source: anuga_core/source/anuga/utilities/test_polygon.py @ 5119

#!/usr/bin/env python


import unittest
from Numeric import zeros, array, allclose
from math import sqrt, pi
from anuga.utilities.numerical_tools import ensure_numeric
from anuga.utilities.system_tools import get_pathname_from_package

from polygon import *
from anuga.coordinate_transforms.geo_reference import Geo_reference
from anuga.geospatial_data.geospatial_data import Geospatial_data

def test_function(x, y):
    return x+y

class Test_Polygon(unittest.TestCase):
    def setUp(self):
        pass

    def tearDown(self):
        pass


    def test_that_C_extension_compiles(self):
        FN = 'polygon_ext.c'
        try:
            import polygon_ext
        except:
            from compile import compile

            try:
                compile(FN)
            except:
                raise 'Could not compile %s' %FN
            else:
                import polygon_ext


    #Polygon stuff
    def test_polygon_function_constants(self):
        p1 = [[0,0], [10,0], [10,10], [0,10]]
        p2 = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]

        f = Polygon_function( [(p1, 1.0)] )
        z = f([5, 5, 27, 35], [5, 9, 8, -5]) #Two first inside p1
        assert allclose(z, [1,1,0,0])


        f = Polygon_function( [(p2, 2.0)] )
        z = f([5, 5, 27, 35], [5, 9, 8, -5]) # First and last inside p2
        assert allclose(z, [2,0,0,2])


        #Combined
        f = Polygon_function( [(p1, 1.0), (p2, 2.0)] )
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert allclose(z, [2,1,0,2])

    def test_polygon_function_csvfile(self):
        from os import sep, getenv


        # Get path where this test is run
        path = get_pathname_from_package('anuga.utilities')

        # Form absolute filename and read
        filename = path + sep +  'mainland_only.csv'
        p1 = read_polygon(filename)        

        f = Polygon_function( [(p1, 10.0)] )
        z = f([430000,480000], [490000,7720000]) # first outside, second inside
        
        assert allclose(z, [0,10])

    def test_polygon_function_georef(self):
        """Check that georeferencing works
        """

        from anuga.coordinate_transforms.geo_reference import Geo_reference

        geo = Geo_reference(56, 200, 1000)

        # Make points 'absolute'
        p1 = [[200,1000], [210,1000], [210,1010], [200,1010]]
        p2 = [[200,1000], [210,1010], [215,1005], [220, 1010], [225,1000],
              [230,1010], [240,990]]

        f = Polygon_function( [(p1, 1.0)], geo_reference=geo)
        z = f([5, 5, 27, 35], [5, 9, 8, -5]) #Two first inside p1

        assert allclose(z, [1,1,0,0])


        f = Polygon_function( [(p2, 2.0)], geo_reference=geo)
        z = f([5, 5, 27, 35], [5, 9, 8, -5]) #First and last inside p2
        assert allclose(z, [2,0,0,2])


        # Combined
        f = Polygon_function( [(p1, 1.0), (p2, 2.0)], geo_reference=geo)
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert allclose(z, [2,1,0,2])


        # Check that it would fail without geo
        f = Polygon_function( [(p1, 1.0), (p2, 2.0)])
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert not allclose(z, [2,1,0,2])        



    def test_polygon_function_callable(self):
        """Check that values passed into Polygon_function can be callable
        themselves.
        """
        p1 = [[0,0], [10,0], [10,10], [0,10]]
        p2 = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]

        f = Polygon_function( [(p1, test_function)] )
        z = f([5, 5, 27, 35], [5, 9, 8, -5]) #Two first inside p1
        assert allclose(z, [10,14,0,0])

        # Combined
        f = Polygon_function( [(p1, test_function), (p2, 2.0)] )
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert allclose(z, [2,14,0,2])


        # Combined w default
        f = Polygon_function( [(p1, test_function), (p2, 2.0)], default = 3.14)
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert allclose(z, [2,14,3.14,2])


        # Combined w default func
        f = Polygon_function( [(p1, test_function), (p2, 2.0)],
                              default = test_function)
        z = f([5, 5, 27, 35], [5, 9, 8, -5])
        assert allclose(z, [2,14,35,2])



    def test_point_on_line(self):

        #Endpoints first
        assert point_on_line( 0, 0, 0,0, 1,0 )
        assert point_on_line( 1, 0, 0,0, 1,0 )

