Coverage for gpkit/constraints/set.py: 86%
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1"Implements ConstraintSet"
2import sys
3from collections import defaultdict, OrderedDict
4from itertools import chain
5import numpy as np
6from ..keydict import KeySet, KeyDict
7from ..small_scripts import try_str_without
8from ..repr_conventions import ReprMixin
9from .single_equation import SingleEquationConstraint
12def add_meq_bounds(bounded, meq_bounded): #TODO: collapse with GP version?
13 "Iterates through meq_bounds until convergence"
14 still_alive = True
15 while still_alive:
16 still_alive = False # if no changes are made, the loop exits
17 for bound in list(meq_bounded):
18 if bound in bounded: # bound already exists
19 del meq_bounded[bound]
20 continue
21 for condition in meq_bounded[bound]:
22 if condition.issubset(bounded): # bound's condition is met
23 del meq_bounded[bound]
24 bounded.add(bound)
25 still_alive = True
26 break
28def _sort_by_name_and_idx(var):
29 "return tuple for Variable sorting"
30 return (var.key.str_without(["units", "idx"]), var.key.idx or ())
32def _sort_constraints(item):
33 "return tuple for Constraint sorting"
34 label, constraint = item
35 return (not isinstance(constraint, SingleEquationConstraint),
36 bool(getattr(constraint, "lineage", None)), label)
38def sort_constraints_dict(iterable):
39 "Sort a dictionary of {k: constraint} and return its keys and values"
40 if sys.version_info >= (3, 7) or isinstance(iterable, OrderedDict):
41 return iterable.keys(), iterable.values()
42 items = sorted(list(iterable.items()), key=_sort_constraints)
43 return (item[0] for item in items), (item[1] for item in items)
45def flatiter(iterable, yield_if_hasattr=None):
46 "Yields contained constraints, optionally including constraintsets."
47 if isinstance(iterable, dict):
48 _, iterable = sort_constraints_dict(iterable)
49 for constraint in iterable:
50 if (not hasattr(constraint, "__iter__")
51 or (yield_if_hasattr
52 and hasattr(constraint, yield_if_hasattr))):
53 yield constraint
54 else:
55 try: # numpy array
56 yield from constraint.flat
57 except TypeError: # ConstrainSet
58 yield from constraint.flat(yield_if_hasattr)
59 except AttributeError: # probably a list or dict
60 yield from flatiter(constraint, yield_if_hasattr)
63class ConstraintSet(list, ReprMixin): # pylint: disable=too-many-instance-attributes
64 "Recursive container for ConstraintSets and Inequalities"
65 unique_varkeys, idxlookup = frozenset(), {}
66 _name_collision_varkeys = None
67 _varkeys = None
68 _lineageset = False
70 def __init__(self, constraints, substitutions=None, *, bonusvks=None): # pylint: disable=too-many-branches,too-many-statements
71 if isinstance(constraints, dict):
72 keys, constraints = sort_constraints_dict(constraints)
73 self.idxlookup = {k: i for i, k in enumerate(keys)}
74 elif isinstance(constraints, ConstraintSet):
75 constraints = [constraints] # put it one level down
76 list.__init__(self, constraints)
77 self.vks = set(self.unique_varkeys)
78 self.substitutions = KeyDict({k: k.value for k in self.unique_varkeys
79 if "value" in k.descr})
80 self.substitutions.vks = self.vks
81 self.bounded, self.meq_bounded = set(), defaultdict(set)
82 for i, constraint in enumerate(self):
83 if hasattr(constraint, "vks"):
84 self._update(constraint)
85 elif not (hasattr(constraint, "as_hmapslt1")
86 or hasattr(constraint, "as_gpconstr")):
87 try:
88 for subconstraint in flatiter(constraint, "vks"):
89 self._update(subconstraint)
90 except Exception as e:
91 raise badelement(self, i, constraint) from e
92 elif isinstance(constraint, ConstraintSet):
93 raise badelement(self, i, constraint,
94 " It had not yet been initialized!")
95 if bonusvks:
96 self.vks.update(bonusvks)
97 if substitutions:
98 self.substitutions.update(substitutions)
99 for key in self.vks:
100 if key not in self.substitutions:
101 if key.veckey is None or key.veckey not in self.substitutions:
102 continue
103 if np.isnan(self.substitutions[key.veckey][key.idx]):
104 continue
105 self.bounded.add((key, "upper"))
106 self.bounded.add((key, "lower"))
107 if key.value is not None and not key.constant:
108 del key.descr["value"]
109 if key.veckey and key.veckey.value is not None:
110 del key.veckey.descr["value"]
111 add_meq_bounds(self.bounded, self.meq_bounded)
113 def _update(self, constraint):
114 "Update parameters with a given constraint"
115 self.vks.update(constraint.vks)
116 if hasattr(constraint, "substitutions"):
117 self.substitutions.update(constraint.substitutions)
118 else:
119 self.substitutions.update({k: k.value \
120 for k in constraint.vks if "value" in k.descr})
121 self.bounded.update(constraint.bounded)
122 for bound, solutionset in constraint.meq_bounded.items():
123 self.meq_bounded[bound].update(solutionset)
125 def __getitem__(self, key):
126 if key in self.idxlookup:
127 key = self.idxlookup[key]
128 if isinstance(key, int):
129 return list.__getitem__(self, key)
130 return self._choosevar(key, self.variables_byname(key))
132 def _choosevar(self, key, variables):
133 if not variables:
134 raise KeyError(key)
135 firstvar, *othervars = variables
136 veckey = firstvar.key.veckey
137 if veckey is None or any(v.key.veckey != veckey for v in othervars):
138 if not othervars:
139 return firstvar
140 raise ValueError("multiple variables are called '%s'; show them"
141 " with `.variables_byname('%s')`" % (key, key))
142 from ..nomials import NomialArray # all one vector!
