field.py 21.9 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
Theo Steininger's avatar
Theo Steininger committed
13
#
14
# Copyright(C) 2013-2019 Max-Planck-Society
Theo Steininger's avatar
Theo Steininger committed
15
#
16
# NIFTy is being developed at the Max-Planck-Institut fuer Astrophysik.
17

Martin Reinecke's avatar
Martin Reinecke committed
18
from functools import reduce
csongor's avatar
csongor committed
19
import numpy as np
20
21

from . import dobj, utilities
Martin Reinecke's avatar
Martin Reinecke committed
22
from .domain_tuple import DomainTuple
23

24

Martin Reinecke's avatar
Martin Reinecke committed
25
class Field(object):
26
    """The discrete representation of a continuous field over multiple spaces.
Theo Steininger's avatar
Theo Steininger committed
27

28
    Stores data arrays and carries all the needed meta-information (i.e. the
29
    domain) for operators to be able to operate on them.
Theo Steininger's avatar
Theo Steininger committed
30

31
32
    Parameters
    ----------
33
    domain : DomainTuple
Philipp Arras's avatar
Docs    
Philipp Arras committed
34
        The domain of the new Field.
35
36
37
    val : data_object
        This object's global shape must match the domain shape
        After construction, the object will no longer be writeable!
Martin Reinecke's avatar
Martin Reinecke committed
38

Martin Reinecke's avatar
Martin Reinecke committed
39
40
    Notes
    -----
Martin Reinecke's avatar
Martin Reinecke committed
41
    If possible, do not invoke the constructor directly, but use one of the
42
    many convenience functions for instantiation!
43
    """
44

45
46
    _scalar_dom = DomainTuple.scalar_domain()

47
48
49
    def __init__(self, domain, val):
        if not isinstance(domain, DomainTuple):
            raise TypeError("domain must be of type DomainTuple")
Martin Reinecke's avatar
Martin Reinecke committed
50
        if type(val) is not dobj.data_object:
Martin Reinecke's avatar
Martin Reinecke committed
51
            if np.isscalar(val):
Martin Reinecke's avatar
Martin Reinecke committed
52
                val = dobj.full(domain.shape, val)
Martin Reinecke's avatar
Martin Reinecke committed
53
54
            else:
                raise TypeError("val must be of type dobj.data_object")
55
        if domain.shape != val.shape:
Martin Reinecke's avatar
Martin Reinecke committed
56
            raise ValueError("shape mismatch between val and domain")
57
58
        self._domain = domain
        self._val = val
59
        dobj.lock(self._val)
Martin Reinecke's avatar
Martin Reinecke committed
60

Martin Reinecke's avatar
Martin Reinecke committed
61
62
63
64
    @staticmethod
    def scalar(val):
        return Field(Field._scalar_dom, val)

65
66
67
68
69
70
71
    # prevent implicit conversion to bool
    def __nonzero__(self):
        raise TypeError("Field does not support implicit conversion to bool")

    def __bool__(self):
        raise TypeError("Field does not support implicit conversion to bool")

72
    @staticmethod
73
    def full(domain, val):
Martin Reinecke's avatar
Martin Reinecke committed
74
75
76
77
78
        """Creates a Field with a given domain, filled with a constant value.

        Parameters
        ----------
        domain : Domain, tuple of Domain, or DomainTuple
Philipp Arras's avatar
Docs    
Philipp Arras committed
79
            Domain of the new Field.
Martin Reinecke's avatar
Martin Reinecke committed
80
        val : float/complex/int scalar
Philipp Arras's avatar
Docs    
Philipp Arras committed
81
            Fill value. Data type of the field is inferred from val.
Martin Reinecke's avatar
Martin Reinecke committed
82
83
84
85

        Returns
        -------
        Field
Philipp Arras's avatar
Docs    
Philipp Arras committed
86
            The newly created Field.
Martin Reinecke's avatar
Martin Reinecke committed
87
        """
88
89
        if not np.isscalar(val):
            raise TypeError("val must be a scalar")
90
91
92
        if not (np.isreal(val) or np.iscomplex(val)):
            raise TypeError("need arithmetic scalar")
        domain = DomainTuple.make(domain)
Martin Reinecke's avatar
Martin Reinecke committed
93
        return Field(domain, val)
94

95
    @staticmethod
96
    def from_global_data(domain, arr, sum_up=False):
Martin Reinecke's avatar
Martin Reinecke committed
97
98
99
100
101
        """Returns a Field constructed from `domain` and `arr`.

