1 | """Least squares fitting. |
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2 | |
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3 | Implements a penalised least-squares fit. |
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4 | putting point data onto the mesh. |
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5 | |
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6 | The penalty term (or smoothing term) is controlled by the smoothing |
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7 | parameter alpha. |
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8 | With a value of alpha=0, the fit function will attempt |
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9 | to interpolate as closely as possible in the least-squares sense. |
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10 | With values alpha > 0, a certain amount of smoothing will be applied. |
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11 | A positive alpha is essential in cases where there are too few |
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12 | data points. |
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13 | A negative alpha is not allowed. |
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14 | A typical value of alpha is 1.0e-6 |
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15 | |
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16 | |
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17 | Ole Nielsen, Stephen Roberts, Duncan Gray, Christopher Zoppou |
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18 | Geoscience Australia, 2004. |
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19 | |
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20 | TO DO |
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21 | * test geo_ref, geo_spatial |
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22 | |
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23 | IDEAS |
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24 | * (DSG-) Change the interface of fit, so a domain object can |
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25 | be passed in. (I don't know if this is feasible). If could |
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26 | save time/memory. |
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27 | """ |
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28 | import types |
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29 | |
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30 | from anuga.abstract_2d_finite_volumes.neighbour_mesh import Mesh |
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31 | from anuga.caching import cache |
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32 | from anuga.geospatial_data.geospatial_data import Geospatial_data, \ |
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33 | ensure_absolute |
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34 | from anuga.fit_interpolate.general_fit_interpolate import FitInterpolate |
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35 | from anuga.utilities.sparse import Sparse, Sparse_CSR |
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36 | from anuga.utilities.polygon import inside_polygon, is_inside_polygon |
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37 | from anuga.fit_interpolate.search_functions import search_tree_of_vertices |
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38 | |
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39 | from anuga.utilities.cg_solve import conjugate_gradient |
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40 | from anuga.utilities.numerical_tools import ensure_numeric, gradient |
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41 | from anuga.config import default_smoothing_parameter as DEFAULT_ALPHA |
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42 | |
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43 | import exceptions |
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44 | class TooFewPointsError(exceptions.Exception): pass |
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45 | class VertsWithNoTrianglesError(exceptions.Exception): pass |
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46 | |
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47 | import Numeric as num |
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48 | |
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49 | |
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50 | class Fit(FitInterpolate): |
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51 | |
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52 | def __init__(self, |
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53 | vertex_coordinates=None, |
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54 | triangles=None, |
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55 | mesh=None, |
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56 | mesh_origin=None, |
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57 | alpha = None, |
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58 | verbose=False, |
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59 | max_vertices_per_cell=None): |
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60 | |
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61 | |
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62 | """ |
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63 | Fit data at points to the vertices of a mesh. |
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64 | |
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65 | Inputs: |
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66 | |
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67 | vertex_coordinates: List of coordinate pairs [xi, eta] of |
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68 | points constituting a mesh (or an m x 2 Numeric array or |
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69 | a geospatial object) |
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70 | Points may appear multiple times |
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71 | (e.g. if vertices have discontinuities) |
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72 | |
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73 | triangles: List of 3-tuples (or a Numeric array) of |
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74 | integers representing indices of all vertices in the mesh. |
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75 | |
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76 | mesh_origin: A geo_reference object or 3-tuples consisting of |
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77 | UTM zone, easting and northing. |
