values.shape[0] == N, msg |
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177 | |
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178 | if location == 'centroids': |
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179 | assert len(values.shape) == 1, 'Values array must be 1d' |
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180 | self.centroid_values = values |
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181 | #elif location == 'edges': |
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182 | # assert len(values.shape) == 2, 'Values array must be 2d' |
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183 | # msg = 'Array must be N x 2' |
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184 | # self.edge_values = values |
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185 | else: |
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186 | assert len(values.shape) == 2, 'Values array must be 2d' |
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187 | msg = 'Array must be N x 2' |
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188 | assert values.shape[1] == 2, msg |
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189 | |
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190 | self.vertex_values = values |
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191 | |
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192 | |
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193 | def get_values(self, location='vertices', indices = None): |
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194 | """get values for quantity |
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195 | |
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196 | return X, Compatible list, Numeric array (see below) |
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197 | location: Where values are to be stored. |
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198 | Permissible options are: vertices, edges, centroid |
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199 | and unique vertices. Default is 'vertices' |
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200 | |
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201 | In case of location == 'centroids' the dimension values must |
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202 | be a list of a Numerical array of length N, N being the number |
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203 | of elements. Otherwise it must be of dimension Nx3 |
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204 | |
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205 | The returned values with be a list the length of indices |
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206 | (N if indices = None). Each value will be a list of the three |
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207 | vertex values for this quantity. |
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208 | |
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209 | Indices is the set of element ids that the operation applies to. |
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210 | |
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211 | """ |
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212 | from Numeric import take |
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213 | |
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214 | #if location not in ['vertices', 'centroids', 'edges', 'unique vertices']: |
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215 | if location not in ['vertices', 'centroids', 'unique vertices']: |
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216 | msg = 'Invalid location: %s' %location |
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217 | raise msg |
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218 | |
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219 | import types, Numeric |
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220 | assert type(indices) in [types.ListType, types.NoneType, |
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221 | Numeric.ArrayType],\ |
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222 | 'Indices must be a list or None' |
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223 | |
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224 | if location == 'centroids': |
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225 | if (indices == None): |
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226 | indices = range(len(self)) |
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227 | return take(self.centroid_values,indices) |
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228 | #elif location == 'edges': |
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229 | # if (indices == None): |
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230 | # indices = range(len(self)) |
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231 | # return take(self.edge_values,indices) |
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232 | elif location == 'unique vertices': |
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233 | if (indices == None): |
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234 | indices=range(self.domain.coordinates.shape[0]) |
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235 | vert_values = [] |
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236 | #Go through list of unique vertices |
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237 | for unique_vert_id in indices: |
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238 | triangles = self.domain.vertexlist[unique_vert_id] |
