1 | """ |
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2 | Sasview model constructor. |
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3 | |
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4 | Given a module defining an OpenCL kernel such as sasmodels.models.cylinder, |
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5 | create a sasview model class to run that kernel as follows:: |
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6 | |
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7 | from sasmodels.sasview_model import make_class |
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8 | from sasmodels.models import cylinder |
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9 | CylinderModel = make_class(cylinder, dtype='single') |
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10 | |
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11 | The model parameters for sasmodels are different from those in sasview. |
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12 | When reloading previously saved models, the parameters should be converted |
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13 | using :func:`sasmodels.convert.convert`. |
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14 | """ |
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15 | from __future__ import print_function |
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16 | |
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17 | import math |
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18 | from copy import deepcopy |
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19 | import collections |
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20 | import traceback |
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21 | import logging |
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22 | |
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23 | import numpy as np |
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24 | |
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25 | from . import core |
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26 | from . import custom |
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27 | from . import generate |
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28 | |
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29 | try: |
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30 | from typing import Dict, Mapping, Any, Sequence, Tuple, NamedTuple, List, Optional |
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31 | from .kernel import KernelModel |
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32 | MultiplicityInfoType = NamedTuple( |
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33 | 'MuliplicityInfo', |
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34 | [("number", int), ("control", str), ("choices", List[str]), |
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35 | ("x_axis_label", str)]) |
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36 | except ImportError: |
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37 | pass |
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38 | |
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39 | # TODO: separate x_axis_label from multiplicity info |
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40 | # The x-axis label belongs with the profile generating function |
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41 | MultiplicityInfo = collections.namedtuple( |
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42 | 'MultiplicityInfo', |
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43 | ["number", "control", "choices", "x_axis_label"], |
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44 | ) |
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45 | |
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46 | def load_standard_models(): |
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47 | """ |
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48 | Load and return the list of predefined models. |
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49 | |
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50 | If there is an error loading a model, then a traceback is logged and the |
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51 | model is not returned. |
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52 | """ |
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53 | models = [] |
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54 | for name in core.list_models(): |
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55 | try: |
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56 | models.append(_make_standard_model(name)) |
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57 | except: |
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58 | logging.error(traceback.format_exc()) |
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59 | return models |
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60 | |
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61 | |
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62 | def load_custom_model(path): |
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63 | """ |
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64 | Load a custom model given the model path. |
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65 | """ |
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66 | kernel_module = custom.load_custom_kernel_module(path) |
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67 | model_info = generate.make_model_info(kernel_module) |
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68 | return _make_model_from_info(model_info) |
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69 | |
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70 | |
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71 | def _make_standard_model(name): |
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72 | """ |
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73 | Load the sasview model defined by *name*. |
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74 | |
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75 | *name* can be a standard model name or a path to a custom model. |
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76 | |
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77 | Returns a class that can be used directly as a sasview model. |
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78 | """ |
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79 | kernel_module = generate.load_kernel_module(name) |
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80 | model_info = generate.make_model_info(kernel_module) |
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81 | return _make_model_from_info(model_info) |
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82 | |
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83 | |
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84 | def _make_model_from_info(model_info): |
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85 | """ |
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86 | Convert *model_info* into a SasView model wrapper. |
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87 | """ |
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88 | model_info['variant_info'] = None # temporary hack for older sasview |
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89 | def __init__(self, multiplicity=1): |
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90 | SasviewModel.__init__(self, multiplicity=multiplicity) |
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91 | attrs = _generate_model_attributes(model_info) |
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92 | attrs['__init__'] = __init__ |
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93 | ConstructedModel = type(model_info['id'], (SasviewModel,), attrs) |
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94 | return ConstructedModel |
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95 | |
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96 | def _generate_model_attributes(model_info): |
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97 | # type: (ModelInfo) -> Dict[str, Any] |
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98 | """ |
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99 | Generate the class attributes for the model. |
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100 | |
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101 | This should include all the information necessary to query the model |
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102 | details so that you do not need to instantiate a model to query it. |
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103 | |
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104 | All the attributes should be immutable to avoid accidents. |
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105 | """ |
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106 | attrs = {} # type: Dict[str, Any] |
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107 | attrs['_model_info'] = model_info |
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108 | attrs['name'] = model_info['name'] |