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78 | If specified vertex coordinates are assumed to be |
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79 | relative to their respective origins. |
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80 | |
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81 | max_vertices_per_cell: Number of vertices in a quad tree cell |
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82 | at which the cell is split into 4. |
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83 | |
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84 | Note: Don't supply a vertex coords as a geospatial object and |
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85 | a mesh origin, since geospatial has its own mesh origin. |
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86 | |
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87 | |
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88 | Usage, |
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89 | To use this in a blocking way, call build_fit_subset, with z info, |
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90 | and then fit, with no point coord, z info. |
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91 | |
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92 | """ |
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93 | # Initialise variabels |
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94 | if alpha is None: |
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95 | self.alpha = DEFAULT_ALPHA |
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96 | else: |
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97 | self.alpha = alpha |
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98 | |
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99 | FitInterpolate.__init__(self, |
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100 | vertex_coordinates, |
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101 | triangles, |
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102 | mesh, |
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103 | mesh_origin, |
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104 | verbose, |
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105 | max_vertices_per_cell) |
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106 | |
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107 | m = self.mesh.number_of_nodes # Nbr of basis functions (vertices) |
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108 | |
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109 | self.AtA = None |
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110 | self.Atz = None |
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111 | |
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112 | self.point_count = 0 |
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113 | if self.alpha <> 0: |
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114 | if verbose: print 'Building smoothing matrix' |
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115 | self._build_smoothing_matrix_D() |
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116 | |
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117 | bd_poly = self.mesh.get_boundary_polygon() |
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118 | self.mesh_boundary_polygon = ensure_numeric(bd_poly) |
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119 | |
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120 | def _build_coefficient_matrix_B(self, |
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121 | verbose = False): |
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122 | """ |
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123 | Build final coefficient matrix |
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124 | |
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125 | Precon |
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126 | If alpha is not zero, matrix D has been built |
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127 | Matrix Ata has been built |
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128 | """ |
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129 | |
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130 | if self.alpha <> 0: |
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131 | #if verbose: print 'Building smoothing matrix' |
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132 | #self._build_smoothing_matrix_D() |
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133 | self.B = self.AtA + self.alpha*self.D |
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134 | else: |
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135 | self.B = self.AtA |
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136 | |
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137 | # Convert self.B matrix to CSR format for faster matrix vector |
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138 | self.B = Sparse_CSR(self.B) |
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139 | |
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140 | def _build_smoothing_matrix_D(self): |
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141 | """Build m x m smoothing matrix, where |
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142 | m is the number of basis functions phi_k (one per vertex) |
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143 | |
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144 | The smoothing matrix is defined as |
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145 | |
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146 | D = D1 + D2 |
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147 | |
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148 | where |
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149 | |
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150 | [D1]_{k,l} = \int_\Omega |
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151 | \frac{\partial \phi_k}{\partial x} |
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152 | \frac{\partial \phi_l}{\partial x}\, |
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153 | dx dy |
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154 | |
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155 | [D2]_{k,l} = \int_\Omega |
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156 | \frac{\partial \phi_k}{\partial y} |
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157 | \frac{\partial \phi_l}{\partial y}\, |
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158 | dx dy |
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159 | |
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160 | |