        Parameters
        ----------
        domain : DomainTuple, tuple of Domain, or Domain
Philipp Arras's avatar
Docs    
Philipp Arras committed
102
            The domain of the new Field.
Martin Reinecke's avatar
Martin Reinecke committed
103
104
105
        arr : numpy.ndarray
            The data content to be used for the new Field.
            Its shape must match the shape of `domain`.
106
107
108
109
110
        sum_up : bool, optional
            If True, the contents of `arr` are summed up over all MPI tasks
            (if any), and the sum is used as data content.
            If False, the contens of `arr` are used directly, and must be
            identical on all MPI tasks.
Martin Reinecke's avatar
Martin Reinecke committed
111
        """
112
113
        return Field(DomainTuple.make(domain),
                     dobj.from_global_data(arr, sum_up))
114

Martin Reinecke's avatar
Martin Reinecke committed
115
116
    @staticmethod
    def from_local_data(domain, arr):
117
        return Field(DomainTuple.make(domain),
Martin Reinecke's avatar
Martin Reinecke committed
118
                     dobj.from_local_data(domain.shape, arr))
Martin Reinecke's avatar
Martin Reinecke committed
119

120
    def to_global_data(self):
Martin Reinecke's avatar
Martin Reinecke committed
121
122
123
124
125
126
127
        """Returns an array containing the full data of the field.

        Returns
        -------
        numpy.ndarray : array containing all field entries.
            Its shape is identical to `self.shape`.
        """
128
129
        return dobj.to_global_data(self._val)

130
131
132
133
134
    def to_global_data_rw(self):
        """Returns a modifiable array containing the full data of the field.

        Returns
        -------
Philipp Arras's avatar
Docs    
Philipp Arras committed
135
136
137
        numpy.ndarray
            Array containing all field entries, which can be modified. Its
            shape is identical to `self.shape`.
138
139
140
        """
        return dobj.to_global_data_rw(self._val)

Martin Reinecke's avatar
Martin Reinecke committed
141
142
    @property
    def local_data(self):
Martin Reinecke's avatar
Martin Reinecke committed
143
144
145
146
147
        """numpy.ndarray : locally residing field data

        Returns a handle to the part of the array data residing on the local
        task (or to the entore array if MPI is not active).
        """
Martin Reinecke's avatar
Martin Reinecke committed
148
149
        return dobj.local_data(self._val)

Martin Reinecke's avatar
Martin Reinecke committed
150
    def cast_domain(self, new_domain):
Martin Reinecke's avatar
Martin Reinecke committed
151
152
153
154
155
156
157
158
159
160
161
        """Returns a field with the same data, but a different domain

        Parameters
        ----------
        new_domain : Domain, tuple of Domain, or DomainTuple
            The domain for the returned field. Must be shape-compatible to
            `self`.

        Returns
        -------
        Field
Philipp Arras's avatar
Philipp Arras committed
162
            Field defined on `new_domain`, but with the same data as `self`.
Martin Reinecke's avatar
Martin Reinecke committed
163
        """
164
        return Field(DomainTuple.make(new_domain), self._val)
165

Martin Reinecke's avatar
Martin Reinecke committed
166
167
    @staticmethod
    def from_random(random_type, domain, dtype=np.float64, **kwargs):
168
        """Draws a random field with the given parameters.
169
170
171

        Parameters
        ----------
Martin Reinecke's avatar
Martin Reinecke committed
172
173
        random_type : 'pm1', 'normal', or 'uniform'
            The random distribution to use.
Martin Reinecke's avatar
Martin Reinecke committed
174
        domain : DomainTuple
Philipp Arras's avatar
Docs    
Philipp Arras committed
175
            The domain of the output random Field.
176
        dtype : type
Philipp Arras's avatar
Docs    
Philipp Arras committed
177
            The datatype of the output random Field.
Theo Steininger's avatar
Theo Steininger committed
178

