source: sasmodels/sasmodels/product.py @ 8f04da4

core_shell_microgelscostrafo411magnetic_modelticket-1257-vesicle-productticket_1156ticket_1265_superballticket_822_more_unit_tests
Last change on this file since 8f04da4 was 8f04da4, checked in by Paul Kienzle <pkienzle@…>, 7 years ago

tuned random model generation for more models

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Line 
1"""
2Product model
3-------------
4
5The product model multiplies the structure factor by the form factor,
6modulated by the effective radius of the form.  The resulting model
7has a attributes of both the model description (with parameters, etc.)
8and the module evaluator (with call, release, etc.).
9
10To use it, first load form factor P and structure factor S, then create
11*make_product_info(P, S)*.
12"""
13from __future__ import print_function, division
14
15from copy import copy
16import numpy as np  # type: ignore
17
18from .modelinfo import Parameter, ParameterTable, ModelInfo
19from .kernel import KernelModel, Kernel
20from .details import make_details, dispersion_mesh
21
22try:
23    from typing import Tuple
24except ImportError:
25    pass
26
27# TODO: make estimates available to constraints
28#ESTIMATED_PARAMETERS = [
29#    ["est_radius_effective", "A", 0.0, [0, np.inf], "", "Estimated effective radius"],
30#    ["est_volume_ratio", "", 1.0, [0, np.inf], "", "Estimated volume ratio"],
31#]
32
33ER_ID = "radius_effective"
34VF_ID = "volfraction"
35
36# TODO: core_shell_sphere model has suppressed the volume ratio calculation
37# revert it after making VR and ER available at run time as constraints.
38def make_product_info(p_info, s_info):
39    # type: (ModelInfo, ModelInfo) -> ModelInfo
40    """
41    Create info block for product model.
42    """
43    # Make sure effective radius is the first parameter and
44    # make sure volume fraction is the second parameter of the
45    # structure factor calculator.  Structure factors should not
46    # have any magnetic parameters
47    if not s_info.parameters.kernel_parameters[0].id == ER_ID:
48        raise TypeError("S needs %s as first parameter"%ER_ID)
49    if not s_info.parameters.kernel_parameters[1].id == VF_ID:
50        raise TypeError("S needs %s as second parameter"%VF_ID)
51    if not s_info.parameters.magnetism_index == []:
52        raise TypeError("S should not have SLD parameters")
53    p_id, p_name, p_pars = p_info.id, p_info.name, p_info.parameters
54    s_id, s_name, s_pars = s_info.id, s_info.name, s_info.parameters
55
56    # Create list of parameters for the combined model.  Skip the first
57    # parameter of S, which we verified above is effective radius.  If there
58    # are any names in P that overlap with those in S, modify the name in S
59    # to distinguish it.
60    p_set = set(p.id for p in p_pars.kernel_parameters)
61    s_list = [(_tag_parameter(par) if par.id in p_set else par)
62              for par in s_pars.kernel_parameters[1:]]
63    # Check if still a collision after renaming.  This could happen if for
64    # example S has volfrac and P has both volfrac and volfrac_S.
65    if any(p.id in p_set for p in s_list):
66        raise TypeError("name collision: P has P.name and P.name_S while S has S.name")
67
68    translate_name = dict((old.id, new.id) for old, new
69                          in zip(s_pars.kernel_parameters[1:], s_list))
70    demo = {}
71    demo.update(p_info.demo.items())
72    demo.update((translate_name[k], v) for k, v in s_info.demo.items()
73                if k not in ("background", "scale") and not k.startswith(ER_ID))
74    combined_pars = p_pars.kernel_parameters + s_list
75    parameters = ParameterTable(combined_pars)
76    parameters.max_pd = p_pars.max_pd + s_pars.max_pd
77
78    model_info = ModelInfo()
79    model_info.id = '*'.join((p_id, s_id))
80    model_info.name = '*'.join((p_name, s_name))
81    model_info.filename = None
82    model_info.title = 'Product of %s and %s'%(p_name, s_name)
83    model_info.description = model_info.title
84    model_info.docs = model_info.title
85    model_info.category = "custom"
86    model_info.parameters = parameters
87    #model_info.single = p_info.single and s_info.single
88    model_info.structure_factor = False
89    model_info.variant_info = None
90    #model_info.tests = []
91    #model_info.source = []
92    # Iq, Iqxy, form_volume, ER, VR and sesans
93    # Remember the component info blocks so we can build the model
94    model_info.composition = ('product', [p_info, s_info])
95    # TODO: delegate random to p_info, s_info
96    #model_info.random = lambda: {}
97    model_info.demo = demo
98
99    ## Show the parameter table with the demo values
100    #from .compare import get_pars, parlist
101    #print("==== %s ====="%model_info.name)
102    #values = get_pars(model_info, use_demo=True)
103    #print(parlist(model_info, values, is2d=True))
104    return model_info
105
106def _tag_parameter(par):
107    """
108    Tag the parameter name with _S to indicate that the parameter comes from
109    the structure factor parameter set.  This is only necessary if the
110    form factor model includes a parameter of the same name as a parameter
111    in the structure factor.