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239 | |
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240 | #In case there are unused points |
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241 | if triangles is None: |
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242 | msg = 'Unique vertex not associated with triangles' |
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243 | raise msg |
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244 | |
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245 | # Go through all triangle, vertex pairs |
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246 | # Average the values |
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247 | sum = 0 |
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248 | for triangle_id, vertex_id in triangles: |
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249 | sum += self.vertex_values[triangle_id, vertex_id] |
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250 | vert_values.append(sum/len(triangles)) |
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251 | return Numeric.array(vert_values) |
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252 | else: |
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253 | if (indices == None): |
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254 | indices = range(len(self)) |
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255 | return take(self.vertex_values,indices) |
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256 | |
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257 | #Method for outputting model results |
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258 | #FIXME: Split up into geometric and numeric stuff. |
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259 | #FIXME: Geometric (X,Y,V) should live in mesh.py |
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260 | #FIXME: STill remember to move XY to mesh |
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261 | def get_vertex_values(self, |
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262 | #xy=True, |
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263 | x=True, |
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264 | smooth = None, |
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265 | precision = None, |
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266 | reduction = None): |
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267 | """Return vertex values like an OBJ format |
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268 | |
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269 | The vertex values are returned as one sequence in the 1D float array A. |
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270 | If requested the coordinates will be returned in 1D arrays X and Y. |
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271 | |
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272 | The connectivity is represented as an integer array, V, of dimension |
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273 | M x 3, where M is the number of volumes. Each row has three indices |
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274 | into the X, Y, A arrays defining the triangle. |
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275 | |
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276 | if smooth is True, vertex values corresponding to one common |
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277 | coordinate set will be smoothed according to the given |
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278 | reduction operator. In this case vertex coordinates will be |
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279 | de-duplicated. |
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280 | |
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281 | If no smoothings is required, vertex coordinates and values will |
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282 | be aggregated as a concatenation of values at |
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283 | vertices 0, vertices 1 and vertices 2 |
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284 | |
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285 | |
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286 | Calling convention |
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287 | if xy is True: |
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288 | X,Y,A,V = get_vertex_values |
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289 | else: |
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290 | A,V = get_vertex_values |
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291 | |
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292 | """ |
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293 | |
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294 | from Numeric import concatenate, zeros, Float, Int, array, reshape |
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295 | |
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296 | |
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297 | if smooth is None: |
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298 | smooth = self.domain.smooth |
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299 | |
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300 | if precision is None: |
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301 | precision = Float |
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302 | |
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303 | if reduction is None: |
