How to iterate through a list of coordinates and calculate distance between them?

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Within a list, there are coordinates with x and y values.

[(7, 9), (3, 3), (6, 0), (7, 9)]

I can calculate the distance between two points.

distance_formula = math.sqrt(((x[j]-x[i])**2)+((y[j]-y[i])**2))

I am having a hard time going through the list and calculating the distance between each point. I want to calculate the distance between the first index and second index, second index and third index, third index and forth index...

coordinates distance iterator list python
3 Answers

You can do that with zip(). zip() will make pairs of coordinates and let you iterate through them conveniently.

coordinates = [(7, 9), (3, 3), (6, 0), (7, 9)]

for (x1, y1), (x2, y2) in zip(coordinates, coordinates[1:]):
    distance_formula = math.sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2)
    print(distance_formula)
user_63381790

With a List Comprehensions

import math

xy = [(7, 9), (3, 3), (6, 0), (7, 9)]

distances = [math.sqrt(((xy[i+1][0]-xy[i][0])**2)+((xy[i+1][1]-xy[i][1])**2)) for i in range(len(xy)-1)]

print(distances)

>>> [7.211102550927978, 4.242640687119285, 9.055385138137417]
user_77588040

As I understood you want to find the distances between point 0 and point 1, point 1, and point 2...

if so here is your answer

i = 0
n = [(7, 9), (3, 3), (6, 0), (7, 9)]
result = []

for item in range(len(n)-1):
   distX = abs(n[i][0] - n[i+1][0])
   distY = abs(n[i][1] - n[i+1][1])

   hypotenuse = math.sqrt((distX*distX) + (distY*distY)) 
   result.append(hypotenuse)

   i =i + 1
user_132525430
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