        #Then points on line
        assert point_on_line( 0.5, 0, 0,0, 1,0 )
        assert point_on_line( 0, 0.5, 0,1, 0,0 )
        assert point_on_line( 1, 0.5, 1,1, 1,0 )
        assert point_on_line( 0.5, 0.5, 0,0, 1,1 )

        #Then points not on line
        assert not point_on_line( 0.5, 0, 0,1, 1,1 )
        assert not point_on_line( 0, 0.5, 0,0, 1,1 )

        #From real example that failed
        assert not point_on_line( 40,50, 40,20, 40,40 )


        #From real example that failed
        assert not point_on_line( 40,19, 40,20, 40,40 )




    def test_is_inside_polygon_main(self):


        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,1], [0,1]]

        assert is_inside_polygon( (0.5, 0.5), polygon )
        assert not is_inside_polygon( (0.5, 1.5), polygon )
        assert not is_inside_polygon( (0.5, -0.5), polygon )
        assert not is_inside_polygon( (-0.5, 0.5), polygon )
        assert not is_inside_polygon( (1.5, 0.5), polygon )

        #Try point on borders
        assert is_inside_polygon( (1., 0.5), polygon, closed=True)
        assert is_inside_polygon( (0.5, 1), polygon, closed=True)
        assert is_inside_polygon( (0., 0.5), polygon, closed=True)
        assert is_inside_polygon( (0.5, 0.), polygon, closed=True)

        assert not is_inside_polygon( (0.5, 1), polygon, closed=False)
        assert not is_inside_polygon( (0., 0.5), polygon, closed=False)
        assert not is_inside_polygon( (0.5, 0.), polygon, closed=False)
        assert not is_inside_polygon( (1., 0.5), polygon, closed=False)


    def test_inside_polygon_main(self):

        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,1], [0,1]]        

        #From real example (that failed)
        polygon = [[20,20], [40,20], [40,40], [20,40]]
        points = [ [40, 50] ]
        res = inside_polygon(points, polygon)
        assert len(res) == 0

        polygon = [[20,20], [40,20], [40,40], [20,40]]
        points = [ [25, 25], [30, 20], [40, 50], [90, 20], [40, 90] ]
        res = inside_polygon(points, polygon)
        assert len(res) == 2
        assert allclose(res, [0,1])



        #More convoluted and non convex polygon
        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        assert is_inside_polygon( (0.5, 0.5), polygon )
        assert is_inside_polygon( (1, -0.5), polygon )
        assert is_inside_polygon( (1.5, 0), polygon )

        assert not is_inside_polygon( (0.5, 1.5), polygon )
        assert not is_inside_polygon( (0.5, -0.5), polygon )


        #Very convoluted polygon
        polygon = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]
        assert is_inside_polygon( (5, 5), polygon )
        assert is_inside_polygon( (17, 7), polygon )
        assert is_inside_polygon( (27, 2), polygon )
        assert is_inside_polygon( (35, -5), polygon )
        assert not is_inside_polygon( (15, 7), polygon )
        assert not is_inside_polygon( (24, 3), polygon )
        assert not is_inside_polygon( (25, -10), polygon )



        #Another combination (that failed)
        polygon = [[0,0], [10,0], [10,10], [0,10]]
        assert is_inside_polygon( (5, 5), polygon )
        assert is_inside_polygon( (7, 7), polygon )
        assert not is_inside_polygon( (-17, 7), polygon )
        assert not is_inside_polygon( (7, 17), polygon )
        assert not is_inside_polygon( (17, 7), polygon )
        assert not is_inside_polygon( (27, 8), polygon )
        assert not is_inside_polygon( (35, -5), polygon )




        #Multiple polygons

        polygon = [[0,0], [1,0], [1,1], [0,1], [0,0],
                   [10,10], [11,10], [11,11], [10,11], [10,10]]
        assert is_inside_polygon( (0.5, 0.5), polygon )
        assert is_inside_polygon( (10.5, 10.5), polygon )

        #FIXME: Fails if point is 5.5, 5.5
        assert not is_inside_polygon( (0, 5.5), polygon )

        #Polygon with a hole
        polygon = [[-1,-1], [2,-1], [2,2], [-1,2], [-1,-1],
                   [0,0], [1,0], [1,1], [0,1], [0,0]]

        assert is_inside_polygon( (0, -0.5), polygon )
        assert not is_inside_polygon( (0.5, 0.5), polygon )



    def test_duplicate_points_being_ok(self):