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304 | reduction = self.domain.reduction |
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305 | |
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306 | #Create connectivity |
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307 | |
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308 | if smooth == True: |
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309 | |
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310 | V = self.domain.get_vertices() |
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311 | N = len(self.domain.vertexlist) |
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312 | #N = len(self.domain.vertices) |
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313 | A = zeros(N, precision) |
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314 | |
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315 | #Smoothing loop |
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316 | for k in range(N): |
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317 | L = self.domain.vertexlist[k] |
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318 | #L = self.domain.vertices[k] |
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319 | |
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320 | #Go through all triangle, vertex pairs |
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321 | #contributing to vertex k and register vertex value |
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322 | |
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323 | if L is None: continue #In case there are unused points |
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324 | |
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325 | contributions = [] |
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326 | for volume_id, vertex_id in L: |
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327 | v = self.vertex_values[volume_id, vertex_id] |
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328 | contributions.append(v) |
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329 | |
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330 | A[k] = reduction(contributions) |
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331 | |
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332 | |
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333 | #if xy is True: |
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334 | if x is True: |
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335 | #X = self.domain.coordinates[:,0].astype(precision) |
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336 | X = self.domain.coordinates[:].astype(precision) |
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337 | #Y = self.domain.coordinates[:,1].astype(precision) |
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338 | |
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339 | #return X, Y, A, V |
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340 | return X, A, V |
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341 | |
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342 | #else: |
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343 | return A, V |
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344 | else: |
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345 | #Don't smooth |
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346 | #obj machinery moved to general_mesh |
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347 | |
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348 | # Create a V like [[0 1 2], [3 4 5]....[3*m-2 3*m-1 3*m]] |
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349 | # These vert_id's will relate to the verts created below |
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350 | #m = len(self.domain) #Number of volumes |
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351 | #M = 3*m #Total number of unique vertices |
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352 | #V = reshape(array(range(M)).astype(Int), (m,3)) |
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353 | |
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354 | #V = self.domain.get_triangles(obj=True) |
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355 | V = self.domain.get_vertices |
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356 | #FIXME use get_vertices, when ready |
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357 | |
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358 | A = self.vertex_values.flat |
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359 | |
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360 | #Do vertex coordinates |
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361 | #if xy is True: |
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362 | if x is True: |
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363 | C = self.domain.get_vertex_coordinates() |
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364 | |
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365 | X = C[:,0:6:2].copy() |
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366 | Y = C[:,1:6:2].copy() |
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367 | |
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368 | return X.flat, Y.flat, A, V |
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369 | else: |
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370 | return A, V |
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371 | |
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372 | def get_integral(self): |
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373 | """Compute the integral of quantity across entire domain |