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109 | attrs['id'] = model_info['id'] |
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110 | attrs['description'] = model_info['description'] |
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111 | attrs['category'] = model_info['category'] |
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112 | |
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113 | # TODO: allow model to override axis labels input/output name/unit |
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114 | |
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115 | #self.is_multifunc = False |
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116 | non_fittable = [] # type: List[str] |
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117 | variants = MultiplicityInfo(0, "", [], "") |
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118 | attrs['is_structure_factor'] = model_info['structure_factor'] |
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119 | attrs['is_form_factor'] = model_info['ER'] is not None |
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120 | attrs['is_multiplicity_model'] = variants[0] > 1 |
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121 | attrs['multiplicity_info'] = variants |
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122 | |
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123 | partype = model_info['partype'] |
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124 | orientation_params = ( |
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125 | partype['orientation'] |
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126 | + [n + '.width' for n in partype['orientation']] |
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127 | + partype['magnetic']) |
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128 | magnetic_params = partype['magnetic'] |
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129 | fixed = [n + '.width' for n in partype['pd-2d']] |
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130 | |
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131 | attrs['orientation_params'] = tuple(orientation_params) |
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132 | attrs['magnetic_params'] = tuple(magnetic_params) |
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133 | attrs['fixed'] = tuple(fixed) |
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134 | |
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135 | attrs['non_fittable'] = tuple(non_fittable) |
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136 | |
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137 | return attrs |
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138 | |
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139 | class SasviewModel(object): |
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140 | """ |
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141 | Sasview wrapper for opencl/ctypes model. |
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142 | """ |
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143 | # Model parameters for the specific model are set in the class constructor |
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144 | # via the _generate_model_attributes function, which subclasses |
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145 | # SasviewModel. They are included here for typing and documentation |
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146 | # purposes. |
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147 | _model = None # type: KernelModel |
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148 | _model_info = None # type: ModelInfo |
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149 | #: load/save name for the model |
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150 | id = None # type: str |
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151 | #: display name for the model |
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152 | name = None # type: str |
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153 | #: short model description |
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154 | description = None # type: str |
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155 | #: default model category |
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156 | category = None # type: str |
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157 | |
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158 | #: names of the orientation parameters in the order they appear |
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159 | orientation_params = None # type: Sequence[str] |
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160 | #: names of the magnetic parameters in the order they appear |
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161 | magnetic_params = None # type: Sequence[str] |
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162 | #: names of the fittable parameters |
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163 | fixed = None # type: Sequence[str] |
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164 | # TODO: the attribute fixed is ill-named |
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165 | |
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166 | # Axis labels |
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167 | input_name = "Q" |
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168 | input_unit = "A^{-1}" |
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169 | output_name = "Intensity" |
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170 | output_unit = "cm^{-1}" |
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171 | |
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172 | #: default cutoff for polydispersity |
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173 | cutoff = 1e-5 |
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174 | |
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175 | # Note: Use non-mutable values for class attributes to avoid errors |
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176 | #: parameters that are not fitted |
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177 | non_fittable = () # type: Sequence[str] |
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178 | |
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179 | #: True if model should appear as a structure factor |
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180 | is_structure_factor = False |
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181 | #: True if model should appear as a form factor |
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182 | is_form_factor = False |
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183 | #: True if model has multiplicity |
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184 | is_multiplicity_model = False |
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185 | #: Mulitplicity information |
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186 | multiplicity_info = None # type: MultiplicityInfoType |
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187 | |
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188 | # Per-instance variables |
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189 | #: parameter {name: value} mapping |
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190 | params = None # type: Dict[str, float] |
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191 | #: values for dispersion width, npts, nsigmas and type |
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192 | dispersion = None # type: Dict[str, Any] |
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193 | #: units and limits for each parameter |
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194 | details = None # type: Mapping[str, Tuple(str, float, float)] |
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195 | #: multiplicity used, or None if no multiplicity controls |
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196 | multiplicity = None # type: Optional[int] |
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197 | |
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198 | def __init__(self, multiplicity): |
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199 | # type: () -> None |
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200 | #print("initializing", self.name) |
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201 | #raise Exception("first initialization") |
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202 | self._model = None |
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203 | |
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204 | ## _persistency_dict is used by sas.perspectives.fitting.basepage |
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205 | ## to store dispersity reference. |
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206 | self._persistency_dict = {} |
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207 | |
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208 | self.multiplicity = multiplicity |
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209 | |
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210 | self.params = collections.OrderedDict() |
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211 | self.dispersion = {} |