179
180
        Returns
        -------
Martin Reinecke's avatar
Martin Reinecke committed
181
        Field
Martin Reinecke's avatar
Martin Reinecke committed
182
            The newly created Field.
183
        """
Martin Reinecke's avatar
Martin Reinecke committed
184
        domain = DomainTuple.make(domain)
Martin Reinecke's avatar
Martin Reinecke committed
185
186
187
        return Field(domain=domain,
                     val=dobj.from_random(random_type, dtype=dtype,
                                          shape=domain.shape, **kwargs))
188

theos's avatar
theos committed
189
190
    @property
    def val(self):
Philipp Arras's avatar
Docs    
Philipp Arras committed
191
        """dobj.data_object : the data object storing the field's entries.
Martin Reinecke's avatar
Martin Reinecke committed
192

Martin Reinecke's avatar
Martin Reinecke committed
193
194
        Notes
        -----
Martin Reinecke's avatar
Martin Reinecke committed
195
196
        This property is intended for low-level, internal use only. Do not use
        from outside of NIFTy's core; there should be better alternatives.
197
        """
Martin Reinecke's avatar
Martin Reinecke committed
198
        return self._val
csongor's avatar
csongor committed
199

Martin Reinecke's avatar
Martin Reinecke committed
200
201
    @property
    def dtype(self):
Martin Reinecke's avatar
Martin Reinecke committed
202
        """type : the data type of the field's entries"""
Martin Reinecke's avatar
Martin Reinecke committed
203
204
        return self._val.dtype

Martin Reinecke's avatar
Martin Reinecke committed
205
206
    @property
    def domain(self):
Martin Reinecke's avatar
Martin Reinecke committed
207
        """DomainTuple : the field's domain"""
Martin Reinecke's avatar
Martin Reinecke committed
208
209
        return self._domain

210
211
    @property
    def shape(self):
Martin Reinecke's avatar
Martin Reinecke committed
212
        """tuple of int : the concatenated shapes of all sub-domains"""
Martin Reinecke's avatar
Martin Reinecke committed
213
        return self._domain.shape
csongor's avatar
csongor committed
214

215
    @property
Martin Reinecke's avatar
Martin Reinecke committed
216
    def size(self):
Martin Reinecke's avatar
Martin Reinecke committed
217
        """int : total number of pixels in the field"""
Martin Reinecke's avatar
Martin Reinecke committed
218
        return self._domain.size
csongor's avatar
csongor committed
219

Theo Steininger's avatar
Theo Steininger committed
220
221
    @property
    def real(self):
Martin Reinecke's avatar
Martin Reinecke committed
222
        """Field : The real part of the field"""
Martin Reinecke's avatar
Martin Reinecke committed
223
224
225
        if utilities.iscomplextype(self.dtype):
            return Field(self._domain, self._val.real)
        return self
Theo Steininger's avatar
Theo Steininger committed
226
227
228

    @property
    def imag(self):
Martin Reinecke's avatar
Martin Reinecke committed
229
        """Field : The imaginary part of the field"""
Martin Reinecke's avatar
Martin Reinecke committed
230
        if not utilities.iscomplextype(self.dtype):
231
            raise ValueError(".imag called on a non-complex Field")
Martin Reinecke's avatar
Martin Reinecke committed
232
        return Field(self._domain, self._val.imag)
Theo Steininger's avatar
Theo Steininger committed
233

234
    def scalar_weight(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
235
236
        """Returns the uniform volume element for a sub-domain of `self`.

237
238
        DEPRECATED! Use `self.domain.scalar_weight` instead.

Martin Reinecke's avatar
Martin Reinecke committed
239
240
241
        Parameters
        ----------
        spaces : int, tuple of int or None
Philipp Arras's avatar
Docs    
Philipp Arras committed
242
            Indices of the sub-domains of the field's domain to be considered.
Martin Reinecke's avatar
Martin Reinecke committed
243
244
245
246
247
            If `None`, the entire domain is used.