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374 | """ |
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375 | integral = 0 |
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376 | for k in range(self.domain.number_of_elements): |
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377 | area = self.domain.areas[k] |
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378 | qc = self.centroid_values[k] |
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379 | integral += qc*area |
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380 | |
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381 | return integral |
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382 | |
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383 | class Conserved_quantity(Quantity): |
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384 | """Class conserved quantity adds to Quantity: |
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385 | |
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386 | storage and method for updating, and |
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387 | methods for extrapolation from centropid to vertices inluding |
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388 | gradients and limiters |
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389 | """ |
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390 | |
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391 | def __init__(self, domain, vertex_values=None): |
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392 | Quantity.__init__(self, domain, vertex_values) |
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393 | |
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394 | from Numeric import zeros, Float |
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395 | |
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396 | #Allocate space for boundary values |
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397 | #L = len(domain.boundary) |
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398 | self.boundary_values = zeros(2, Float) #assumes no parrellism |
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399 | |
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400 | #Allocate space for updates of conserved quantities by |
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401 | #flux calculations and forcing functions |
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402 | |
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403 | N = domain.number_of_elements |
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404 | self.explicit_update = zeros(N, Float ) |
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405 | self.semi_implicit_update = zeros(N, Float ) |
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406 | |
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407 | self.gradients = zeros(N, Float) |
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408 | self.qmax = zeros(self.centroid_values.shape, Float) |
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409 | self.qmin = zeros(self.centroid_values.shape, Float) |
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410 | |
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411 | self.beta = domain.beta |
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412 | |
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413 | def update(self, timestep): |
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414 | """Update centroid values based on values stored in |
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415 | explicit_update and semi_implicit_update as well as given timestep |
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416 | """ |
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417 | |
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418 | from Numeric import sum, equal, ones, Float |
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419 | |
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420 | N = self.centroid_values.shape[0] |
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421 | |
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422 | #print "pre update",self.centroid_values |
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423 | #print "timestep",timestep |
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424 | #print min(self.domain.areas) |
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425 | #print "explicit_update", self.explicit_update |
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426 | |
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427 | #Explicit updates |
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428 | self.centroid_values += timestep*self.explicit_update |
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429 | |
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430 | #print "post update",self.centroid_values |
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431 | |
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432 | #Semi implicit updates |
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433 | denominator = ones(N, Float)-timestep*self.semi_implicit_update |
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434 | |
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435 | if sum(equal(denominator, 0.0)) > 0.0: |
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436 | msg = 'Zero division in semi implicit update. Call Stephen :-)' |
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437 | raise msg |
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438 | else: |