143 arr = NomialArray(np.full(veckey.shape, np.nan, dtype="object"))
144 for v in variables:
145 arr[v.key.idx] = v
146 arr.key = veckey
147 return arr
149 def variables_byname(self, key):
150 "Get all variables with a given name"
151 from ..nomials import Variable
152 return sorted([Variable(k) for k in self.varkeys[key]],
153 key=_sort_by_name_and_idx)
155 @property
156 def varkeys(self):
157 "The NomialData's varkeys, created when necessary for a substitution."
158 if self._varkeys is None:
159 self._varkeys = KeySet(self.vks)
160 return self._varkeys
162 def constrained_varkeys(self):
163 "Return all varkeys in non-ConstraintSet constraints"
164 return self.vks - self.unique_varkeys
166 flat = flatiter
168 def as_hmapslt1(self, subs):
169 "Yields hmaps<=1 from self.flat()"
170 yield from chain(*(c.as_hmapslt1(subs)
171 for c in flatiter(self,
172 yield_if_hasattr="as_hmapslt1")))
174 def process_result(self, result):
175 """Does arbitrary computation / manipulation of a program's result
177 There's no guarantee what order different constraints will process
178 results in, so any changes made to the program's result should be
179 careful not to step on other constraint's toes.
181 Potential Uses
182 --------------
183 - check that an inequality was tight
184 - add values computed from solved variables
186 """
187 for constraint in self.flat(yield_if_hasattr="process_result"):
188 if hasattr(constraint, "process_result"):
189 constraint.process_result(result)
190 evalfn_vars = {v.veckey or v for v in self.unique_varkeys
191 if v.evalfn and v not in result["variables"]}
192 for v in evalfn_vars:
193 val = v.evalfn(result["variables"])
194 result["variables"][v] = result["freevariables"][v] = val
196 def __repr__(self):
197 "Returns namespaced string."
198 if not self:
199 return "<gpkit.%s object>" % self.__class__.__name__
200 return ("<gpkit.%s object containing %i top-level constraint(s)"
201 " and %i variable(s)>" % (self.__class__.__name__,
202 len(self), len(self.varkeys)))
204 def set_necessarylineage(self, clear=False): # pylint: disable=too-many-branches
205 "Returns the set of contained varkeys whose names are not unique"
206 if self._name_collision_varkeys is None:
207 self._name_collision_varkeys = {}
208 name_collisions = defaultdict(set)
209 for key in self.varkeys:
210 if hasattr(key, "key"):
211 if key.veckey and all(k.veckey == key.veckey
212 for k in self.varkeys[key.name]):
213 self._name_collision_varkeys[key] = 0
214 self._name_collision_varkeys[key.veckey] = 0
215 elif len(self.varkeys[key.name]) == 1:
216 self._name_collision_varkeys[key] = 0
217 else:
218 shortname = key.str_without(["lineage", "vec"])
219 if len(self.varkeys[shortname]) > 1:
220 name_collisions[shortname].add(key)
221 for varkeys in name_collisions.values():
222 min_namespaced = defaultdict(set)
223 for vk in varkeys:
224 *_, mineage = vk.lineagestr().split(".")
225 min_namespaced[(mineage, 1)].add(vk)
226 while any(len(vks) > 1 for vks in min_namespaced.values()):
227 for key, vks in list(min_namespaced.items()):
228 if len(vks) <= 1:
229 continue
230 del min_namespaced[key]
231 mineage, idx = key
232 idx += 1
233 for vk in vks:
234 lineages = vk.lineagestr().split(".")
235 submineage = lineages[-idx] + "." + mineage
236 min_namespaced[(submineage, idx)].add(vk)
237 for (_, idx), vks in min_namespaced.items():
238 vk, = vks
239 self._name_collision_varkeys[vk] = idx
240 if clear:
241 self._lineageset = False
242 for vk in self._name_collision_varkeys:
243 del vk.descr["necessarylineage"]
244 else:
245 self._lineageset = True
246 for vk, idx in self._name_collision_varkeys.items():
247 vk.descr["necessarylineage"] = idx
249 def lines_without(self, excluded):
250 "Lines representation of a ConstraintSet."