        Returns
        -------
        float or None
Philipp Arras's avatar
Docs    
Philipp Arras committed
248
            If the requested sub-domain has a uniform volume element, it is
Martin Reinecke's avatar
Martin Reinecke committed
249
250
            returned. Otherwise, `None` is returned.
        """
251
        return self._domain.scalar_weight(spaces)
252

Martin Reinecke's avatar
Martin Reinecke committed
253
    def total_volume(self, spaces=None):
254
        """Returns the total volume of the field's domain or of a subspace of it.
Martin Reinecke's avatar
Martin Reinecke committed
255

256
257
        DEPRECATED! Use `self.domain.total_volume` instead.

Martin Reinecke's avatar
Martin Reinecke committed
258
259
260
        Parameters
        ----------
        spaces : int, tuple of int or None
Philipp Arras's avatar
Docs    
Philipp Arras committed
261
            Indices of the sub-domains of the field's domain to be considered.
262
            If `None`, the total volume of the whole domain is returned.
Martin Reinecke's avatar
Martin Reinecke committed
263
264
265
266

        Returns
        -------
        float
267
            the total volume of the requested (sub-)domain.
Martin Reinecke's avatar
Martin Reinecke committed
268
        """
269
        return self._domain.total_volume(spaces)
Martin Reinecke's avatar
Martin Reinecke committed
270

271
    def weight(self, power=1, spaces=None):
272
        """Weights the pixels of `self` with their invidual pixel volumes.
273
274
275
276

        Parameters
        ----------
        power : number
277
            The pixel values get multiplied with their volume-factor**power.
Theo Steininger's avatar
Theo Steininger committed
278

Martin Reinecke's avatar
Martin Reinecke committed
279
280
281
        spaces : None, int or tuple of int
            Determines on which sub-domain the operation takes place.
            If None, the entire domain is used.
Theo Steininger's avatar
Theo Steininger committed
282

283
284
        Returns
        -------
Martin Reinecke's avatar
Martin Reinecke committed
285
        Field
Theo Steininger's avatar
Theo Steininger committed
286
            The weighted field.
287
        """
288
        aout = self.local_data.copy()
csongor's avatar
csongor committed
289

Martin Reinecke's avatar
Martin Reinecke committed
290
        spaces = utilities.parse_spaces(spaces, len(self._domain))
csongor's avatar
csongor committed
291

292
293
        fct = 1.
        for ind in spaces:
Martin Reinecke's avatar
Martin Reinecke committed
294
            wgt = self._domain[ind].dvol
295
296
297
            if np.isscalar(wgt):
                fct *= wgt
            else:
Martin Reinecke's avatar
Martin Reinecke committed
298
                new_shape = np.ones(len(self.shape), dtype=np.int)
Martin Reinecke's avatar
Martin Reinecke committed
299
300
                new_shape[self._domain.axes[ind][0]:
                          self._domain.axes[ind][-1]+1] = wgt.shape
301
                wgt = wgt.reshape(new_shape)
Martin Reinecke's avatar
Martin Reinecke committed
302
303
                if dobj.distaxis(self._val) >= 0 and ind == 0:
                    # we need to distribute the weights along axis 0
Martin Reinecke's avatar
fixes    
Martin Reinecke committed
304
                    wgt = dobj.local_data(dobj.from_global_data(wgt))
305
                aout *= wgt**power
306
        fct = fct**power
Martin Reinecke's avatar
Martin Reinecke committed
307
        if fct != 1.:
308
            aout *= fct
309

310
        return Field.from_local_data(self._domain, aout)
csongor's avatar
csongor committed
311

312
    def outer(self, x):
313
        """Computes the outer product of 'self' with x.
314
315
316
317
318
319

        Parameters
        ----------
        x : Field

        Returns
Philipp Arras's avatar
Docs    
Philipp Arras committed
320
321
322
        -------
        Field
            Defined on the product space of self.domain and x.domain.
323
324
325
        """
        if not isinstance(x, Field):
            raise TypeError("The multiplier must be an instance of " +
326
                            "the Field class")
327
328
329
        from .operators.outer_product_operator import OuterProduct
        return OuterProduct(self, x.domain)(x)

Martin Reinecke's avatar
Martin Reinecke committed
330
    def vdot(self, x=None, spaces=None):
331
        """Computes the dot product of 'self' with x.
Theo Steininger's avatar
Theo Steininger committed
332