        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,0], [1,0], [1,1], [0,1], [0,0]]

        assert is_inside_polygon( (0.5, 0.5), polygon )
        assert not is_inside_polygon( (0.5, 1.5), polygon )
        assert not is_inside_polygon( (0.5, -0.5), polygon )
        assert not is_inside_polygon( (-0.5, 0.5), polygon )
        assert not is_inside_polygon( (1.5, 0.5), polygon )

        #Try point on borders
        assert is_inside_polygon( (1., 0.5), polygon, closed=True)
        assert is_inside_polygon( (0.5, 1), polygon, closed=True)
        assert is_inside_polygon( (0., 0.5), polygon, closed=True)
        assert is_inside_polygon( (0.5, 0.), polygon, closed=True)

        assert not is_inside_polygon( (0.5, 1), polygon, closed=False)
        assert not is_inside_polygon( (0., 0.5), polygon, closed=False)
        assert not is_inside_polygon( (0.5, 0.), polygon, closed=False)
        assert not is_inside_polygon( (1., 0.5), polygon, closed=False)

        #From real example
        polygon = [[20,20], [40,20], [40,40], [20,40]]
        points = [ [40, 50] ]
        res = inside_polygon(points, polygon)
        assert len(res) == 0

        

    def test_inside_polygon_vector_version(self):
        #Now try the vector formulation returning indices
        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        points = [ [0.5, 0.5], [1, -0.5], [1.5, 0], [0.5, 1.5], [0.5, -0.5]]
        res = inside_polygon( points, polygon, verbose=False )

        assert allclose( res, [0,1,2] )

    def test_outside_polygon(self):
        U = [[0,0], [1,0], [1,1], [0,1]] #Unit square    

        assert not is_outside_polygon( [0.5, 0.5], U )
        #evaluate to False as the point 0.5, 0.5 is inside the unit square
        
        assert is_outside_polygon( [1.5, 0.5], U )
        #evaluate to True as the point 1.5, 0.5 is outside the unit square
        
        indices = outside_polygon( [[0.5, 0.5], [1, -0.5], [0.3, 0.2]], U )
        assert allclose( indices, [1] )
        
        #One more test of vector formulation returning indices
        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        points = [ [0.5, 0.5], [1, -0.5], [1.5, 0], [0.5, 1.5], [0.5, -0.5]]
        res = outside_polygon( points, polygon )

        assert allclose( res, [3, 4] )



        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        points = [ [0.5, 1.4], [0.5, 0.5], [1, -0.5], [1.5, 0], [0.5, 1.5], [0.5, -0.5]]
        res = outside_polygon( points, polygon )

        assert allclose( res, [0, 4, 5] )        
     
    def test_outside_polygon2(self):
        U = [[0,0], [1,0], [1,1], [0,1]] #Unit square    
   
        assert not outside_polygon( [0.5, 1.0], U, closed = True )
        #evaluate to False as the point 0.5, 1.0 is inside the unit square
        
        assert is_outside_polygon( [0.5, 1.0], U, closed = False )
        #evaluate to True as the point 0.5, 1.0 is outside the unit square

    def test_all_outside_polygon(self):
        """Test case where all points are outside poly
        """
        
        U = [[0,0], [1,0], [1,1], [0,1]] #Unit square    

        points = [[2,2], [1,3], [-1,1], [0,2]] #All outside


        indices, count = separate_points_by_polygon(points, U)
        #print indices, count
        assert count == 0 #None inside
        assert allclose(indices, [3,2,1,0])

        indices = outside_polygon(points, U, closed = True)
        assert allclose(indices, [0,1,2,3])

        indices = inside_polygon(points, U, closed = True)
        assert allclose(indices, [])                


    def test_all_inside_polygon(self):
        """Test case where all points are inside poly
        """
        
        U = [[0,0], [1,0], [1,1], [0,1]] #Unit square    

        points = [[0.5,0.5], [0.2,0.3], [0,0.5]] #All inside (or on edge)


        indices, count = separate_points_by_polygon(points, U)
        assert count == 3 #All inside
        assert allclose(indices, [0,1,2])

        indices = outside_polygon(points, U, closed = True)
        assert allclose(indices, [])

        indices = inside_polygon(points, U, closed = True)
        assert allclose(indices, [0,1,2])
        

    def test_separate_points_by_polygon(self):
        U = [[0,0], [1,0], [1,1], [0,1]] #Unit square    

        indices, count = separate_points_by_polygon( [[0.5, 0.5], [1, -0.5], [0.3, 0.2]], U )
        assert allclose( indices, [0,2,1] )
        assert count == 2
        
