CGAL alpha形狀python簡單的例子出錯了？

Question

我希望使用CGAL來獲得alpha形狀。

@sloriot提供an extremely relevant script和我的定製後：

from sys import * 
path.append("../../cgal_package") 

from CGAL.Alpha_shapes_2 import * 
from CGAL.Triangulations_2 import Delaunay_triangulation_2 
from CGAL.Kernel import * 

from random import * 

import matplotlib.pyplot as plt 
from matplotlib.font_manager import FontProperties 

import constants 

def Point_2_str(self): 
    return "Point_2"+str((self.x(), self.y())) 
# now we turn it into a member function 
Point_2.__str__ = Point_2_str 


def show_alpha_values(AS): 
    print "Alpha spectrum" 
    for alpha_value in AS.alpha: 
     print alpha_value 


def read_points(file): 
    result = [] 
    dataFile = open(file, 'r') 
    for i, line in enumerate(dataFile): 
     coordinateList = [float(x) for x in line.strip().split()] 
     for j in range(0, len(coordinateList), 2): 
      result.append(Point_2(coordinateList[j], coordinateList[j+1])) 
    dataFile.close() 
    return result 


def getAlphaShape(): 
    L =[] 
    verbose = True 
    list_of_points = read_points(constants.PROJECT_PATH + '\\data\\clusters.txt') 

    a = Alpha_shape_2() 
    a.make_alpha_shape(list_of_points) 
    a.set_mode(Alpha_shape_2.Mode.REGULARIZED) 
    a.set_alpha(1000) 
    alpha_shape_edges = [] 
    alpha_shape_vertices = [] 
    for it in a.alpha_shape_edges: 
     alpha_shape_edges.append(a.segment(it)) 
    for it in a.alpha_shape_vertices: 
     alpha_shape_vertices.append(it) 

    _showAlphaShape(list_of_points, alpha_shape_vertices) 

    print "alpha_shape_edges" 
    print len(alpha_shape_edges) 
    print "alpha_shape_vertices"  
    print len(alpha_shape_vertices) 
    print "Optimal alpha: " 
    print a.find_optimal_alpha(2).next() 


def _showAlphaShape(points, vertices): 
    fig = plt.figure() 
    axes = fig.add_axes([0.1, 0.1, 0.8, 0.8]) # left, bottom, width, height (range 0 to 1) 
    axes.axis('equal') 
    axes.set_xlabel(r'$x (m)$') 
    axes.set_ylabel(r'$y (m)$') 
    axes.set_title(r'$\alpha$-shape of clusters') 
    # draw cluster points 
    x = [pt.x() for pt in points] 
    y = [pt.y() for pt in points] 
    axes.scatter(x, y, s=1) 
    # draw alpha shape 
    for i in range(len(vertices)-1): 
     x1 = vertices[i].point()[0] 
     x2 = vertices[i+1].point()[0] 
     y1 = vertices[i].point()[1] 
     y2 = vertices[i+1].point()[1] 
     axes.plot([[x1, x2], [y1, y2]], color='b') 
    fontP = FontProperties() 
    fontP.set_size('7') 
    axes.legend(loc=3, prop=fontP) 
    fig.savefig(constants.PROJECT_PATH + '\\data\\1.svg') 

當我運行它，我得到

藍色部分顯然是不的字母形狀。 哪裏出錯了？

Answer 1

查看從your detailed question here。我高度懷疑這是由於您的CGAL和Python包之間不匹配造成的。