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161 | The derivatives \frac{\partial \phi_k}{\partial x}, |
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162 | \frac{\partial \phi_k}{\partial x} for a particular triangle |
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163 | are obtained by computing the gradient a_k, b_k for basis function k |
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164 | """ |
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165 | |
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166 | # FIXME: algorithm might be optimised by computing local 9x9 |
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167 | # "element stiffness matrices: |
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168 | |
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169 | m = self.mesh.number_of_nodes # Nbr of basis functions (1/vertex) |
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170 | |
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171 | self.D = Sparse(m,m) |
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172 | |
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173 | # For each triangle compute contributions to D = D1+D2 |
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174 | for i in range(len(self.mesh)): |
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175 | |
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176 | # Get area |
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177 | area = self.mesh.areas[i] |
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178 | |
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179 | # Get global vertex indices |
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180 | v0 = self.mesh.triangles[i,0] |
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181 | v1 = self.mesh.triangles[i,1] |
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182 | v2 = self.mesh.triangles[i,2] |
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183 | |
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184 | # Get the three vertex_points |
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185 | xi0 = self.mesh.get_vertex_coordinate(i, 0) |
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186 | xi1 = self.mesh.get_vertex_coordinate(i, 1) |
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187 | xi2 = self.mesh.get_vertex_coordinate(i, 2) |
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188 | |
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189 | # Compute gradients for each vertex |
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190 | a0, b0 = gradient(xi0[0], xi0[1], xi1[0], xi1[1], xi2[0], xi2[1], |
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191 | 1, 0, 0) |
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192 | |
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193 | a1, b1 = gradient(xi0[0], xi0[1], xi1[0], xi1[1], xi2[0], xi2[1], |
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194 | 0, 1, 0) |
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195 | |
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196 | a2, b2 = gradient(xi0[0], xi0[1], xi1[0], xi1[1], xi2[0], xi2[1], |
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197 | 0, 0, 1) |
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198 | |
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199 | # Compute diagonal contributions |
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200 | self.D[v0,v0] += (a0*a0 + b0*b0)*area |
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201 | self.D[v1,v1] += (a1*a1 + b1*b1)*area |
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202 | self.D[v2,v2] += (a2*a2 + b2*b2)*area |
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203 | |
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204 | # Compute contributions for basis functions sharing edges |
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205 | e01 = (a0*a1 + b0*b1)*area |
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206 | self.D[v0,v1] += e01 |
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207 | self.D[v1,v0] += e01 |
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208 | |
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209 | e12 = (a1*a2 + b1*b2)*area |
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210 | self.D[v1,v2] += e12 |
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211 | self.D[v2,v1] += e12 |
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212 | |
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213 | e20 = (a2*a0 + b2*b0)*area |
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214 | self.D[v2,v0] += e20 |
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215 | self.D[v0,v2] += e20 |
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216 | |
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217 | def get_D(self): |
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218 | return self.D.todense() |
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219 | |
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220 | |
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221 | |
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222 | def _build_matrix_AtA_Atz(self, |
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223 | point_coordinates, |
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224 | z, |
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225 | verbose = False): |
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226 | """Build: |
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227 | AtA m x m interpolation matrix, and, |
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228 | Atz m x a interpolation matrix where, |
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229 | m is the number of basis functions phi_k (one per vertex) |
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230 | a is the number of data attributes |
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231 | |
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232 | This algorithm uses a quad tree data structure for fast binning of |
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233 | data points. |
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234 | |
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235 | If Ata is None, the matrices AtA and Atz are created. |
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236 | |
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237 | This function can be called again and again, with sub-sets of |
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238 | the point coordinates. Call fit to get the results. |
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239 | |
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240 | Preconditions |
