combine two loops in python

Question

suppose to have two polygons p1 and p2, where p2 is completely inside p1

p1 = [(0, 10), (10, 10), (10, 0), (0, 0)]
p2 = [(2, 6), (6, 6), (6, 2), (2, 2)]

degree_of_contact = 0

xyarrays = [p1,p2]
p1_degree_of_contact = 0
for x,y in xyarrays[0]:
        if point_inside_polygon(x,y,xyarrays[1]):
            p1_degree_of_contact += 1

p2_degree_of_contact = 0
for x,y in xyarrays[1]:
        if point_inside_polygon(x,y,xyarrays[0]):
            p2_degree_of_contact += 1

degree_of_contact = p1_degree_of_contact + p2_degree_of_contact

where point_inside_polygon is to deciding if a point is inside (True, False otherwise) a polygon, where poly is a list of pairs (x,y) containing the coordinates of the polygon's vertices. The algorithm is called the "Ray Casting Method

i wish to combine in an elegant way (line coding save) both loops in one.

Since I think your work is relevant, take a look at numpy which has built in support for vectors and matrices. There are nice tricks you can do there (like vectorized loops) that are purely written in C and are very fast. And its not only for speed: there are tons of built-in math methods which should make your life easier for such problems. scipy.org/Tentative_NumPy_Tutorial — entropiece
– entropiece, Commented Mar 6, 2013 at 18:13

Andrew Clark · Accepted Answer · 2013-03-06 18:09:05Z

3

The following should work:

degree_of_contact = 0
for tmp1, tmp2 in [(p1, p2), (p2, p1)]:
    for x,y in tmp1:
        if point_inside_polygon(x, y, tmp2):
            degree_of_contact += 1

answered Mar 6, 2013 at 18:09

Andrew Clark

210k36 gold badges285 silver badges310 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

John La Rooy · Accepted Answer · 2013-03-06 18:18:27Z

1

degree_of_contact = sum(point_inside_polygon(x, y, i) for i, j in ((p1, p2), (p2, p1)) for x, y in j)

answered Mar 6, 2013 at 18:18

John La Rooy

306k54 gold badges378 silver badges513 bronze badges

1 Comment

Adel Over a year ago

I wonder if I can use this approach for my problem: stackoverflow.com/questions/68482842/…

Collectives™ on Stack Overflow

combine two loops in python

2 Answers 2

Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related