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439 | #Update conserved_quantities from semi implicit updates |
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440 | self.centroid_values /= denominator |
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441 | |
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442 | |
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443 | def compute_gradients(self): |
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444 | """Compute gradients of piecewise linear function defined by centroids of |
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445 | neighbouring volumes. |
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446 | """ |
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447 | |
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448 | |
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449 | from Numeric import array, zeros, Float |
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450 | |
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451 | N = self.centroid_values.shape[0] |
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452 | |
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453 | |
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454 | G = self.gradients |
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455 | Q = self.centroid_values |
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456 | X = self.domain.centroids |
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457 | |
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458 | for k in range(N): |
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459 | |
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460 | # first and last elements have boundaries |
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461 | |
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462 | if k == 0: |
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463 | |
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464 | #Get data |
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465 | k0 = k |
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466 | k1 = k+1 |
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467 | |
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468 | q0 = Q[k0] |
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469 | q1 = Q[k1] |
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470 | |
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471 | x0 = X[k0] #V0 centroid |
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472 | x1 = X[k1] #V1 centroid |
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473 | |
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474 | #Gradient |
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475 | G[k] = (q1 - q0)/(x1 - x0) |
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476 | |
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477 | elif k == N-1: |
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478 | |
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479 | #Get data |
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480 | k0 = k |
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481 | k1 = k-1 |
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482 | |
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483 | q0 = Q[k0] |
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484 | q1 = Q[k1] |
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485 | |
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486 | x0 = X[k0] #V0 centroid |
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487 | x1 = X[k1] #V1 centroid |
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488 | |
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489 | #Gradient |
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490 | G[k] = (q1 - q0)/(x1 - x0) |
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491 | |
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492 | else: |
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493 | #Interior Volume (2 neighbours) |
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494 | |
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495 | #Get data |
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496 | k0 = k-1 |
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497 | k2 = k+1 |
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498 | |
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499 | q0 = Q[k0] |
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500 | q1 = Q[k] |
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501 | q2 = Q[k2] |
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502 | |
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503 | x0 = X[k0] #V0 centroid |
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504 | x1 = X[k] #V1 centroid (Self) |
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505 | x2 = X[k2] #V2 centroid |
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506 | |
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507 | #Gradient |
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508 | #G[k] = (q2-q0)/(x2-x0) |
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509 | G[k] = ((q0-q1)/(x0-x1)*(x2-x1) - (q2-q1)/(x2-x1)*(x0-x1))/(x2-x0) |
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510 | |
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511 | |
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512 | def compute_minmod_gradients(self): |
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513 | """Compute gradients of piecewise linear function defined by centroids of |
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514 | neighbouring volumes. |
