在 Python 中对坐标进行排序

Question

I have a list of coordinates like:

[44.64,-123.11;38.91,-121.99;40.35,-122.28;43.21,-123.36;41.77,-122.58;37.77,-122.42]

I need to sort this list. Any suggestions ?

EDIT: Sorry for not sharing the expected output:

It should be [44.64,-123.11;43.21,-123.36;41.77,-122.58;40.35,-122.28;38.91,-121.99;37.77,-122.42]

Answer 1

li = [44.64,-123.11;38.91,-121.99;40.35,-122.28;43.21,-123.36;41.77,-122.58;37.77,-122.42]

Your "list" looks more like a string , with ";" and "," to separate 2D points and their values. I imagine that you want a list of tuples, that represent the x and y coordinates? So first you need to split your string into a list

li = li.split(';')

Now you have a list of string s, that you need to split into pairs of float values. You can do that with two list comprehensions

li = [(float(a.split(',')[0]), float(a.split(',')[1])) for a in li]

Now you have a list of coordinates that you could sort in some way. Maybe smallest x first or something. Use Python's sorted build-in function to do that, eg

sorted_li = sorted(li, key=lambda x: x[0])

The docs are here, read them.

https://docs.python.org/3.6/library/functions.html#sorted