333
334
335
        Parameters
        ----------
        x : Field
Philipp Arras's avatar
Philipp Arras committed
336
            x must be defined on the same domain as `self`.
Theo Steininger's avatar
Theo Steininger committed
337

Philipp Arras's avatar
Philipp Arras committed
338
        spaces : None, int or tuple of int
339
340
            The dot product is only carried out over the sub-domains in this
            tuple. If None, it is carried out over all sub-domains.
Philipp Arras's avatar
Philipp Arras committed
341
            Default: None.
Theo Steininger's avatar
Theo Steininger committed
342

343
344
        Returns
        -------
Philipp Arras's avatar
Philipp Arras committed
345
        float, complex, either scalar (for full dot products) or Field (for partial dot products).
346
        """
347
        if not isinstance(x, Field):
348
            raise TypeError("The dot-partner must be an instance of " +
349
                            "the Field class")
theos's avatar
theos committed
350

Martin Reinecke's avatar
Martin Reinecke committed
351
        if x._domain != self._domain:
352
            raise ValueError("Domain mismatch")
theos's avatar
theos committed
353

Martin Reinecke's avatar
Martin Reinecke committed
354
        ndom = len(self._domain)
355
356
357
        spaces = utilities.parse_spaces(spaces, ndom)

        if len(spaces) == ndom:
Martin Reinecke's avatar
Martin Reinecke committed
358
            return dobj.vdot(self._val, x._val)
359
360
        # If we arrive here, we have to do a partial dot product.
        # For the moment, do this the explicit, non-optimized way
Martin Reinecke's avatar
Martin Reinecke committed
361
        return (self.conjugate()*x).sum(spaces=spaces)
theos's avatar
theos committed
362

Martin Reinecke's avatar
Martin Reinecke committed
363
    def norm(self, ord=2):
364
        """Computes the L2-norm of the field values.
csongor's avatar
csongor committed
365

Martin Reinecke's avatar
Martin Reinecke committed
366
367
        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
368
369
        ord : int
            Accepted values: 1, 2, ..., np.inf. Default: 2.
370
371
372
373

        Returns
        -------
        float
Martin Reinecke's avatar
Martin Reinecke committed
374
            The L2-norm of the field values.
375
        """
Martin Reinecke's avatar
Martin Reinecke committed
376
        return dobj.norm(self._val, ord)
377

Martin Reinecke's avatar
tweaks    
Martin Reinecke committed
378
    def conjugate(self):
379
        """Returns the complex conjugate of the field.
Theo Steininger's avatar
Theo Steininger committed
380

381
382
        Returns
        -------
Martin Reinecke's avatar
Martin Reinecke committed
383
384
        Field
            The complex conjugated field.
csongor's avatar
csongor committed
385
        """
Martin Reinecke's avatar
Martin Reinecke committed
386
        if utilities.iscomplextype(self._val.dtype):
Martin Reinecke's avatar
Martin Reinecke committed
387
388
            return Field(self._domain, self._val.conjugate())
        return self
csongor's avatar
csongor committed
389

theos's avatar
theos committed
390
    # ---General unary/contraction methods---
391

theos's avatar
theos committed
392
    def __pos__(self):
393
        return self
394

theos's avatar
theos committed
395
    def __neg__(self):
Martin Reinecke's avatar
Martin Reinecke committed
396
        return Field(self._domain, -self._val)
csongor's avatar
csongor committed
397

theos's avatar
theos committed
398
    def __abs__(self):
Martin Reinecke's avatar
Martin Reinecke committed
399
        return Field(self._domain, abs(self._val))
csongor's avatar
csongor committed
400

401
    def _contraction_helper(self, op, spaces):
theos's avatar
theos committed
402
        if spaces is None:
Martin Reinecke's avatar
Martin Reinecke committed
403
            return getattr(self._val, op)()
404

Martin Reinecke's avatar
Martin Reinecke committed
405
        spaces = utilities.parse_spaces(spaces, len(self._domain))
csongor's avatar
csongor committed
406

Martin Reinecke's avatar
Martin Reinecke committed
407
        axes_list = tuple(self._domain.axes[sp_index] for sp_index in spaces)
408