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241 | z and points are numeric |
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242 | Point_coordindates and mesh vertices have the same origin. |
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243 | |
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244 | The number of attributes of the data points does not change |
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245 | """ |
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246 | |
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247 | # Build n x m interpolation matrix |
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248 | if self.AtA == None: |
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249 | # AtA and Atz need to be initialised. |
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250 | m = self.mesh.number_of_nodes |
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251 | if len(z.shape) > 1: |
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252 | att_num = z.shape[1] |
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253 | self.Atz = num.zeros((m,att_num), num.Float) |
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254 | else: |
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255 | att_num = 1 |
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256 | self.Atz = num.zeros((m,), num.Float) |
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257 | assert z.shape[0] == point_coordinates.shape[0] |
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258 | |
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259 | AtA = Sparse(m,m) |
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260 | # The memory damage has been done by now. |
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261 | else: |
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262 | AtA = self.AtA #Did this for speed, did ~nothing |
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263 | self.point_count += point_coordinates.shape[0] |
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264 | |
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265 | |
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266 | inside_indices = inside_polygon(point_coordinates, |
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267 | self.mesh_boundary_polygon, |
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268 | closed=True, |
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269 | verbose=False) # Suppress output |
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270 | |
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271 | n = len(inside_indices) |
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272 | |
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273 | # Compute matrix elements for points inside the mesh |
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274 | triangles = self.mesh.triangles # Shorthand |
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275 | for d, i in enumerate(inside_indices): |
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276 | # For each data_coordinate point |
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277 | # if verbose and d%((n+10)/10)==0: print 'Doing %d of %d' %(d, n) |
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278 | x = point_coordinates[i] |
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279 | |
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280 | element_found, sigma0, sigma1, sigma2, k = \ |
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281 | search_tree_of_vertices(self.root, self.mesh, x) |
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282 | |
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283 | if element_found is True: |
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284 | j0 = triangles[k,0] #Global vertex id for sigma0 |
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285 | j1 = triangles[k,1] #Global vertex id for sigma1 |
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286 | j2 = triangles[k,2] #Global vertex id for sigma2 |
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287 | |
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288 | sigmas = {j0:sigma0, j1:sigma1, j2:sigma2} |
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289 | js = [j0,j1,j2] |
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290 | |
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291 | for j in js: |
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292 | self.Atz[j] += sigmas[j]*z[i] |
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293 | #print "self.Atz building", self.Atz |
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294 | #print "self.Atz[j]", self.Atz[j] |
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295 | #print " sigmas[j]", sigmas[j] |
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296 | #print "z[i]",z[i] |
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297 | #print "result", sigmas[j]*z[i] |
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298 | |
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299 | for k in js: |
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300 | AtA[j,k] += sigmas[j]*sigmas[k] |
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301 | else: |
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302 | flag = is_inside_polygon(x, |
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303 | self.mesh_boundary_polygon, |
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304 | closed=True, |
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305 | verbose=False) # Suppress output |
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306 | msg = 'Point (%f, %f) is not inside mesh boundary' % tuple(x) |
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307 | assert flag is True, msg |
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308 | |
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309 | # FIXME(Ole): This is the message referred to in ticket:314 |
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310 | minx = min(self.mesh_boundary_polygon[:,0]) |
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311 | maxx = max(self.mesh_boundary_polygon[:,0]) |
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312 | miny = min(self.mesh_boundary_polygon[:,1]) |
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313 | maxy = max(self.mesh_boundary_polygon[:,1]) |
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314 | msg = 'Could not find triangle for point %s. ' % str(x) |
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315 | msg += 'Mesh boundary extent is (%.f, %.f), (%.f, %.f)'\ |
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316 | % (minx, maxx, miny, maxy) |