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515 | """ |
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516 | |
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517 | from Numeric import array, zeros, Float,sign |
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518 | |
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519 | def xmin(a,b): |
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520 | return 0.5*(sign(a)+sign(b))*min(abs(a),abs(b)) |
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521 | |
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522 | def xmic(t,a,b): |
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523 | return xmin(t*xmin(a,b), 0.50*(a+b) ) |
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524 | |
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525 | |
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526 | |
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527 | N = self.centroid_values.shape[0] |
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528 | |
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529 | |
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530 | G = self.gradients |
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531 | Q = self.centroid_values |
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532 | X = self.domain.centroids |
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533 | |
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534 | for k in range(N): |
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535 | |
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536 | # first and last elements have boundaries |
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537 | |
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538 | if k == 0: |
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539 | |
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540 | #Get data |
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541 | k0 = k |
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542 | k1 = k+1 |
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543 | |
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544 | q0 = Q[k0] |
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545 | q1 = Q[k1] |
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546 | |
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547 | x0 = X[k0] #V0 centroid |
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548 | x1 = X[k1] #V1 centroid |
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549 | |
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550 | #Gradient |
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551 | G[k] = (q1 - q0)/(x1 - x0) |
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552 | |
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553 | elif k == N-1: |
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554 | |
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555 | #Get data |
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556 | k0 = k |
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557 | k1 = k-1 |
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558 | |
---|
559 | q0 = Q[k0] |
---|
560 | q1 = Q[k1] |
---|
561 | |
---|
562 | x0 = X[k0] #V0 centroid |
---|
563 | x1 = X[k1] #V1 centroid |
---|
564 | |
---|
565 | #Gradient |
---|
566 | G[k] = (q1 - q0)/(x1 - x0) |
---|
567 | |
---|
568 | elif (self.domain.wet_nodes[k,0] == 2) & (self.domain.wet_nodes[k,1] == 2): |
---|
569 | G[k] = 0.0 |
---|
570 | |
---|
571 | else: |
---|
572 | #Interior Volume (2 neighbours) |
---|
573 | |
---|
574 | #Get data |
---|
575 | k0 = k-1 |
---|
576 | k2 = k+1 |
---|
577 | |
---|
578 | q0 = Q[k0] |
---|
579 | q1 = Q[k] |
---|
580 | q2 = Q[k2] |
---|
581 | |
---|
582 | x0 = X[k0] #V0 centroid |
---|
583 | x1 = X[k] #V1 centroid (Self) |
---|
584 | x2 = X[k2] #V2 centroid |
---|
585 | |
---|
586 | # assuming uniform grid |
---|
587 | d1 = (q1 - q0)/(x1-x0) |
---|
588 | d2 = (q2 - q1)/(x2-x1) |
---|
589 | |
---|
590 | #Gradient |
---|
591 | #G[k] = (d1+d2)*0.5 |
---|
592 | #G[k] = (d1*(x2-x1) - d2*(x0-x1))/(x2-x0) |
---|
593 | G[k] = xmic( self.domain.beta, d1, d2 ) |
---|
594 | |
---|
595 | |
---|
596 | def extrapolate_first_order(self): |
---|
597 | """Extrapolate conserved quantities from centroid to |
---|
598 | vertices for each volume using |
---|
599 | first order scheme. |
---|
600 | """ |
---|
601 | |
---|
602 | qc = self.centroid_values |
---|
603 | qv = self.vertex_values |
---|
604 | |
---|
605 | for i in range(2): |
---|
606 | qv[:,i] = qc |
---|
607 | |
---|
608 | |
---|
609 | def extrapolate_second_order(self): |
---|
610 | """Extrapolate conserved quantities from centroid to |
---|
611 | vertices for each volume using |
---|
612 | second order scheme. |
---|
613 | """ |
---|
614 | if self.domain.limiter == "pyvolution": |
---|
615 | #Z = self.gradients |
---|
616 | #print "gradients 1",Z |
---|
617 | self.compute_gradients() |
---|
618 | #print "gradients 2",Z |
---|
619 | |
---|
620 | #Z = self.gradients |
---|
621 | #print "gradients 1",Z |
---|
622 | #self.compute_minmod_gradients() |
---|
623 | #print "gradients 2", Z |
---|
624 | |
---|
625 | G = self.gradients |
---|
626 | V = self.domain.vertices |
---|
627 | qc = self.centroid_values |
---|
628 | qv = self.vertex_values |
---|
629 | |
---|
630 | #Check each triangle |
---|
631 | for k in range(self.domain.number_of_elements): |
---|
632 | #Centroid coordinates |
---|
633 | x = self.domain.centroids[k] |
---|
634 | |
---|
635 | #vertex coordinates |
---|
636 | x0, x1 = V[k,:] |
---|
637 | |
---|
638 | #Extrapolate |
---|