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212 | self.details = {} |
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213 | |
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214 | for p in self._model_info['parameters']: |
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215 | self.params[p.name] = p.default |
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216 | self.details[p.name] = [p.units] + p.limits |
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217 | |
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218 | for name in self._model_info['partype']['pd-2d']: |
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219 | self.dispersion[name] = { |
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220 | 'width': 0, |
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221 | 'npts': 35, |
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222 | 'nsigmas': 3, |
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223 | 'type': 'gaussian', |
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224 | } |
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225 | |
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226 | def __get_state__(self): |
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227 | state = self.__dict__.copy() |
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228 | state.pop('_model') |
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229 | # May need to reload model info on set state since it has pointers |
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230 | # to python implementations of Iq, etc. |
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231 | #state.pop('_model_info') |
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232 | return state |
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233 | |
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234 | def __set_state__(self, state): |
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235 | self.__dict__ = state |
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236 | self._model = None |
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237 | |
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238 | def __str__(self): |
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239 | """ |
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240 | :return: string representation |
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241 | """ |
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242 | return self.name |
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243 | |
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244 | def is_fittable(self, par_name): |
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245 | """ |
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246 | Check if a given parameter is fittable or not |
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247 | |
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248 | :param par_name: the parameter name to check |
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249 | """ |
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250 | return par_name.lower() in self.fixed |
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251 | #For the future |
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252 | #return self.params[str(par_name)].is_fittable() |
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253 | |
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254 | |
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255 | # pylint: disable=no-self-use |
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256 | def getProfile(self): |
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257 | """ |
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258 | Get SLD profile |
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259 | |
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260 | : return: (z, beta) where z is a list of depth of the transition points |
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261 | beta is a list of the corresponding SLD values |
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262 | """ |
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263 | return None, None |
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264 | |
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265 | def setParam(self, name, value): |
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266 | """ |
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267 | Set the value of a model parameter |
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268 | |
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269 | :param name: name of the parameter |
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270 | :param value: value of the parameter |
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271 | |
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272 | """ |
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273 | # Look for dispersion parameters |
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274 | toks = name.split('.') |
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275 | if len(toks) == 2: |
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276 | for item in self.dispersion.keys(): |
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277 | if item.lower() == toks[0].lower(): |
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278 | for par in self.dispersion[item]: |
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279 | if par.lower() == toks[1].lower(): |
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280 | self.dispersion[item][par] = value |
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281 | return |
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282 | else: |
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283 | # Look for standard parameter |
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284 | for item in self.params.keys(): |
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285 | if item.lower() == name.lower(): |
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286 | self.params[item] = value |
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287 | return |
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288 | |
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289 | raise ValueError("Model does not contain parameter %s" % name) |
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290 | |
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291 | def getParam(self, name): |
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292 | """ |
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293 | Set the value of a model parameter |
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294 | |
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295 | :param name: name of the parameter |
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296 | |
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297 | """ |
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298 | # Look for dispersion parameters |
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299 | toks = name.split('.') |
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300 | if len(toks) == 2: |
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301 | for item in self.dispersion.keys(): |
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302 | if item.lower() == toks[0].lower(): |
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303 | for par in self.dispersion[item]: |
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304 | if par.lower() == toks[1].lower(): |
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305 | return self.dispersion[item][par] |
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306 | else: |
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307 | # Look for standard parameter |
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308 | for item in self.params.keys(): |
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309 | if item.lower() == name.lower(): |
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310 | return self.params[item] |
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311 | |
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312 | raise ValueError("Model does not contain parameter %s" % name) |
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313 | |
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314 | def getParamList(self): |
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315 | """ |
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316 | Return a list of all available parameters for the model |
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317 | """ |
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318 | param_list = self.params.keys() |
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319 | # WARNING: Extending the list with the dispersion parameters |
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320 | param_list.extend(self.getDispParamList()) |
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321 | return param_list |
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322 | |
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323 | def getDispParamList(self): |
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324 | """ |