Martin Reinecke's avatar
Martin Reinecke committed
409
        if len(axes_list) > 0:
theos's avatar
theos committed
410
            axes_list = reduce(lambda x, y: x+y, axes_list)
csongor's avatar
csongor committed
411

Martin Reinecke's avatar
stage1    
Martin Reinecke committed
412
        # perform the contraction on the data
Martin Reinecke's avatar
Martin Reinecke committed
413
        data = getattr(self._val, op)(axis=axes_list)
csongor's avatar
csongor committed
414

theos's avatar
theos committed
415
416
417
        # check if the result is scalar or if a result_field must be constr.
        if np.isscalar(data):
            return data
csongor's avatar
csongor committed
418
        else:
Martin Reinecke's avatar
Martin Reinecke committed
419
            return_domain = tuple(dom
Martin Reinecke's avatar
Martin Reinecke committed
420
                                  for i, dom in enumerate(self._domain)
theos's avatar
theos committed
421
                                  if i not in spaces)
422

423
            return Field(DomainTuple.make(return_domain), data)
csongor's avatar
csongor committed
424

425
    def sum(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
426
427
428
429
        """Sums up over the sub-domains given by `spaces`.

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
430
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
431
            The summation is only carried out over the sub-domains in this
Martin Reinecke's avatar
cleanup    
Martin Reinecke committed
432
            tuple. If None, it is carried out over all sub-domains.
Martin Reinecke's avatar
Martin Reinecke committed
433
434
435
436
437
438
439

        Returns
        -------
        Field or scalar
            The result of the summation. If it is carried out over the entire
            domain, this is a scalar, otherwise a Field.
        """
440
        return self._contraction_helper('sum', spaces)
csongor's avatar
csongor committed
441

442
    def integrate(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
443
444
445
446
447
448
449
        """Integrates over the sub-domains given by `spaces`.

        Integration is performed by summing over `self` multiplied by its
        volume factors.

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
450
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
451
452
453
454
455
456
457
458
459
            The summation is only carried out over the sub-domains in this
            tuple. If None, it is carried out over all sub-domains.

        Returns
        -------
        Field or scalar
            The result of the integration. If it is carried out over the
            entire domain, this is a scalar, otherwise a Field.
        """
460
        swgt = self._domain.scalar_weight(spaces)
Martin Reinecke's avatar
Martin Reinecke committed
461
462
        if swgt is not None:
            res = self.sum(spaces)
Martin Reinecke's avatar
fixes    
Martin Reinecke committed
463
            res = res*swgt
Martin Reinecke's avatar
Martin Reinecke committed
464
            return res
465
466
467
        tmp = self.weight(1, spaces=spaces)
        return tmp.sum(spaces)

468
    def prod(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
469
470
471
472
        """Computes the product over the sub-domains given by `spaces`.

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
473
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
474
475
            The operation is only carried out over the sub-domains in this
            tuple. If None, it is carried out over all sub-domains.
Philipp Arras's avatar
Philipp Arras committed
476
            Default: None.
Martin Reinecke's avatar
Martin Reinecke committed
477
478
479
480
481
482
483

        Returns
        -------
        Field or scalar
            The result of the product. If it is carried out over the entire
            domain, this is a scalar, otherwise a Field.
        """
484
        return self._contraction_helper('prod', spaces)
csongor's avatar
csongor committed
485

486
487
    def all(self, spaces=None):
        return self._contraction_helper('all', spaces)
csongor's avatar
csongor committed
488

489
490
    def any(self, spaces=None):
        return self._contraction_helper('any', spaces)
csongor's avatar
csongor committed
491

492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
#     def min(self, spaces=None):
#         """Determines the minimum over the sub-domains given by `spaces`.
#
#         Parameters
#         ----------
#         spaces : None, int or tuple of int (default: None)
#             The operation is only carried out over the sub-domains in this
#             tuple. If None, it is carried out over all sub-domains.
#
#         Returns
#         -------
#         Field or scalar
#             The result of the operation. If it is carried out over the entire
#             domain, this is a scalar, otherwise a Field.
#         """
#         return self._contraction_helper('min', spaces)
#
#     def max(self, spaces=None):
#         """Determines the maximum over the sub-domains given by `spaces`.
#
#         Parameters
#         ----------
#         spaces : None, int or tuple of int (default: None)
#             The operation is only carried out over the sub-domains in this
#             tuple. If None, it is carried out over all sub-domains.
#
#         Returns
#         -------
#         Field or scalar
#             The result of the operation. If it is carried out over the entire
#             domain, this is a scalar, otherwise a Field.
#         """
#         return self._contraction_helper('max', spaces)
csongor's avatar
csongor committed
525

526
    def mean(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
527
528
529
        """Determines the mean over the sub-domains given by `spaces`.

