import sys import re from collections import defaultdict import inspect import numpy as np import scipy.spatial from baker import run_baker from baker.tools import exact_func, smberror, smblog from simplex import face, contains from smcqdelaunay import * class grid(object): facet_re = re.compile(r''' -\s+(?Pf\d+).*? vertices:\s(?P.*?)\n.*? neighboring\s facets:\s+(?P[\sf\d]*) ''', re.S|re.X) point_re = re.compile(r''' -\s+(?Pp\d+).*? neighbors:\s+(?P[\sf\d]*) ''', re.S|re.X) vert_re = re.compile(r''' (p\d+) ''', re.S|re.X) def __init__(self, points, q): """ this thing eats two pre-constructed arrays of stuff: points = array of arrays (i will convert to numpy.array) [[x0,y0], [x1,y1], ...] q = array (1D) of important values """ self.points = np.array(points) self.q = np.array(q) self.tree = scipy.spatial.KDTree(self.points) self.faces = {} self.facets_for_point = defaultdict(list) def create_mesh(self, indicies): """ this function takes a list of indicies, and then creates and returns a grid object (collection of points and q). note: the input is indicies, the grid contains points """ p = [self.points[i] for i in indicies] q = [self.q[i] for i in indicies] return grid(p, q) def get_containing_simplex(self, X): if not self.faces: self.construct_connectivity() # get closest point (dist, indicies) = self.tree.query(X, 2) closest_point = indicies[0] smblog.debug('X: %s' % X) smblog.debug('point index: %d' % closest_point) smblog.debug('actual point %s' % self.points[closest_point]) smblog.debug('distance = %0.4f' % dist[0]) simplex = None checked_facets = [] facets_to_check = self.facets_for_point[closest_point] attempts = 0 while not simplex and facets_to_check: attempts += 1 # if attempts > 20: # raise smberror("probably recursing to many times") cur_facet = facets_to_check.pop(0) checked_facets.append(cur_facet) if cur_facet.contains(X, self): simplex = cur_facet continue new_facest = [] for neighbor in cur_facet.neighbors: if (neighbor not in checked_facets) and (neighbor not in facets_to_check): facets_to_check.append(neighbor) if not simplex: raise AssertionError('no containing simplex found') R = self.create_mesh(simplex.verts) smblog.debug('total attempts before finding simplex: %d' % attempts) return R def get_simplex_and_nearest_points(self, X, extra_points = 3, simplex_size = 3): """ this returns two grid objects: R and S. R is a grid object that is supposedly a containing simplex around point X (it tends not to be) S is S_j from baker's paper : some points from all point that are not the simplex """ smblog.debug(inspect.stack()[1][3]) smblog.debug("extra points: %d" % extra_points) smblog.debug("simplex size: %d" % simplex_size) r_mesh = self.get_containing_simplex(X) # smblog.debug("R:\n%s" % r_mesh) # and some UNIQUE extra points (dist, indicies) = self.tree.query(X, simplex_size + extra_points) unique_indicies = [] for index in indicies: if self.points[index] not in r_mesh.points: unique_indicies.append(index) smblog.debug("indicies: %s" % ",".join([str(i) for i in indicies])) smblog.debug("indicies: %s" % ",".join([str(i) for i in unique_indicies])) s_mesh = self.create_mesh(unique_indicies)# indicies[simplex_size:]) # TODO: eventually remove this test: for point in s_mesh.points: if point in r_mesh.points: smblog.error("ERROR") smblog.error("\n%s\nin\n%s" % (point, r_mesh)) raise smberror("repeating point S and R") return (r_mesh, s_mesh) def get_points_conn(self, X): """ this returns two grid objects: R and S. this function differes from the get_simplex_and_nearest_points function in that it builds up the extra points based on connectivity information, not just nearest-neighbor. in theory, this will work much better for situations like points near a short edge in a boundary layer cell where the nearest points would all be colinear also, it guarantees that we find a containing simplex R is a grid object that is the (a) containing simplex around point X S is a connectivity-based nearest-neighbor lookup, limited to 3 extra points """ if not self.faces: self.construct_connectivity() # get closest point (dist, indicies) = self.tree.query(X, 2) simplex = None for facet in self.facets_for_point[indicies[0]]: if facet.contains(X, self): simplex = facet break if not simplex: raise AssertionError('no containing simplex found') # self.create_mesh(simplex.verts) R = self.get_containing_simplex(X) s = [] for c,i in enumerate(simplex.neighbors): s.extend([guy for guy in i.verts if not guy in simplex.verts]) S = self.create_mesh(s) return R, S def run_baker(self, X, extra_points = 3, order = 2): answer = None try: (R, S) = self.get_simplex_and_nearest_points(X) if not contains(X, R.points): raise smberror("run_baker with get_simplex_and_nearest_points returned non-containing simplex") answer = run_baker(X, R, S, order) except smberror, e: smblog.error("caught error: %s, trying with connectivity-based mesh" % e) (R, S) = self.get_points_conn(X) answer = run_baker(X, R, S, order) return answer def construct_connectivity(self): """ a call to this method prepares the internal connectivity structure. this is part of the __init__ for a rect_grid, but can be called from any grid object """ smblog.debug('start') qdelaunay_string = get_qdelaunay_dump_str(self) facet_to_facets = [] for matcher in grid.facet_re.finditer(qdelaunay_string): d = matcher.groupdict() facet_name = d['facet'] verticies = d['verts'] neighboring_facets = d['neigh'] cur_face = face(facet_name) self.faces[facet_name] = cur_face for v in grid.vert_re.findall(verticies): vertex_index = int(v[1:]) cur_face.add_vert(vertex_index) self.facets_for_point[vertex_index].append(cur_face) nghbrs = [(facet_name, i) for i in neighboring_facets.split()] facet_to_facets.extend(nghbrs) for rel in facet_to_facets: if rel[1] in self.faces: self.faces[rel[0]].add_neighbor(self.faces[rel[1]]) smblog.debug('end') def __str__(self): r = '' assert( len(self.points) == len(self.q) ) for c, i in enumerate(zip(self.points, self.q)): r += "%d %r: %0.4f" % (c,i[0], i[1]) facet_str = ", ".join([f.name for f in self.facets_for_point[c]]) r += " faces: [%s]" % facet_str r += "\n" if self.faces: for v in self.faces.itervalues(): r += "%s\n" % v return r