        #One more test of vector formulation returning indices
        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        points = [ [0.5, 0.5], [1, -0.5], [1.5, 0], [0.5, 1.5], [0.5, -0.5]]
        res, count = separate_points_by_polygon( points, polygon )

        assert allclose( res, [0,1,2,4,3] )
        assert count == 3


        polygon = [[0,0], [1,0], [0.5,-1], [2, -1], [2,1], [0,1]]
        points = [ [0.5, 1.4], [0.5, 0.5], [1, -0.5], [1.5, 0], [0.5, 1.5], [0.5, -0.5]]
        res, count = separate_points_by_polygon( points, polygon )

        assert allclose( res, [1,2,3,5,4,0] )        
        assert count == 3
        

    def test_populate_polygon(self):

        polygon = [[0,0], [1,0], [1,1], [0,1]]
        points = populate_polygon(polygon, 5)

        assert len(points) == 5
        for point in points:
            assert is_inside_polygon(point, polygon)


        #Very convoluted polygon
        polygon = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]

        points = populate_polygon(polygon, 5)

        assert len(points) == 5
        for point in points:
            assert is_inside_polygon(point, polygon)


    def test_populate_polygon_with_exclude(self):
        

        polygon = [[0,0], [1,0], [1,1], [0,1]]
        ex_poly = [[0,0], [0.5,0], [0.5, 0.5], [0,0.5]] #SW quarter
        points = populate_polygon(polygon, 5, exclude = [ex_poly])

        assert len(points) == 5
        for point in points:
            assert is_inside_polygon(point, polygon)
            assert not is_inside_polygon(point, ex_poly)            


        #overlap
        polygon = [[0,0], [1,0], [1,1], [0,1]]
        ex_poly = [[-1,-1], [0.5,0], [0.5, 0.5], [-1,0.5]]
        points = populate_polygon(polygon, 5, exclude = [ex_poly])

        assert len(points) == 5
        for point in points:
            assert is_inside_polygon(point, polygon)
            assert not is_inside_polygon(point, ex_poly)                        
        
        #Multiple
        polygon = [[0,0], [1,0], [1,1], [0,1]]
        ex_poly1 = [[0,0], [0.5,0], [0.5, 0.5], [0,0.5]] #SW quarter
        ex_poly2 = [[0.5,0.5], [0.5,1], [1, 1], [1,0.5]] #NE quarter        
        
        points = populate_polygon(polygon, 20, exclude = [ex_poly1, ex_poly2])

        assert len(points) == 20
        for point in points:
            assert is_inside_polygon(point, polygon)
            assert not is_inside_polygon(point, ex_poly1)
            assert not is_inside_polygon(point, ex_poly2)                                
        

        #Very convoluted polygon
        polygon = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]
        ex_poly = [[-1,-1], [5,0], [5, 5], [-1,5]]
        points = populate_polygon(polygon, 20, exclude = [ex_poly])
        
        assert len(points) == 20
        for point in points:
            assert is_inside_polygon(point, polygon)
            assert not is_inside_polygon(point, ex_poly), '%s' %str(point)                        


    def test_populate_polygon_with_exclude2(self):
        

        min_outer = 0 
        max_outer = 1000
        polygon_outer = [[min_outer,min_outer],[max_outer,min_outer],
                   [max_outer,max_outer],[min_outer,max_outer]]

        delta = 10
        min_inner1 = min_outer + delta
        max_inner1 = max_outer - delta
        inner1_polygon = [[min_inner1,min_inner1],[max_inner1,min_inner1],
                   [max_inner1,max_inner1],[min_inner1,max_inner1]]
      
        
        density_inner2 = 1000 
        min_inner2 = min_outer +  2*delta
        max_inner2 = max_outer -  2*delta
        inner2_polygon = [[min_inner2,min_inner2],[max_inner2,min_inner2],
                   [max_inner2,max_inner2],[min_inner2,max_inner2]]      
        
        points = populate_polygon(polygon_outer, 20, exclude = [inner1_polygon, inner2_polygon])

        assert len(points) == 20
        for point in points:
            assert is_inside_polygon(point, polygon_outer)
            assert not is_inside_polygon(point, inner1_polygon)
            assert not is_inside_polygon(point, inner2_polygon)                                
        

