1

I am working in Python 3.7 using ogr to check if a point is inside a polygon. Here I put the code. The result in geom is not compatible with the tuple list data type used by the point_inside function.

How can this information be made compatible?

from osgeo import ogr

def point_inside_polygon(x,y,poly):

    n = len(poly)
    inside =False

    p1x,p1y = poly[0]
    for i in range(n+1):
        p2x,p2y = poly[i % n]
        if y > min(p1y,p2y):
            if y <= max(p1y,p2y):
                if x <= max(p1x,p2x):
                    if p1y != p2y:
                        xinters = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                    if p1x == p2x or x <= xinters:
                        inside = not inside
        p1x,p1y = p2x,p2y

    return inside
 
file = ogr.Open("C:/Programas/Python/salida.shp/MSK_CLOUDS_B00.shp")
shape = file.GetLayer()
feature = shape.GetFeature(0)
 
for feature in shape:

 #geom  = feature.GetGeometryRef() 
 geom = feature.geometry()
  
 print (geom)
  
  
 print(point_inside_polygon(-90.2,14.3,geom) )
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0

Why not use the contains methods on the polygon (geom)?

p1 = Point(-90.2, 14.3)

for feature in shape: 
     geom = feature.geometry()

     if geom.contains(p1):
          print(geom)
2
  • It gives me the error: File "C:/Programas/Python/puntodentrodes22.py", line 36, in <module> if geom.contains(p1): AttributeError: 'Geometry' object has no attribute 'contains' – Jose Cordovez Feb 10 at 17:31
  • I'm not sure what returns: feature.geometry () – Jose Cordovez Feb 10 at 17:35
0

EUREKA

for feature in shape:
  
 #geom  = feature.GetGeometryRef() 
 geom = feature.geometry()
 json_geom = feature.ExportToJson()

  
 geom = json.loads(json_geom)
  
 poly=(geom['geometry'] ['coordinates'])
  
 poly_a=(poly[0])
 
 print(point_inside_polygon(x,y,poly_a))
 
 print ("------")

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