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317 | raise RuntimeError, msg |
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318 | |
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319 | self.AtA = AtA |
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320 | |
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321 | |
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322 | def fit(self, point_coordinates_or_filename=None, z=None, |
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323 | verbose=False, |
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324 | point_origin=None, |
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325 | attribute_name=None, |
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326 | max_read_lines=500): |
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327 | """Fit a smooth surface to given 1d array of data points z. |
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328 | |
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329 | The smooth surface is computed at each vertex in the underlying |
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330 | mesh using the formula given in the module doc string. |
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331 | |
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332 | Inputs: |
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333 | point_coordinates: The co-ordinates of the data points. |
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334 | List of coordinate pairs [x, y] of |
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335 | data points or an nx2 Numeric array or a Geospatial_data object |
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336 | or points file filename |
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337 | z: Single 1d vector or array of data at the point_coordinates. |
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338 | |
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339 | """ |
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340 | |
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341 | # Use blocking to load in the point info |
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342 | if type(point_coordinates_or_filename) == types.StringType: |
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343 | msg = "Don't set a point origin when reading from a file" |
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344 | assert point_origin is None, msg |
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345 | filename = point_coordinates_or_filename |
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346 | |
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347 | G_data = Geospatial_data(filename, |
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348 | max_read_lines=max_read_lines, |
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349 | load_file_now=False, |
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350 | verbose=verbose) |
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351 | |
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352 | for i, geo_block in enumerate(G_data): |
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353 | if verbose is True and 0 == i%200: |
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354 | # The time this will take |
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355 | # is dependant on the # of Triangles |
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356 | |
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357 | print 'Processing Block %d' %i |
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358 | # FIXME (Ole): It would be good to say how many blocks |
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359 | # there are here. But this is no longer necessary |
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360 | # for pts files as they are reported in geospatial_data |
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361 | # I suggest deleting this verbose output and make |
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362 | # Geospatial_data more informative for txt files. |
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363 | # |
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364 | # I still think so (12/12/7, Ole). |
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365 | |
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366 | |
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367 | |
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368 | # Build the array |
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369 | |
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370 | points = geo_block.get_data_points(absolute=True) |
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371 | z = geo_block.get_attributes(attribute_name=attribute_name) |
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372 | self.build_fit_subset(points, z, verbose=verbose) |
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373 | |
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374 | |
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375 | point_coordinates = None |
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376 | else: |
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377 | point_coordinates = point_coordinates_or_filename |
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378 | |
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379 | if point_coordinates is None: |
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380 | if verbose: print 'Warning: no data points in fit' |
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381 | assert self.AtA <> None, 'no interpolation matrix' |
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382 | assert self.Atz <> None |
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383 | |
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384 | # FIXME (DSG) - do a message |
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385 | else: |
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386 | point_coordinates = ensure_absolute(point_coordinates, |
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387 | geo_reference=point_origin) |
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388 | # if isinstance(point_coordinates,Geospatial_data) and z is None: |
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389 | # z will come from the geo-ref |
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390 | self.build_fit_subset(point_coordinates, z, verbose) |
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391 | |
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392 | # Check sanity |
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393 | m = self.mesh.number_of_nodes # Nbr of basis functions (1/vertex) |