251 excluded = frozenset(excluded)
252 root, rootlines = "root" not in excluded, []
253 if root:
254 excluded = {"root"}.union(excluded)
255 self.set_necessarylineage()
256 if hasattr(self, "_rootlines"):
257 rootlines = self._rootlines(excluded) # pylint: disable=no-member
258 lines = recursively_line(self, excluded)
259 indent = " " if root or getattr(self, "lineage", None) else ""
260 if root:
261 self.set_necessarylineage(clear=True)
262 return rootlines + [(indent+line).rstrip() for line in lines]
264 def str_without(self, excluded=("units",)):
265 "String representation of a ConstraintSet."
266 return "\n".join(self.lines_without(excluded))
268 def latex(self, excluded=("units",)):
269 "LaTeX representation of a ConstraintSet."
270 lines = []
271 root = "root" not in excluded
272 if root:
273 excluded += ("root",)
274 lines.append("\\begin{array}{ll} \\text{}")
275 if hasattr(self, "_rootlatex"):
276 lines.append(self._rootlatex(excluded)) # pylint: disable=no-member
277 for constraint in self:
278 cstr = try_str_without(constraint, excluded, latex=True)
279 if cstr[:6] != " & ": # require indentation
280 cstr = " & " + cstr + " \\\\"
281 lines.append(cstr)
282 if root:
283 lines.append("\\end{array}")
284 return "\n".join(lines)
286 def as_view(self):
287 "Return a ConstraintSetView of this ConstraintSet."
288 return ConstraintSetView(self)
290def recursively_line(iterable, excluded):
291 "Generates lines in a recursive tree-like fashion, the better to indent."
292 named_constraints = {}
293 if isinstance(iterable, dict):
294 keys, iterable = sort_constraints_dict(iterable)
295 named_constraints = dict(enumerate(keys))
296 elif hasattr(iterable, "idxlookup"):
297 named_constraints = {i: k for k, i in iterable.idxlookup.items()}
298 lines = []
299 for i, constraint in enumerate(iterable):
300 if hasattr(constraint, "lines_without"):
301 clines = constraint.lines_without(excluded)
302 elif not hasattr(constraint, "__iter__"):
303 clines = try_str_without(constraint, excluded).split("\n")
304 elif iterable is constraint:
305 clines = ["(constraint contained itself)"]
306 else:
307 clines = recursively_line(constraint, excluded)
308 if (getattr(constraint, "lineage", None)
309 and isinstance(constraint, ConstraintSet)):
310 name, num = constraint.lineage[-1]
311 if not any(clines):
312 clines = [" " + "(no constraints)"] # named model indent
313 if lines:
314 lines.append("")
315 lines.append(name if not num else name + str(num))
316 elif "constraint names" not in excluded and i in named_constraints:
317 lines.append("\"%s\":" % named_constraints[i])
318 clines = [" " + line for line in clines] # named constraint indent
319 lines.extend(clines)
320 return lines
323class ConstraintSetView:
324 "Class to access particular views on a set's variables"
326 def __init__(self, constraintset, index=()):
327 self.constraintset = constraintset
328 try:
329 self.index = tuple(index)
330 except TypeError: # probably not iterable
331 self.index = (index,)
333 def __getitem__(self, index):
334 "Appends the index to its own and returns a new view."
335 if not isinstance(index, tuple):
336 index = (index,)
337 # indexes are preprended to match Vectorize convention
338 return ConstraintSetView(self.constraintset, index + self.index)
340 def __getattr__(self, attr):
341 """Returns attribute from the base ConstraintSets
343 If it's a another ConstraintSet, return the matching View;
344 if it's an array, return it at the specified index;
345 otherwise, raise an error.
346 """
347 if not hasattr(self.constraintset, attr):
348 raise AttributeError("the underlying object lacks `.%s`." % attr)
350 value = getattr(self.constraintset, attr)
351 if isinstance(value, ConstraintSet):
352 return ConstraintSetView(value, self.index)
353 if not hasattr(value, "shape"):
354 raise ValueError("attribute %s with value %s did not have"
355 " a shape, so ConstraintSetView cannot"
356 " return an indexed view." % (attr, value))
357 index = self.index
358 newdims = len(value.shape) - len(self.index)
359 if newdims > 0: # indexes are put last to match Vectorize
360 index = (slice(None),)*newdims + index
361 return value[index]
365def badelement(cns, i, constraint, cause=""):
366 "Identify the bad element and raise a ValueError"
367 cause = cause if not isinstance(constraint, bool) else (
368 " Did the constraint list contain an accidental equality?")
369 if len(cns) == 1:
370 loc = "the only constraint"
371 elif i == 0:
372 loc = "at the start, before %s" % cns[i+1]
373 elif i == len(cns) - 1:
374 loc = "at the end, after %s" % cns[i-1]
375 else:
376 loc = "between %s and %s" % (cns[i-1], cns[i+1])
377 return ValueError("Invalid ConstraintSet element '%s' %s was %s.%s"
378 % (repr(constraint), type(constraint), loc, cause))