112    """
113    par = copy(par)
114    # Protect against a vector parameter in S by appending the vector length
115    # to the renamed parameter.  Note: haven't tested this since no existing
116    # structure factor models contain vector parameters.
117    vector_length = par.name[len(par.id):]
118    par.id = par.id + "_S"
119    par.name = par.id + vector_length
120    return par
121
122class ProductModel(KernelModel):
123    def __init__(self, model_info, P, S):
124        # type: (ModelInfo, KernelModel, KernelModel) -> None
125        self.info = model_info
126        self.P = P
127        self.S = S
128
129    def make_kernel(self, q_vectors):
130        # type: (List[np.ndarray]) -> Kernel
131        # Note: may be sending the q_vectors to the GPU twice even though they
132        # are only needed once.  It would mess up modularity quite a bit to
133        # handle this optimally, especially since there are many cases where
134        # separate q vectors are needed (e.g., form in python and structure
135        # in opencl; or both in opencl, but one in single precision and the
136        # other in double precision).
137        p_kernel = self.P.make_kernel(q_vectors)
138        s_kernel = self.S.make_kernel(q_vectors)
139        return ProductKernel(self.info, p_kernel, s_kernel)
140
141    def release(self):
142        # type: (None) -> None
143        """
144        Free resources associated with the model.
145        """
146        self.P.release()
147        self.S.release()
148
149
150class ProductKernel(Kernel):
151    def __init__(self, model_info, p_kernel, s_kernel):
152        # type: (ModelInfo, Kernel, Kernel) -> None
153        self.info = model_info
154        self.p_kernel = p_kernel
155        self.s_kernel = s_kernel
156        self.dtype = p_kernel.dtype
157        self.results = []  # type: List[np.ndarray]
158
159    def __call__(self, call_details, values, cutoff, magnetic):
160        # type: (CallDetails, np.ndarray, float, bool) -> np.ndarray
161        p_info, s_info = self.info.composition[1]
162
163        # if there are magnetic parameters, they will only be on the
164        # form factor P, not the structure factor S.
165        nmagnetic = len(self.info.parameters.magnetism_index)
166        if nmagnetic:
167            spin_index = self.info.parameters.npars + 2
168            magnetism = values[spin_index: spin_index+3+3*nmagnetic]
169        else:
170            magnetism = []
171        nvalues = self.info.parameters.nvalues
172        nweights = call_details.num_weights
173        weights = values[nvalues:nvalues + 2*nweights]
174
175        # Construct the calling parameters for P.
176        p_npars = p_info.parameters.npars
177        p_length = call_details.length[:p_npars]
178        p_offset = call_details.offset[:p_npars]
179        p_details = make_details(p_info, p_length, p_offset, nweights)
180        # Set p scale to the volume fraction in s, which is the first of the
181        # 'S' parameters in the parameter list, or 2+np in 0-origin.
182        volfrac = values[2+p_npars]
183        p_values = [[volfrac, 0.0], values[2:2+p_npars], magnetism, weights]
184        spacer = (32 - sum(len(v) for v in p_values)%32)%32
185        p_values.append([0.]*spacer)
186        p_values = np.hstack(p_values).astype(self.p_kernel.dtype)
187
188        # Call ER and VR for P since these are needed for S.