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394 | n = self.point_count |
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395 | if n<m and self.alpha == 0.0: |
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396 | msg = 'ERROR (least_squares): Too few data points\n' |
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397 | msg += 'There are only %d data points and alpha == 0. ' %n |
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398 | msg += 'Need at least %d\n' %m |
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399 | msg += 'Alternatively, set smoothing parameter alpha to a small ' |
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400 | msg += 'positive value,\ne.g. 1.0e-3.' |
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401 | raise TooFewPointsError(msg) |
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402 | |
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403 | self._build_coefficient_matrix_B(verbose) |
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404 | loners = self.mesh.get_lone_vertices() |
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405 | # FIXME - make this as error message. |
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406 | # test with |
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407 | # Not_yet_test_smooth_att_to_mesh_with_excess_verts. |
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408 | if len(loners)>0: |
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409 | msg = 'WARNING: (least_squares): \nVertices with no triangles\n' |
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410 | msg += 'All vertices should be part of a triangle.\n' |
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411 | msg += 'In the future this will be inforced.\n' |
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412 | msg += 'The following vertices are not part of a triangle;\n' |
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413 | msg += str(loners) |
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414 | print msg |
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415 | #raise VertsWithNoTrianglesError(msg) |
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416 | |
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417 | |
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418 | return conjugate_gradient(self.B, self.Atz, self.Atz, |
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419 | imax=2*len(self.Atz) ) |
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420 | |
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421 | |
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422 | def build_fit_subset(self, point_coordinates, z=None, attribute_name=None, |
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423 | verbose=False): |
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424 | """Fit a smooth surface to given 1d array of data points z. |
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425 | |
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426 | The smooth surface is computed at each vertex in the underlying |
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427 | mesh using the formula given in the module doc string. |
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428 | |
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429 | Inputs: |
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430 | point_coordinates: The co-ordinates of the data points. |
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431 | List of coordinate pairs [x, y] of |
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432 | data points or an nx2 Numeric array or a Geospatial_data object |
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433 | z: Single 1d vector or array of data at the point_coordinates. |
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434 | attribute_name: Used to get the z values from the |
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435 | geospatial object if no attribute_name is specified, |
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436 | it's a bit of a lucky dip as to what attributes you get. |
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437 | If there is only one attribute it will be that one. |
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438 | |
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439 | """ |
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440 | |
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441 | # FIXME(DSG-DSG): Check that the vert and point coords |
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442 | # have the same zone. |
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443 | if isinstance(point_coordinates,Geospatial_data): |
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444 | point_coordinates = point_coordinates.get_data_points( \ |
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445 | absolute = True) |
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446 | |
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447 | # Convert input to Numeric arrays |
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448 | if z is not None: |
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449 | z = ensure_numeric(z, num.Float) |
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450 | else: |
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451 | msg = 'z not specified' |
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452 | assert isinstance(point_coordinates,Geospatial_data), msg |
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453 | z = point_coordinates.get_attributes(attribute_name) |
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454 | |
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455 | point_coordinates = ensure_numeric(point_coordinates, num.Float) |
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456 | self._build_matrix_AtA_Atz(point_coordinates, z, verbose) |
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457 | |
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458 | |
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459 | ############################################################################ |
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460 | |
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461 | def fit_to_mesh(point_coordinates, # this can also be a points file name |
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462 | vertex_coordinates=None, |
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463 | triangles=None, |
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464 | mesh=None, |
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465 | point_attributes=None, |