        ``x.mean(spaces)`` is equivalent to
530
        ``x.integrate(spaces)/x.domain.total_volume(spaces)``.
Martin Reinecke's avatar
Martin Reinecke committed
531
532
533

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
534
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
535
            The operation is only carried out over the sub-domains in this
Martin Reinecke's avatar
cleanup    
Martin Reinecke committed
536
            tuple. If None, it is carried out over all sub-domains.
Martin Reinecke's avatar
Martin Reinecke committed
537
538
539
540
541
542
543

        Returns
        -------
        Field or scalar
            The result of the operation. If it is carried out over the entire
            domain, this is a scalar, otherwise a Field.
        """
544
        if self._domain.scalar_weight(spaces) is not None:
545
            return self._contraction_helper('mean', spaces)
Martin Reinecke's avatar
Martin Reinecke committed
546
        # MR FIXME: not very efficient
547
548
        # MR FIXME: do we need "spaces" here?
        tmp = self.weight(1, spaces)
549
        return tmp.sum(spaces)*(1./tmp._domain.total_volume(spaces))
csongor's avatar
csongor committed
550

551
    def var(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
552
553
554
555
        """Determines the variance over the sub-domains given by `spaces`.

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
556
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
557
558
            The operation is only carried out over the sub-domains in this
            tuple. If None, it is carried out over all sub-domains.
Philipp Arras's avatar
Philipp Arras committed
559
            Default: None.
Martin Reinecke's avatar
Martin Reinecke committed
560
561
562
563
564
565
566

        Returns
        -------
        Field or scalar
            The result of the operation. If it is carried out over the entire
            domain, this is a scalar, otherwise a Field.
        """
567
        if self._domain.scalar_weight(spaces) is not None:
568
            return self._contraction_helper('var', spaces)
Martin Reinecke's avatar
Martin Reinecke committed
569
570
        # MR FIXME: not very efficient or accurate
        m1 = self.mean(spaces)
Martin Reinecke's avatar
Martin Reinecke committed
571
        if utilities.iscomplextype(self.dtype):
572
            sq = abs(self-m1)**2
Martin Reinecke's avatar
Martin Reinecke committed
573
        else:
574
575
            sq = (self-m1)**2
        return sq.mean(spaces)
csongor's avatar
csongor committed
576

577
    def std(self, spaces=None):
Martin Reinecke's avatar
Martin Reinecke committed
578
579
580
581
582
583
584
        """Determines the standard deviation over the sub-domains given by
        `spaces`.

        ``x.std(spaces)`` is equivalent to ``sqrt(x.var(spaces))``.

        Parameters
        ----------
Philipp Arras's avatar
Philipp Arras committed
585
        spaces : None, int or tuple of int
Martin Reinecke's avatar
Martin Reinecke committed
586
587
            The operation is only carried out over the sub-domains in this
            tuple. If None, it is carried out over all sub-domains.
Philipp Arras's avatar
Philipp Arras committed
588
            Default: None.
Martin Reinecke's avatar
Martin Reinecke committed
589
590
591
592
593
594
595

        Returns
        -------
        Field or scalar
            The result of the operation. If it is carried out over the entire
            domain, this is a scalar, otherwise a Field.
        """
596
        from .sugar import sqrt
597
        if self._domain.scalar_weight(spaces) is not None:
598
599
            return self._contraction_helper('std', spaces)
        return sqrt(self.var(spaces))
csongor's avatar
csongor committed
600

theos's avatar
theos committed
601
    def __repr__(self):
Philipp Arras's avatar
Philipp Arras committed
602
        return "<nifty5.Field>"
theos's avatar
theos committed
603
604

    def __str__(self):
Philipp Arras's avatar
Philipp Arras committed
605
        return "nifty5.Field instance\n- domain      = " + \
606
               self._domain.__str__() + \
Martin Reinecke's avatar
Martin Reinecke committed
607
               "\n- val         = " + repr(self._val)
Martin Reinecke's avatar
cleanup    
Martin Reinecke committed
608