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325 | Return a list of polydispersity parameters for the model |
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326 | """ |
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327 | # TODO: fix test so that parameter order doesn't matter |
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328 | ret = ['%s.%s' % (d.lower(), p) |
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329 | for d in self._model_info['partype']['pd-2d'] |
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330 | for p in ('npts', 'nsigmas', 'width')] |
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331 | #print(ret) |
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332 | return ret |
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333 | |
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334 | def clone(self): |
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335 | """ Return a identical copy of self """ |
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336 | return deepcopy(self) |
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337 | |
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338 | def run(self, x=0.0): |
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339 | """ |
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340 | Evaluate the model |
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341 | |
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342 | :param x: input q, or [q,phi] |
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343 | |
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344 | :return: scattering function P(q) |
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345 | |
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346 | **DEPRECATED**: use calculate_Iq instead |
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347 | """ |
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348 | if isinstance(x, (list, tuple)): |
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349 | # pylint: disable=unpacking-non-sequence |
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350 | q, phi = x |
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351 | return self.calculate_Iq([q * math.cos(phi)], |
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352 | [q * math.sin(phi)])[0] |
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353 | else: |
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354 | return self.calculate_Iq([float(x)])[0] |
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355 | |
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356 | |
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357 | def runXY(self, x=0.0): |
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358 | """ |
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359 | Evaluate the model in cartesian coordinates |
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360 | |
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361 | :param x: input q, or [qx, qy] |
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362 | |
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363 | :return: scattering function P(q) |
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364 | |
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365 | **DEPRECATED**: use calculate_Iq instead |
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366 | """ |
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367 | if isinstance(x, (list, tuple)): |
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368 | return self.calculate_Iq([float(x[0])], [float(x[1])])[0] |
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369 | else: |
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370 | return self.calculate_Iq([float(x)])[0] |
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371 | |
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372 | def evalDistribution(self, qdist): |
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373 | r""" |
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374 | Evaluate a distribution of q-values. |
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375 | |
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376 | :param qdist: array of q or a list of arrays [qx,qy] |
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377 | |
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378 | * For 1D, a numpy array is expected as input |
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379 | |
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380 | :: |
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381 | |
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382 | evalDistribution(q) |
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383 | |
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384 | where *q* is a numpy array. |
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385 | |
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386 | * For 2D, a list of *[qx,qy]* is expected with 1D arrays as input |
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387 | |
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388 | :: |
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389 | |
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390 | qx = [ qx[0], qx[1], qx[2], ....] |
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391 | qy = [ qy[0], qy[1], qy[2], ....] |
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392 | |
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393 | If the model is 1D only, then |
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394 | |
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395 | .. math:: |
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396 | |
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397 | q = \sqrt{q_x^2+q_y^2} |
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398 | |
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399 | """ |
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400 | if isinstance(qdist, (list, tuple)): |
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401 | # Check whether we have a list of ndarrays [qx,qy] |
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402 | qx, qy = qdist |
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403 | partype = self._model_info['partype'] |
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404 | if not partype['orientation'] and not partype['magnetic']: |
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405 | return self.calculate_Iq(np.sqrt(qx ** 2 + qy ** 2)) |
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406 | else: |
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407 | return self.calculate_Iq(qx, qy) |
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408 | |
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409 | elif isinstance(qdist, np.ndarray): |
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410 | # We have a simple 1D distribution of q-values |
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411 | return self.calculate_Iq(qdist) |
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412 | |
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413 | else: |
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414 | raise TypeError("evalDistribution expects q or [qx, qy], not %r" |
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415 | % type(qdist)) |
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416 | |
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417 | def calculate_Iq(self, *args): |
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418 | """ |
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419 | Calculate Iq for one set of q with the current parameters. |
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420 | |
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421 | If the model is 1D, use *q*. If 2D, use *qx*, *qy*. |
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422 | |
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423 | This should NOT be used for fitting since it copies the *q* vectors |
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424 | to the card for each evaluation. |
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425 | """ |
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426 | if self._model is None: |
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427 | self._model = core.build_model(self._model_info) |
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428 | q_vectors = [np.asarray(q) for q in args] |
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429 | fn = self._model.make_kernel(q_vectors) |
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430 | pars = [self.params[v] for v in fn.fixed_pars] |
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431 | pd_pars = [self._get_weights(p) for p in fn.pd_pars] |
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432 | result = fn(pars, pd_pars, self.cutoff) |
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433 | fn.q_input.release() |
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434 | fn.release() |
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435 | return result |
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436 | |
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437 | def calculate_ER(self): |
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438 | """ |