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466 | alpha=DEFAULT_ALPHA, |
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467 | verbose=False, |
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468 | acceptable_overshoot=1.01, |
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469 | # FIXME: Move to config - this value is assumed in caching test |
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470 | # FIXME(Ole): Just realised that this was never implemented (29 Jan 2009). I suggest removing it altogether. |
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471 | mesh_origin=None, |
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472 | data_origin=None, |
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473 | max_read_lines=None, |
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474 | attribute_name=None, |
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475 | use_cache=False): |
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476 | """Wrapper around internal function _fit_to_mesh for use with caching. |
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477 | |
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478 | """ |
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479 | |
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480 | args = (point_coordinates, ) |
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481 | kwargs = {'vertex_coordinates': vertex_coordinates, |
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482 | 'triangles': triangles, |
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483 | 'mesh': mesh, |
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484 | 'point_attributes': point_attributes, |
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485 | 'alpha': alpha, |
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486 | 'verbose': verbose, |
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487 | 'acceptable_overshoot': acceptable_overshoot, |
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488 | 'mesh_origin': mesh_origin, |
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489 | 'data_origin': data_origin, |
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490 | 'max_read_lines': max_read_lines, |
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491 | 'attribute_name': attribute_name |
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492 | } |
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493 | |
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494 | if use_cache is True: |
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495 | if isinstance(point_coordinates, basestring): |
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496 | # We assume that point_coordinates is the name of a .csv/.txt |
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497 | # file which must be passed onto caching as a dependency |
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498 | # (in case it has changed on disk) |
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499 | dep = [point_coordinates] |
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500 | else: |
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501 | dep = None |
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502 | |
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503 | |
---|
504 | #from caching import myhash |
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505 | #import copy |
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506 | #print args |
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507 | #print kwargs |
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508 | #print 'hashing:' |
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509 | #print 'args', myhash( (args, kwargs) ) |
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510 | #print 'again', myhash( copy.deepcopy( (args, kwargs)) ) |
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511 | |
---|
512 | #print 'mesh hash', myhash( kwargs['mesh'] ) |
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513 | |
---|
514 | #print '-------------------------' |
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515 | #print 'vertices hash', myhash( kwargs['mesh'].nodes ) |
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516 | #print 'triangles hash', myhash( kwargs['mesh'].triangles ) |
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517 | #print '-------------------------' |
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518 | |
---|
519 | #for key in mesh.__dict__: |
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520 | # print key, myhash(mesh.__dict__[key]) |
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521 | |
---|
522 | #for key in mesh.quantities.keys(): |
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523 | # print key, myhash(mesh.quantities[key]) |
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524 | |
---|
525 | #import sys; sys.exit() |
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526 | |
---|
527 | return cache(_fit_to_mesh, |
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528 | args, kwargs, |
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529 | verbose=verbose, |
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530 | compression=False, |
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531 | dependencies=dep) |
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532 | else: |
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533 | return apply(_fit_to_mesh, |
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534 | args, kwargs) |
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535 | |
---|
536 | def _fit_to_mesh(point_coordinates, # this can also be a points file name |
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537 | vertex_coordinates=None, |
---|
538 | triangles=None, |
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539 | mesh=None, |
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540 | point_attributes=None, |
---|
541 | alpha=DEFAULT_ALPHA, |
---|
542 | verbose=False, |
---|
543 | acceptable_overshoot=1.01, |
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544 | mesh_origin=None, |
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545 | data_origin=None, |
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546 | max_read_lines=None, |
---|
547 | attribute_name=None): |
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548 | """ |
---|
549 | Fit a smooth surface to a triangulation, |
---|
550 | given data points with attributes. |
---|
551 | |
---|
552 | |
---|
553 | Inputs: |
---|
554 | vertex_coordinates: List of coordinate pairs [xi, eta] of |
---|
555 | points constituting a mesh (or an m x 2 Numeric array or |
---|
556 | a geospatial object) |
---|
557 | Points may appear multiple times |
