Question

I have a list with two elements like this:

list_a = [27.666521, 85.437447]

and another list like this:

big_list = [[27.666519, 85.437477], [27.666460, 85.437622], ...]

And I want to find the closest match of list_a within list_b.

For example, here the closest match would be [27.666519, 85.437477].

How would I be able to achieve this?

I found a similar problem here for finding the closest match of a string in an array but was unable to reproduce it similarly for the above mentioned problem.

P.S.The elements in the list are the co-ordinates of points on the earth.

Answer 1

From your question, it’s hard to tell how you want to measure the distance, so I simply assume you mean Euclidean distance.

You can use the key parameter to min():

from functools import partial

def distance_squared(x, y):
    return (x[0] - y[0])**2 + (x[1] - y[1])**2

print min(big_list, key=partial(distance_squared, list_a))