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439 | Calculate the effective radius for P(q)*S(q) |
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440 | |
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441 | :return: the value of the effective radius |
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442 | """ |
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443 | ER = self._model_info.get('ER', None) |
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444 | if ER is None: |
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445 | return 1.0 |
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446 | else: |
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447 | values, weights = self._dispersion_mesh() |
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448 | fv = ER(*values) |
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449 | #print(values[0].shape, weights.shape, fv.shape) |
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450 | return np.sum(weights * fv) / np.sum(weights) |
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451 | |
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452 | def calculate_VR(self): |
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453 | """ |
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454 | Calculate the volf ratio for P(q)*S(q) |
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455 | |
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456 | :return: the value of the volf ratio |
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457 | """ |
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458 | VR = self._model_info.get('VR', None) |
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459 | if VR is None: |
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460 | return 1.0 |
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461 | else: |
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462 | values, weights = self._dispersion_mesh() |
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463 | whole, part = VR(*values) |
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464 | return np.sum(weights * part) / np.sum(weights * whole) |
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465 | |
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466 | def set_dispersion(self, parameter, dispersion): |
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467 | """ |
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468 | Set the dispersion object for a model parameter |
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469 | |
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470 | :param parameter: name of the parameter [string] |
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471 | :param dispersion: dispersion object of type Dispersion |
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472 | """ |
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473 | if parameter.lower() in (s.lower() for s in self.params.keys()): |
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474 | # TODO: Store the disperser object directly in the model. |
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475 | # The current method of creating one on the fly whenever it is |
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476 | # needed is kind of funky. |
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477 | # Note: can't seem to get disperser parameters from sasview |
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478 | # (1) Could create a sasview model that has not yet # been |
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479 | # converted, assign the disperser to one of its polydisperse |
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480 | # parameters, then retrieve the disperser parameters from the |
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481 | # sasview model. (2) Could write a disperser parameter retriever |
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482 | # in sasview. (3) Could modify sasview to use sasmodels.weights |
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483 | # dispersers. |
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484 | # For now, rely on the fact that the sasview only ever uses |
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485 | # new dispersers in the set_dispersion call and create a new |
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486 | # one instead of trying to assign parameters. |
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487 | from . import weights |
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488 | disperser = weights.dispersers[dispersion.__class__.__name__] |
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489 | dispersion = weights.models[disperser]() |
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490 | self.dispersion[parameter] = dispersion.get_pars() |
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491 | else: |
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492 | raise ValueError("%r is not a dispersity or orientation parameter") |
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493 | |
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494 | def _dispersion_mesh(self): |
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495 | """ |
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496 | Create a mesh grid of dispersion parameters and weights. |
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497 | |
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498 | Returns [p1,p2,...],w where pj is a vector of values for parameter j |
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499 | and w is a vector containing the products for weights for each |
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500 | parameter set in the vector. |
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501 | """ |
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502 | pars = self._model_info['partype']['volume'] |
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503 | return core.dispersion_mesh([self._get_weights(p) for p in pars]) |
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504 | |
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505 | def _get_weights(self, par): |
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506 | """ |
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507 | Return dispersion weights for parameter |
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508 | """ |
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509 | from . import weights |
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510 | relative = self._model_info['partype']['pd-rel'] |
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511 | limits = self._model_info['limits'] |
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512 | dis = self.dispersion[par] |
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513 | value, weight = weights.get_weights( |
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514 | dis['type'], dis['npts'], dis['width'], dis['nsigmas'], |
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515 | self.params[par], limits[par], par in relative) |
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516 | return value, weight / np.sum(weight) |
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517 | |
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518 | |
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519 | def test_model(): |
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520 | """ |
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521 | Test that a sasview model (cylinder) can be run. |
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522 | """ |
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523 | Cylinder = _make_standard_model('cylinder') |
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524 | cylinder = Cylinder() |
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525 | return cylinder.evalDistribution([0.1,0.1]) |
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526 | |
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527 | |
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528 | def test_model_list(): |
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529 | """ |
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530 | Make sure that all models build as sasview models. |
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531 | """ |
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532 | from .exception import annotate_exception |
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533 | for name in core.list_models(): |
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534 | try: |
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535 | _make_standard_model(name) |
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536 | except: |
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537 | annotate_exception("when loading "+name) |
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538 | raise |
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539 | |
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540 | if __name__ == "__main__": |
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541 | print("cylinder(0.1,0.1)=%g"%test_model()) |
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