639 | qv[k,0] = qc[k] + G[k]*(x0-x) |
---|
640 | qv[k,1] = qc[k] + G[k]*(x1-x) |
---|
641 | self.limit_pyvolution() |
---|
642 | elif self.domain.limiter == "steve_minmod": |
---|
643 | self.limit_minmod() |
---|
644 | else: |
---|
645 | self.limit_range() |
---|
646 | |
---|
647 | |
---|
648 | |
---|
649 | def limit_minmod(self): |
---|
650 | #Z = self.gradients |
---|
651 | #print "gradients 1",Z |
---|
652 | self.compute_minmod_gradients() |
---|
653 | #print "gradients 2", Z |
---|
654 | |
---|
655 | G = self.gradients |
---|
656 | V = self.domain.vertices |
---|
657 | qc = self.centroid_values |
---|
658 | qv = self.vertex_values |
---|
659 | |
---|
660 | #Check each triangle |
---|
661 | for k in range(self.domain.number_of_elements): |
---|
662 | #Centroid coordinates |
---|
663 | x = self.domain.centroids[k] |
---|
664 | |
---|
665 | #vertex coordinates |
---|
666 | x0, x1 = V[k,:] |
---|
667 | |
---|
668 | #Extrapolate |
---|
669 | qv[k,0] = qc[k] + G[k]*(x0-x) |
---|
670 | qv[k,1] = qc[k] + G[k]*(x1-x) |
---|
671 | |
---|
672 | |
---|
673 | def limit_pyvolution(self): |
---|
674 | """ |
---|
675 | Limit slopes for each volume to eliminate artificial variance |
---|
676 | introduced by e.g. second order extrapolator |
---|
677 | |
---|
678 | This is an unsophisticated limiter as it does not take into |
---|
679 | account dependencies among quantities. |
---|
680 | |
---|
681 | precondition: |
---|
682 | vertex values are estimated from gradient |
---|
683 | postcondition: |
---|
684 | vertex values are updated |
---|
685 | """ |
---|
686 | from Numeric import zeros, Float |
---|
687 | |
---|
688 | N = self.domain.number_of_elements |
---|
689 | beta = self.domain.beta |
---|
690 | #beta = 0.8 |
---|
691 | |
---|
692 | qc = self.centroid_values |
---|
693 | qv = self.vertex_values |
---|
694 | |
---|
695 | #Find min and max of this and neighbour's centroid values |
---|
696 | qmax = self.qmax |
---|
697 | qmin = self.qmin |
---|
698 | |
---|
699 | for k in range(N): |
---|
700 | qmax[k] = qmin[k] = qc[k] |
---|
701 | for i in range(2): |
---|
702 | n = self.domain.neighbours[k,i] |
---|
703 | if n >= 0: |
---|
704 | qn = qc[n] #Neighbour's centroid value |
---|
705 | |
---|
706 | qmin[k] = min(qmin[k], qn) |
---|
707 | qmax[k] = max(qmax[k], qn) |
---|
708 | |
---|
709 | |
---|
710 | #Diffences between centroids and maxima/minima |
---|
711 | dqmax = qmax - qc |
---|
712 | dqmin = qmin - qc |
---|
713 | |
---|
714 | #Deltas between vertex and centroid values |
---|
715 | dq = zeros(qv.shape, Float) |
---|
716 | for i in range(2): |
---|
717 | dq[:,i] = qv[:,i] - qc |
---|
718 | |
---|
719 | #Phi limiter |
---|
720 | for k in range(N): |
---|
721 | |
---|
722 | #Find the gradient limiter (phi) across vertices |
---|
723 | phi = 1.0 |
---|
724 | for i in range(2): |
---|
725 | r = 1.0 |
---|
726 | if (dq[k,i] > 0): r = dqmax[k]/dq[k,i] |
---|
727 | if (dq[k,i] < 0): r = dqmin[k]/dq[k,i] |
---|
728 | |
---|
729 | phi = min( min(r*beta, 1), phi ) |
---|
730 | |
---|
731 | #Then update using phi limiter |
---|
732 | for i in range(2): |
---|
733 | qv[k,i] = qc[k] + phi*dq[k,i] |
---|
734 | |
---|
735 | def limit_range(self): |
---|
736 | import sys |
---|
737 | from Numeric import zeros, Float |
---|
738 | from util import minmod, minmod_kurganov, maxmod, vanleer, vanalbada |
---|
739 | limiter = self.domain.limiter |
---|
740 | #print limiter |
---|
741 | |
---|
742 | N = self.domain.number_of_elements |
---|
743 | qc = self.centroid_values |
---|
744 | qv = self.vertex_values |
---|
745 | C = self.domain.centroids |
---|
746 | X = self.domain.vertices |
---|
747 | beta_p = zeros(N,Float) |
---|
748 | beta_m = zeros(N,Float) |
---|
749 | beta_x = zeros(N,Float) |
---|
750 | |
---|
751 | for k in range(N): |
---|
752 | |
---|
753 | n0 = self.domain.neighbours[k,0] |
---|
754 | n1 = self.domain.neighbours[k,1] |
---|
755 | |
---|
756 | if ( n0 >= 0) & (n1 >= 0): |
---|
757 | #SLOPE DERIVATIVE LIMIT |
---|
758 | beta_p[k] = (qc[k]-qc[k-1])/(C[k]-C[k-1]) |
---|
759 | beta_m[k] = (qc[k+1]-qc[k])/(C[k+1]-C[k]) |
---|
760 | beta_x[k] = (qc[k+1]-qc[k-1])/(C[k+1]-C[k-1]) |
---|
761 | |
---|
762 | dq = zeros(qv.shape, Float) |
---|
763 | for i in range(2): |
---|
764 | dq[:,i] =self.domain.vertices[:,i]-self.domain.centroids |
---|
765 | |
---|
766 | #Phi limiter |
---|
767 | for k in range(N): |
---|
768 | n0 = self.domain.neighbours[k,0] |
---|
769 | n1 = self.domain.neighbours[k,1] |
---|
770 | if n0 < 0: |
---|
771 | phi = (qc[k+1] - qc[k])/(C[k+1] - C[k]) |
---|
772 | elif n1 < 0: |
---|
773 | phi = (qc[k] - qc[k-1])/(C[k] - C[k-1]) |
---|
774 | elif (self.domain.wet_nodes[k,0] == 2) & (self.domain.wet_nodes[k,1] == 2): |
---|
775 | phi = 0.0 |
---|
776 | else: |
---|
777 | if limiter == "minmod": |
---|
778 | phi = minmod(beta_p[k],beta_m[k]) |
---|
779 | |
---|
780 | elif limiter == "minmod_kurganov":#Change this |
---|
781 | # Also known as monotonized central difference limiter |
---|
782 | # if theta = 2.0 |
---|
783 | theta = 2.0 |
---|
784 | phi = minmod_kurganov(theta*beta_p[k],theta*beta_m[k],beta_x[k]) |
---|
785 | elif limiter == "superbee": |
---|
786 | slope1 = minmod(beta_m[k],2.0*beta_p[k]) |
---|
787 | slope2 = minmod(2.0*beta_m[k],beta_p[k]) |
---|
788 | phi = maxmod(slope1,slope2) |
---|
789 | |
---|
790 | elif limiter == "vanleer": |
---|
791 | phi = vanleer(beta_p[k],beta_m[k]) |
---|
792 | |
---|
793 | elif limiter == "vanalbada": |
---|
794 | phi = vanalbada(beta_m[k],beta_p[k]) |
---|
795 | |
---|
796 | for i in range(2): |
---|
797 | qv[k,i] = qc[k] + phi*dq[k,i] |
---|
798 | |
---|
799 | def limit_steve_slope(self): |
---|
800 | |
---|
801 | import sys |
---|
802 | from Numeric import zeros, Float |