        #Very convoluted polygon
        polygon = [[0,0], [10,10], [15,5], [20, 10], [25,0], [30,10], [40,-10]]
        ex_poly = [[-1,-1], [5,0], [5, 5], [-1,5]]
        points = populate_polygon(polygon, 20, exclude = [ex_poly])
        
        assert len(points) == 20
        for point in points:
            assert is_inside_polygon(point, polygon)
            assert not is_inside_polygon(point, ex_poly), '%s' %str(point)                        

    def test_point_in_polygon(self):
        polygon = [[0,0], [1,0], [1,1], [0,1]]
        point = point_in_polygon(polygon)
        assert is_inside_polygon(point, polygon)

        #this may get into a vicious loop
        #polygon = [[1e32,1e54], [1,0], [1,1], [0,1]]
        
        polygon = [[1e15,1e7], [1,0], [1,1], [0,1]]
        point = point_in_polygon(polygon)
        assert is_inside_polygon(point, polygon)


        polygon = [[0,0], [1,0], [1,1], [1e8,1e8]]
        point = point_in_polygon(polygon)
        assert is_inside_polygon(point, polygon)

        
        polygon = [[1e32,1e54], [-1e32,1e54], [1e32,-1e54]]
        point = point_in_polygon(polygon)
        assert is_inside_polygon(point, polygon)

        
        polygon = [[1e18,1e15], [1,0], [0,1]]
        point = point_in_polygon(polygon)
        assert is_inside_polygon(point, polygon)

    def test_in_and_outside_polygon_main(self):


        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,1], [0,1]]

        inside, outside =  in_and_outside_polygon( (0.5, 0.5), polygon )
        assert inside[0] == 0
        assert len(outside) == 0
        
        inside, outside =  in_and_outside_polygon(  (1., 0.5), polygon, closed=True)
        assert inside[0] == 0
        assert len(outside) == 0
        
        inside, outside =  in_and_outside_polygon(  (1., 0.5), polygon, closed=False)
        assert len(inside) == 0
        assert outside[0] == 0

        points =  [(1., 0.25),(1., 0.75) ]
        inside, outside =  in_and_outside_polygon( points, polygon, closed=True)
        assert (inside, [0,1])
        assert len(outside) == 0
        
        inside, outside =  in_and_outside_polygon( points, polygon, closed=False)
        assert len(inside) == 0
        assert (outside, [0,1])

       
        points =  [(100., 0.25),(0.5, 0.5) ] 
        inside, outside =  in_and_outside_polygon( points, polygon)
        assert (inside, [1])
        assert outside[0] == 0
        
        points =  [(100., 0.25),(0.5, 0.5), (39,20), (0.6,0.7),(56,43),(67,90) ] 
        inside, outside =  in_and_outside_polygon( points, polygon)
        assert (inside, [1,3])
        assert (outside, [0,2,4,5])
        
    def zzztest_inside_polygon_main(self):  
        print "inside",inside
        print "outside",outside
        
        assert not inside_polygon( (0.5, 1.5), polygon )
        assert not inside_polygon( (0.5, -0.5), polygon )
        assert not inside_polygon( (-0.5, 0.5), polygon )
        assert not inside_polygon( (1.5, 0.5), polygon )

        #Try point on borders
        assert inside_polygon( (1., 0.5), polygon, closed=True)
        assert inside_polygon( (0.5, 1), polygon, closed=True)
        assert inside_polygon( (0., 0.5), polygon, closed=True)
        assert inside_polygon( (0.5, 0.), polygon, closed=True)

        assert not inside_polygon( (0.5, 1), polygon, closed=False)
        assert not inside_polygon( (0., 0.5), polygon, closed=False)
        assert not inside_polygon( (0.5, 0.), polygon, closed=False)
        assert not inside_polygon( (1., 0.5), polygon, closed=False)



        #From real example (that failed)
        polygon = [[20,20], [40,20], [40,40], [20,40]]
        points = [ [40, 50] ]
        res = inside_polygon(points, polygon)
        assert len(res) == 0

        polygon = [[20,20], [40,20], [40,40], [20,40]]
        points = [ [25, 25], [30, 20], [40, 50], [90, 20], [40, 90] ]
        res = inside_polygon(points, polygon)
        assert len(res) == 2
        assert allclose(res, [0,1])

    def test_polygon_area(self):

        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,1], [0,1]]
        assert polygon_area(polygon) == 1

        #Simple case: Polygon is a rectangle
        polygon = [[0,0], [1,0], [1,4], [0,4]]
        assert polygon_area(polygon) == 4

        #Simple case: Polygon is a unit triangle
        polygon = [[0,0], [1,0], [0,1]]
        assert polygon_area(polygon) == 0.5

