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here is my python code, it does not intersect and when I plot this in google map , I see the intersection. shapely.geometry is in Cartesian plane, how you are solving this? 

l = "40.65:-114.07 40.21:-112.96 40:-112.66 39.4:-112.7 39.39:-113.28 39.68:-113.94 40.42:-114.26 40.6:-114.22"
    points = [[float(x) for x in c.split(":")] for c in l.split(" ")]
    print(points)
    polygon = Polygon(points)
    path = LineString([(42.049999,-96.25), (38.0880979565,-119.609216457)])
    if path.intersects(polygon):
        print("intersect")

here is the intersection on google map

here is my code for google map:

https://gist.github.com/anonymous/8393151

probash
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1 Answers1

4

With your solution:

print polygon.wkt
'POLYGON ((40.6499999999999986 -114.0699999999999932, 40.2100000000000009 -112.9599999999999937, 40.0000000000000000 -112.6599999999999966, 39.3999999999999986 -112.7000000000000028, 39.3900000000000006 -113.2800000000000011, 39.6799999999999997 -113.9399999999999977, 40.4200000000000017 -114.2600000000000051, 40.6000000000000014 -114.2199999999999989, 40.6499999999999986 -114.0699999999999932))'
path = LineString([(42.049999,-96.25), (38.0880979565,-119.609216457)])
print path.wkt
'LINESTRING (42.0499989999999997 -96.2500000000000000, 38.0880979565000004 -119.6092164570000023)'

The result in Google Maps is really meaningless (obtained image with the OpenLayers plugin of QGIS)

enter image description here

So, it seems to me that there is an inversion in the coordinates of the points:

 40.65 is the latitude of the point -> y
 -114.07 is the longitude of the point -> x

and

from shapely.geometry import Polygon, LineString
l = "40.65:-114.07 40.21:-112.96 40:-112.66 39.4:-112.7 39.39:-113.28 39.68:-113.94 40.42:-114.26 40.6:-114.22"
# swapping the coordinates:
points = [[float(x) for x in c.split(":")[::-1]] for c in l.split(" ")]
print points
[-114.06999999999999, 40.649999999999999], [-112.95999999999999, 40.210000000000001], [-112.66, 40.0], [-112.7, 39.399999999999999], [-113.28, 39.390000000000001], [-113.94, 39.68], [-114.26000000000001, 40.420000000000002], [-114.22, 40.600000000000001]]
polygon = Polygon(points)
path = LineString([(-96.25,42.049999), (-119.609216457,38.0880979565)])
path.intersects(polygon)
False

I can plot the geometries in Google Maps and I see no intersection:

enter image description here

gene
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