访问2d python列表中的行以计算值之间的距离

Question

I have a list with a few hundred values which looks like this:

(0.0021265099091875685, 0.0017700721644805513) (0.0026319917728469086, 0.002632415013842871)

I want to calculate the euclidean distance between each row.

The way I plan on calculating it is something like this:

sqrt(0.0021265099091875685 - 0.0026319917728469086)^2 + (0.0017700721644805513 -  0.002632415013842871)^2

I'm having trouble working out how I can access each value in order to do those calculations. If anyone has any ideas about doing this it would be very helpful. Thanks

EDIT: I'm pulling data from a MySQL db. Initially I had two lists, when printed out, a list would look like this:

0.00212650990919 0.00263199177285 0.00332920813651 0.00268428300012 0.00245768768193

I then created a new list by doing this:

someList = zip(list1 , list2)

which gave me the output I have above.

Answer 1

You can use zip:

l1=(0.0021265099091875685, 0.0017700721644805513)
l2=(0.0026319917728469086, 0.002632415013842871)
result=[(x-y)**(1/2) for x,y in zip(l1,l2)]

Answer 2

I am not sure how your data is going to be from your question. I am assuming your data to be as:

data = [
[(0.0021265099091875685, 0.0017700721644805513), (0.0026319917728469086, 0.002632415013842871)],
[(0.0021265099091875685, 0.0017700721644805513), (0.0026319917728469086, 0.002632415013842871)],
[(point-one), (point-two)],
...
]

This will then give you what you need:

[pow(sqrt(item[1][0] - item[0][0]), 2) + pow((item[1][1] -  item[0][1]), 2) for item in data]

Answer 3

Assuming your list looks like this:

lst = [ ((x1,y1),(x2,y2)), ... ]

Then you can just do:

import math
distances = [ math.sqrt((p1[0]-p2[0])**2.0 + (p1[1]-p2[1])**2.0) for p1, p2 in lst ]

Answer 4

Let's say your list looks something like this...

xyz = [(0.0021265099091875685, 0.0017700721644805513), (0.0026319917728469086, 0.002632415013842871), ...]

You can also do...

For item in xyz:
    first_num = item[0]
    second_num = item[1]

Answer 5

Assuming your data looks something like this:

points = [
    (a, b),
    (c, d),
    (e, f),
    ...
]

Then you might do something like this:

d = lambda x, y: ((y[0] - x[0]) ** 2 + (y[1] - x[1]) ** 2) ** 0.5
distances = [d(*pair) for pair in zip(points, points[1:])]