Martin Reinecke's avatar
more    
Martin Reinecke committed
609
    def extract(self, dom):
Martin Reinecke's avatar
Martin Reinecke committed
610
        if dom != self._domain:
Martin Reinecke's avatar
more    
Martin Reinecke committed
611
612
613
            raise ValueError("domain mismatch")
        return self

614
615
616
    def extract_part(self, dom):
        if dom != self._domain:
            raise ValueError("domain mismatch")
Martin Reinecke's avatar
more    
Martin Reinecke committed
617
618
619
        return self

    def unite(self, other):
Martin Reinecke's avatar
Martin Reinecke committed
620
621
622
623
        return self+other

    def flexible_addsub(self, other, neg):
        return self-other if neg else self+other
624

625
    def sigmoid(self):
Martin Reinecke's avatar
Martin Reinecke committed
626
627
        return 0.5*(1.+self.tanh())

Martin Reinecke's avatar
Martin Reinecke committed
628
    def clip(self, min=None, max=None):
Martin Reinecke's avatar
tweaks    
Martin Reinecke committed
629
630
        min = min.local_data if isinstance(min, Field) else min
        max = max.local_data if isinstance(max, Field) else max
Martin Reinecke's avatar
Martin Reinecke committed
631
        return Field(self._domain, dobj.clip(self._val, min, max))
632
633
634
635

    def one_over(self):
        return 1/self

Martin Reinecke's avatar
Martin Reinecke committed
636
637
638
639
    def _binary_op(self, other, op):
        # if other is a field, make sure that the domains match
        f = getattr(self._val, op)
        if isinstance(other, Field):
Martin Reinecke's avatar
Martin Reinecke committed
640
            if other._domain != self._domain:
Martin Reinecke's avatar
Martin Reinecke committed
641
642
643
644
645
                raise ValueError("domains are incompatible.")
            return Field(self._domain, f(other._val))
        if np.isscalar(other):
            return Field(self._domain, f(other))
        return NotImplemented
Martin Reinecke's avatar
Martin Reinecke committed
646

Martin Reinecke's avatar
Martin Reinecke committed
647

Martin Reinecke's avatar
Martin Reinecke committed
648
649
650
for op in ["__add__", "__radd__",
           "__sub__", "__rsub__",
           "__mul__", "__rmul__",
651
652
653
           "__truediv__", "__rtruediv__",
           "__floordiv__", "__rfloordiv__",
           "__pow__", "__rpow__",
654
655
656
           "__lt__", "__le__", "__gt__", "__ge__", "__eq__", "__ne__"]:
    def func(op):
        def func2(self, other):
Martin Reinecke's avatar
Martin Reinecke committed
657
            return self._binary_op(other, op)
658
659
        return func2
    setattr(Field, op, func(op))
660
661
662
663
664
665
666
667
668

for op in ["__iadd__", "__isub__", "__imul__", "__idiv__",
           "__itruediv__", "__ifloordiv__", "__ipow__"]:
    def func(op):
        def func2(self, other):
            raise TypeError(
                "In-place operations are deliberately not supported")
        return func2
    setattr(Field, op, func(op))
Martin Reinecke's avatar
Martin Reinecke committed
669

670
671
672
for f in ["sqrt", "exp", "log", "tanh",
          "sin", "cos", "tan", "cosh", "sinh",
          "absolute", "sinc", "sign"]:
Martin Reinecke's avatar
Martin Reinecke committed
673
674
    def func(f):
        def func2(self):
Martin Reinecke's avatar
Martin Reinecke committed
675
            return Field(self._domain, getattr(dobj, f)(self.val))
Martin Reinecke's avatar
Martin Reinecke committed
676
677
        return func2
    setattr(Field, f, func(f))