        #Simple case: Polygon is a diamond
        polygon = [[0,0], [1,1], [2,0], [1, -1]]
        assert polygon_area(polygon) == 2.0

    def test_poly_xy(self):
 
        #Simplest case: Polygon is the unit square
        polygon = [[0,0], [1,0], [1,1], [0,1]]
        x, y = poly_xy(polygon)
        assert len(x) == len(polygon)+1
        assert len(y) == len(polygon)+1
        assert x[0] == 0
        assert x[1] == 1
        assert x[2] == 1
        assert x[3] == 0
        assert y[0] == 0
        assert y[1] == 0
        assert y[2] == 1
        assert y[3] == 1

        #Arbitrary polygon
        polygon = [[1,5], [1,1], [100,10], [1,10], [3,6]]
        x, y = poly_xy(polygon)
        assert len(x) == len(polygon)+1
        assert len(y) == len(polygon)+1
        assert x[0] == 1
        assert x[1] == 1
        assert x[2] == 100
        assert x[3] == 1
        assert x[4] == 3
        assert y[0] == 5
        assert y[1] == 1
        assert y[2] == 10
        assert y[3] == 10
        assert y[4] == 6

    # Disabled    
    def xtest_plot_polygons(self):
        
        import os
        
        #Simplest case: Polygon is the unit square
        polygon1 = [[0,0], [1,0], [1,1], [0,1]]
        polygon2 = [[1,1], [2,1], [3,2], [2,2]]
        v = plot_polygons([polygon1, polygon2],'test1')
        assert len(v) == 4
        assert v[0] == 0
        assert v[1] == 3
        assert v[2] == 0
        assert v[3] == 2

        #Another case
        polygon3 = [[1,5], [10,1], [100,10], [50,10], [3,6]]
        v = plot_polygons([polygon2,polygon3],'test2')
        assert len(v) == 4
        assert v[0] == 1
        assert v[1] == 100
        assert v[2] == 1
        assert v[3] == 10

        os.remove('test1.png')
        os.remove('test2.png')

        
    def test_inside_polygon_geospatial(self):


        polygon_absolute = [[0,0], [1,0], [1,1], [0,1]]
        poly_geo_ref = Geo_reference(57,100,100)
        



        #Simplest case: Polygon is the unit square
        polygon_absolute = [[0,0], [1,0], [1,1], [0,1]]
        poly_geo_ref = Geo_reference(57,100,100)
        polygon = poly_geo_ref.change_points_geo_ref(polygon_absolute)
        poly_spatial = Geospatial_data(polygon,
                                       geo_reference=poly_geo_ref)
        
        points_absolute = (0.5, 0.5)
        points_geo_ref = Geo_reference(57,78,-56)
        points = points_geo_ref.change_points_geo_ref(points_absolute)
        points_spatial = Geospatial_data(points,
                                         geo_reference=points_geo_ref) 
        
        assert is_inside_polygon(points_absolute, polygon_absolute)
        assert is_inside_polygon(ensure_numeric(points_absolute),
                                 ensure_numeric(polygon_absolute))
        assert is_inside_polygon(points_absolute, poly_spatial)
        assert is_inside_polygon(points_spatial, poly_spatial)
        assert is_inside_polygon(points_spatial, polygon_absolute)

        assert is_inside_polygon(points_absolute, polygon_absolute)


    def NOtest_decimate_polygon(self):

        polygon = [[0,0], [10,10], [15,5], [20, 10],
                   [25,0], [30,10], [40,-10], [35, -5]]

        #plot_polygons([polygon], figname='test')
        
        dpoly = decimate_polygon(polygon, factor=2)

        print dpoly
        
        assert len(dpoly)*2==len(polygon)

        minx = maxx = polygon[0][0]
        miny = maxy = polygon[0][1]
        for point in polygon[1:]:
            x, y = point
            
            if x < minx: minx = x
            if x > maxx: maxx = x
            if y < miny: miny = y
            if y > maxy: maxy = y
            

        assert [minx, miny] in polygon
        print minx, maxy
        assert [minx, maxy] in polygon
        assert [maxx, miny] in polygon
        assert [maxx, maxy] in polygon                
        

        
#-------------------------------------------------------------
if __name__ == "__main__":
    suite = unittest.makeSuite(Test_Polygon,'test')
    #suite = unittest.makeSuite(Test_Polygon,'test_inside_polygon_geo_ref')
    runner = unittest.TextTestRunner()
    runner.run(suite)