---|
803 | from util import minmod, minmod_kurganov, maxmod, vanleer |
---|
804 | |
---|
805 | N = self.domain.number_of_elements |
---|
806 | limiter = self.domain.limiter |
---|
807 | limiter_type = self.domain.limiter_type |
---|
808 | |
---|
809 | qc = self.centroid_values |
---|
810 | qv = self.vertex_values |
---|
811 | |
---|
812 | #Find min and max of this and neighbour's centroid values |
---|
813 | beta_p = zeros(N,Float) |
---|
814 | beta_m = zeros(N,Float) |
---|
815 | beta_x = zeros(N,Float) |
---|
816 | C = self.domain.centroids |
---|
817 | X = self.domain.vertices |
---|
818 | |
---|
819 | for k in range(N): |
---|
820 | |
---|
821 | n0 = self.domain.neighbours[k,0] |
---|
822 | n1 = self.domain.neighbours[k,1] |
---|
823 | |
---|
824 | if (n0 >= 0) & (n1 >= 0): |
---|
825 | # Check denominator not zero |
---|
826 | if (qc[k+1]-qc[k]) == 0.0: |
---|
827 | beta_p[k] = float(sys.maxint) |
---|
828 | beta_m[k] = float(sys.maxint) |
---|
829 | else: |
---|
830 | #STEVE LIMIT |
---|
831 | beta_p[k] = (qc[k]-qc[k-1])/(qc[k+1]-qc[k]) |
---|
832 | beta_m[k] = (qc[k+2]-qc[k+1])/(qc[k+1]-qc[k]) |
---|
833 | |
---|
834 | #Deltas between vertex and centroid values |
---|
835 | dq = zeros(qv.shape, Float) |
---|
836 | for i in range(2): |
---|
837 | dq[:,i] =self.domain.vertices[:,i]-self.domain.centroids |
---|
838 | |
---|
839 | #Phi limiter |
---|
840 | for k in range(N): |
---|
841 | |
---|
842 | phi = 0.0 |
---|
843 | if limiter == "flux_minmod": |
---|
844 | #FLUX MINMOD |
---|
845 | phi = minmod_kurganov(1.0,beta_m[k],beta_p[k]) |
---|
846 | elif limiter == "flux_superbee": |
---|
847 | #FLUX SUPERBEE |
---|
848 | phi = max(0.0,min(1.0,2.0*beta_m[k]),min(2.0,beta_m[k]))+max(0.0,min(1.0,2.0*beta_p[k]),min(2.0,beta_p[k]))-1.0 |
---|
849 | elif limiter == "flux_muscl": |
---|
850 | #FLUX MUSCL |
---|
851 | phi = max(0.0,min(2.0,2.0*beta_m[k],2.0*beta_p[k],0.5*(beta_m[k]+beta_p[k]))) |
---|
852 | elif limiter == "flux_vanleer": |
---|
853 | #FLUX VAN LEER |
---|
854 | phi = (beta_m[k]+abs(beta_m[k]))/(1.0+abs(beta_m[k]))+(beta_p[k]+abs(beta_p[k]))/(1.0+abs(beta_p[k]))-1.0 |
---|
855 | |
---|
856 | #Then update using phi limiter |
---|
857 | n = self.domain.neighbours[k,1] |
---|
858 | if n>=0: |
---|
859 | #qv[k,0] = qc[k] - 0.5*phi*(qc[k+1]-qc[k]) |
---|
860 | #qv[k,1] = qc[k] + 0.5*phi*(qc[k+1]-qc[k]) |
---|
861 | qv[k,0] = qc[k] + 0.5*phi*(qv[k,0]-qc[k]) |
---|
862 | qv[k,1] = qc[k] + 0.5*phi*(qv[k,1]-qc[k]) |
---|
863 | else: |
---|
864 | qv[k,i] = qc[k] |
---|
865 | |
---|
866 | |
---|
867 | def newLinePlot(title='Simple Plot'): |
---|
868 | import Gnuplot |
---|
869 | g = Gnuplot.Gnuplot() |
---|
870 | g.title(title) |
---|
871 | g('set data style linespoints') |
---|
872 | g.xlabel('x') |
---|
873 | g.ylabel('y') |
---|
874 | return g |
---|
875 | |
---|
876 | def linePlot(g,x,y): |
---|
877 | import Gnuplot |
---|
878 | g.plot(Gnuplot.PlotItems.Data(x.flat,y.flat)) |
---|
879 | |
---|
880 | |
---|
881 | |
---|
882 | |
---|
883 | |
---|
884 | if __name__ == "__main__": |
---|
885 | #from domain import Domain |
---|
886 | from shallow_water_1d import Domain |
---|
887 | from Numeric import arange |
---|
888 | |
---|
889 | points1 = [0.0, 1.0, 2.0, 3.0] |
---|
890 | vertex_values = [[1.0,2.0],[4.0,5.0],[-1.0,2.0]] |
---|
891 | |
---|
892 | D1 = Domain(points1) |
---|
893 | |
---|
894 | Q1 = Conserved_quantity(D1, vertex_values) |
---|
895 | |
---|
896 | print Q1.vertex_values |
---|
897 | print Q1.centroid_values |
---|
898 | |
---|
899 | new_vertex_values = [[2.0,1.0],[3.0,4.0],[-2.0,4.0]] |
---|
900 | |
---|
901 | Q1.set_values(new_vertex_values) |
---|
902 | |
---|
903 | print Q1.vertex_values |
---|
904 | print Q1.centroid_values |
---|
905 | |
---|
906 | new_centroid_values = [20,30,40] |
---|
907 | Q1.set_values(new_centroid_values,'centroids') |
---|
908 | |
---|
909 | print Q1.vertex_values |
---|
910 | print Q1.centroid_values |
---|
911 | |
---|
912 | class FunClass: |
---|
913 | def __init__(self,value): |
---|
914 | self.value = value |
---|
915 | |
---|
916 | def __call__(self,x): |
---|
917 | return self.value*(x**2) |
---|
918 | |
---|
919 | |
---|
920 | fun = FunClass(1.0) |
---|
921 | Q1.set_values(fun,'vertices') |
---|
922 | |
---|
923 | print Q1.vertex_values |
---|
924 | print Q1.centroid_values |
---|
925 | |
---|
926 | Xc = Q1.domain.vertices |
---|
927 | Qc = Q1.vertex_values |
---|
928 | print Xc |
---|
929 | print Qc |
---|
930 | |
---|
931 | Qc[1,0] = 3 |
---|
932 | |
---|
933 | Q1.beta = 1.0 |
---|
934 | Q1.extrapolate_second_order() |
---|
935 | Q1.limit_minmod() |
---|
936 | |
---|
937 | g1 = newLinePlot('plot 1') |
---|
938 | linePlot(g1,Xc,Qc) |
---|
939 | |
---|
940 | points2 = arange(10) |
---|
941 | D2 = Domain(points2) |
---|
942 | |
---|
943 | Q2 = Conserved_quantity(D2) |
---|
944 | Q2.set_values(fun,'vertices') |
---|
945 | Xc = Q2.domain.vertices |
---|
946 | Qc = Q2.vertex_values |
---|
947 | |
---|
948 | g2 = newLinePlot('plot 2') |
---|
949 | linePlot(g2,Xc,Qc) |
---|
950 | |
---|
951 | |
---|
952 | |
---|
953 | Q2.extrapolate_second_order() |
---|
954 | Q2.limit_minmod() |
---|
955 | Xc = Q2.domain.vertices |
---|
956 | Qc = Q2.vertex_values |
---|
957 | |
---|
958 | print Q2.centroid_values |
---|
959 | print Qc |
---|
960 | raw_input('press_return') |
---|
961 | |
---|
962 | g3 = newLinePlot('plot 3') |
---|
963 | linePlot(g3,Xc,Qc) |
---|
964 | raw_input('press return') |
---|
965 | |
---|
966 | |
---|
967 | for i in range(10): |
---|
968 | fun = FunClass(i/10.0) |
---|
969 | Q2.set_values(fun,'vertices') |
---|
970 | Qc = Q2.vertex_values |
---|
971 | linePlot(g3,Xc,Qc) |
---|
972 | |
---|
973 | raw_input('press return') |
---|
974 | |
---|