189        p_er, p_vr = calc_er_vr(p_info, p_details, p_values)
190        s_vr = (volfrac/p_vr if p_vr != 0. else volfrac)
191        #print("volfrac:%g p_er:%g p_vr:%g s_vr:%g"%(volfrac,p_er,p_vr,s_vr))
192
193        # Construct the calling parameters for S.
194        # The  effective radius is not in the combined parameter list, so
195        # the number of 'S' parameters is one less than expected.  The
196        # computed effective radius needs to be added into the weights
197        # vector, especially since it is a polydisperse parameter in the
198        # stand-alone structure factor models.  We will added it at the
199        # end so the remaining offsets don't need to change.
200        s_npars = s_info.parameters.npars-1
201        s_length = call_details.length[p_npars:p_npars+s_npars]
202        s_offset = call_details.offset[p_npars:p_npars+s_npars]
203        s_length = np.hstack((1, s_length))
204        s_offset = np.hstack((nweights, s_offset))
205        s_details = make_details(s_info, s_length, s_offset, nweights+1)
206        v, w = weights[:nweights], weights[nweights:]
207        s_values = [
208            # scale=1, background=0, radius_effective=p_er, volfraction=s_vr
209            [1., 0., p_er, s_vr],
210            # structure factor parameters start after scale, background and
211            # all the form factor parameters.  Skip the volfraction parameter
212            # as well, since it is computed elsewhere, and go to the end of the
213            # parameter list.
214            values[2+p_npars+1:2+p_npars+s_npars],
215            # no magnetism parameters to include for S
216            # add er into the (value, weights) pairs
217            v, [p_er], w, [1.0]
218        ]
219        spacer = (32 - sum(len(v) for v in s_values)%32)%32
220        s_values.append([0.]*spacer)
221        s_values = np.hstack(s_values).astype(self.s_kernel.dtype)
222
223        # Call the kernels
224        p_result = self.p_kernel(p_details, p_values, cutoff, magnetic)
225        s_result = self.s_kernel(s_details, s_values, cutoff, False)
226
227        #print("p_npars",p_npars,s_npars,p_er,s_vr,values[2+p_npars+1:2+p_npars+s_npars])
228        #call_details.show(values)
229        #print("values", values)
230        #p_details.show(p_values)
231        #print("=>", p_result)
232        #s_details.show(s_values)
233        #print("=>", s_result)
234
235        # remember the parts for plotting later
236        self.results = [p_result, s_result]
237
238        #import pylab as plt
239        #plt.subplot(211); plt.loglog(self.p_kernel.q_input.q, p_result, '-')
240        #plt.subplot(212); plt.loglog(self.s_kernel.q_input.q, s_result, '-')
241        #plt.figure()
242
243        return values[0]*(p_result*s_result) + values[1]
244
245    def release(self):
246        # type: () -> None
247        self.p_kernel.release()
248        self.s_kernel.release()
249
250
251def calc_er_vr(model_info, call_details, values):
252    # type: (ModelInfo, ParameterSet) -> Tuple[float, float]
253
254    if model_info.ER is None and model_info.VR is None:
255        return 1.0, 1.0
256
257    nvalues = model_info.parameters.nvalues
258    value = values[nvalues:nvalues + call_details.num_weights]
259    weight = values[nvalues + call_details.num_weights: nvalues + 2*call_details.num_weights]
260    npars = model_info.parameters.npars
261    pairs = [(value[offset:offset+length], weight[offset:offset+length])
262             for p, offset, length
263             in zip(model_info.parameters.call_parameters[2:2+npars],
264                    call_details.offset,
265                    call_details.length)
266             if p.type == 'volume']
267    value, weight = dispersion_mesh(model_info, pairs)
268
269    if model_info.ER is not None:
270        individual_radii = model_info.ER(*value)
271        radius_effective = np.sum(weight*individual_radii) / np.sum(weight)
272    else:
273        radius_effective = 1.0
274
275    if model_info.VR is not None:
276        whole, part = model_info.VR(*value)
277        volume_ratio = np.sum(weight*part)/np.sum(weight*whole)
278    else:
279        volume_ratio = 1.0
280
281    return radius_effective, volume_ratio
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