---|
558 | (e.g. if vertices have discontinuities) |
---|
559 | |
---|
560 | triangles: List of 3-tuples (or a Numeric array) of |
---|
561 | integers representing indices of all vertices in the mesh. |
---|
562 | |
---|
563 | point_coordinates: List of coordinate pairs [x, y] of data points |
---|
564 | (or an nx2 Numeric array). This can also be a .csv/.txt/.pts |
---|
565 | file name. |
---|
566 | |
---|
567 | alpha: Smoothing parameter. |
---|
568 | |
---|
569 | acceptable overshoot: NOT IMPLEMENTED |
---|
570 | controls the allowed factor by which |
---|
571 | fitted values |
---|
572 | may exceed the value of input data. The lower limit is defined |
---|
573 | as min(z) - acceptable_overshoot*delta z and upper limit |
---|
574 | as max(z) + acceptable_overshoot*delta z |
---|
575 | |
---|
576 | |
---|
577 | mesh_origin: A geo_reference object or 3-tuples consisting of |
---|
578 | UTM zone, easting and northing. |
---|
579 | If specified vertex coordinates are assumed to be |
---|
580 | relative to their respective origins. |
---|
581 | |
---|
582 | |
---|
583 | point_attributes: Vector or array of data at the |
---|
584 | point_coordinates. |
---|
585 | |
---|
586 | """ |
---|
587 | |
---|
588 | if mesh is None: |
---|
589 | # FIXME(DSG): Throw errors if triangles or vertex_coordinates |
---|
590 | # are None |
---|
591 | |
---|
592 | #Convert input to Numeric arrays |
---|
593 | triangles = ensure_numeric(triangles, num.Int) |
---|
594 | vertex_coordinates = ensure_absolute(vertex_coordinates, |
---|
595 | geo_reference = mesh_origin) |
---|
596 | |
---|
597 | if verbose: print 'FitInterpolate: Building mesh' |
---|
598 | mesh = Mesh(vertex_coordinates, triangles) |
---|
599 | mesh.check_integrity() |
---|
600 | |
---|
601 | |
---|
602 | interp = Fit(mesh=mesh, |
---|
603 | verbose=verbose, |
---|
604 | alpha=alpha) |
---|
605 | |
---|
606 | vertex_attributes = interp.fit(point_coordinates, |
---|
607 | point_attributes, |
---|
608 | point_origin=data_origin, |
---|
609 | max_read_lines=max_read_lines, |
---|
610 | attribute_name=attribute_name, |
---|
611 | verbose=verbose) |
---|
612 | |
---|
613 | |
---|
614 | # Add the value checking stuff that's in least squares. |
---|
615 | # Maybe this stuff should get pushed down into Fit. |
---|
616 | # at least be a method of Fit. |
---|
617 | # Or intigrate it into the fit method, saving teh max and min's |
---|
618 | # as att's. |
---|
619 | |
---|
620 | return vertex_attributes |
---|
621 | |
---|
622 | |
---|
623 | #def _fit(*args, **kwargs): |
---|
624 | # """Private function for use with caching. Reason is that classes |
---|
625 | # may change their byte code between runs which is annoying. |
---|
626 | # """ |
---|
627 | # |
---|
628 | # return Fit(*args, **kwargs) |
---|
629 | |
---|
630 | |
---|
631 | def fit_to_mesh_file(mesh_file, point_file, mesh_output_file, |
---|
632 | alpha=DEFAULT_ALPHA, verbose= False, |
---|
633 | expand_search = False, |
---|
634 | precrop = False, |
---|
635 | display_errors = True): |
---|
636 | """ |
---|
637 | Given a mesh file (tsh) and a point attribute file, fit |
---|
638 | point attributes to the mesh and write a mesh file with the |
---|
639 | results. |
---|
640 | |
---|
641 | Note: the points file needs titles. If you want anuga to use the tsh file, |
---|
642 | make sure the title is elevation. |
---|
643 | |
---|
644 | NOTE: Throws IOErrors, for a variety of file problems. |
---|
645 | |
---|
646 | """ |
---|
647 | |
---|
648 | from load_mesh.loadASCII import import_mesh_file, \ |
---|
649 | export_mesh_file, concatinate_attributelist |
---|
650 | |
---|
651 | |
---|
652 | try: |
---|
653 | mesh_dict = import_mesh_file(mesh_file) |
---|
654 | except IOError,e: |
---|
655 | if display_errors: |
---|
656 | print "Could not load bad file. ", e |
---|
657 | raise IOError #Could not load bad mesh file. |
---|
658 | |
---|
659 | vertex_coordinates = mesh_dict['vertices'] |
---|
660 | triangles = mesh_dict['triangles'] |
---|
661 | if type(mesh_dict['vertex_attributes']) == num.ArrayType: |
---|
662 | old_point_attributes = mesh_dict['vertex_attributes'].tolist() |
---|
663 | else: |
---|
664 | old_point_attributes = mesh_dict['vertex_attributes'] |
---|
665 | |
---|
666 | if type(mesh_dict['vertex_attribute_titles']) == num.ArrayType: |
---|
667 | old_title_list = mesh_dict['vertex_attribute_titles'].tolist() |
---|
668 | else: |
---|
669 | old_title_list = mesh_dict['vertex_attribute_titles'] |
---|
670 | |
---|
671 | if verbose: print 'tsh file %s loaded' %mesh_file |
---|
672 | |
---|
673 | # load in the points file |
---|
674 | try: |
---|
675 | geo = Geospatial_data(point_file, verbose=verbose) |
---|
676 | except IOError,e: |
---|
677 | if display_errors: |
---|
678 | print "Could not load bad file. ", e |
---|
679 | raise IOError #Re-raise exception |
---|
680 | |
---|
681 | point_coordinates = geo.get_data_points(absolute=True) |
---|
682 | title_list,point_attributes = concatinate_attributelist( \ |
---|
683 | geo.get_all_attributes()) |
---|
684 | |
---|
685 | if mesh_dict.has_key('geo_reference') and \ |
---|
686 | not mesh_dict['geo_reference'] is None: |
---|
687 | mesh_origin = mesh_dict['geo_reference'].get_origin() |
---|
688 | else: |
---|
689 | mesh_origin = None |
---|
690 | |
---|
691 | if verbose: print "points file loaded" |
---|
692 | if verbose: print "fitting to mesh" |
---|
693 | f = fit_to_mesh(point_coordinates, |
---|
694 | vertex_coordinates, |
---|
695 | triangles, |
---|
696 | None, |
---|
697 | point_attributes, |
---|
698 | alpha = alpha, |
---|
699 | verbose = verbose, |
---|
700 | data_origin = None, |
---|
701 | mesh_origin = mesh_origin) |
---|
702 | if verbose: print "finished fitting to mesh" |
---|
703 | |
---|
704 | # convert array to list of lists |
---|
705 | new_point_attributes = f.tolist() |
---|
706 | #FIXME have this overwrite attributes with the same title - DSG |
---|
707 | #Put the newer attributes last |
---|
708 | if old_title_list <> []: |
---|
709 | old_title_list.extend(title_list) |
---|
710 | #FIXME can this be done a faster way? - DSG |
---|
711 | for i in range(len(old_point_attributes)): |
---|
712 | old_point_attributes[i].extend(new_point_attributes[i]) |
---|
713 | mesh_dict['vertex_attributes'] = old_point_attributes |
---|
714 | mesh_dict['vertex_attribute_titles'] = old_title_list |
---|
715 | else: |
---|
716 | mesh_dict['vertex_attributes'] = new_point_attributes |
---|
717 | mesh_dict['vertex_attribute_titles'] = title_list |
---|
718 | |
---|
719 | if verbose: print "exporting to file ", mesh_output_file |
---|
720 | |
---|
721 | try: |
---|
722 | export_mesh_file(mesh_output_file, mesh_dict) |
---|
723 | except IOError,e: |
---|
724 | if display_errors: |
---|
725 | print "Could not write file. ", e |
---|
726 | raise IOError |
---|