From: Vivien Maisonneuve Date: Fri, 11 Jul 2014 13:41:26 +0000 (+0200) Subject: Private methods to sort points in a polygon, untested X-Git-Tag: 1.0~131 X-Git-Url: https://scm.cri.mines-paristech.fr/git/linpy.git/commitdiff_plain/45951a9f688b1a3dda02979cacb93747b1422709?ds=inline;hp=3d17926f6a9051fd4b3a2c19b756849103592bd9 Private methods to sort points in a polygon, untested --- diff --git a/pypol/coordinates.py b/pypol/coordinates.py index eb8e78c..9e46673 100644 --- a/pypol/coordinates.py +++ b/pypol/coordinates.py @@ -171,7 +171,7 @@ class Vector(Coordinates): """ if not isinstance(other, Vector): raise TypeError('argument must be a Vector instance') - cosinus = self.dot(other) / (self.norm() * other.norm()) + cosinus = self.dot(other) / (self.norm()*other.norm()) return math.acos(cosinus) def cross(self, other): diff --git a/pypol/polyhedra.py b/pypol/polyhedra.py index db99753..3db8f40 100644 --- a/pypol/polyhedra.py +++ b/pypol/polyhedra.py @@ -1,5 +1,6 @@ import functools +import math import numbers from . import islhelper @@ -195,19 +196,55 @@ class Polyhedron(Domain): for inequality in self.inequalities: constraints.append(sympy.Ge(inequality.tosympy(), 0)) return sympy.And(*constraints) - + + @classmethod + def _sort_polygon_2d(cls, points): + if len(points) <= 3: + return points + o = sum((Vector(point) for point in points)) / len(points) + o = Point(o.coordinates()) + angles = {} + for m in points: + om = Vector(o, m) + dx, dy = (coordinate for symbol, coordinates in om.coordinates()) + angle = math.atan2(dy, dx) + angles[m] = angle + return sorted(points, key=angles.get) + + @classmethod + def _sort_polygon_3d(cls, points): + if len(points) <= 3: + return points + o = sum((Vector(point) for point in points)) / len(points) + o = Point(o.coordinates()) + a, b = points[:2] + oa = Vector(o, a) + ob = Vector(o, b) + norm_oa = oa.norm() + u = (oa.cross(ob)).asunit() + angles = {a: 0.} + for m in points[1:]: + om = Vector(o, m) + normprod = norm_oa * om.norm() + cosinus = oa.dot(om) / normprod + sinus = u.dot(oa.cross(om)) / normprod + angle = math.acos(cosinus) + angle = math.copysign(angle, sinus) + angles[m] = angle + return sorted(points, key=angles.get) + def plot(self): import matplotlib.pyplot as plt from matplotlib.path import Path import matplotlib.patches as patches - + if len(self.symbols)> 3: raise TypeError - + elif len(self.symbols) == 2: verts = self.vertices() points = [] - codes = [Path.MOVETO] + codes = [Path.MOVETO] for vert in verts: pairs = () for sym in sorted(vert, key=Symbol.sortkey): @@ -229,10 +266,10 @@ class Polyhedron(Domain): ax.set_xlim(-5,5) ax.set_ylim(-5,5) plt.show() - + elif len(self.symbols)==3: return 0 - + return points