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Using an iterator, or using a foreach loop (which internally uses an iterator), guarantees that the most appropriate way of iterating is used, because the iterator knows about how the list is implemented and how best go from one element to the next.
Use the izip() Function to Iterate Over Two Lists in Python It iterates over the lists until the smallest of them gets exhausted. It then zips or maps the elements of both lists together and returns an iterator object. It returns the elements of both lists mapped together according to their index.
Method 1: Add two lists using the Naive Method:A for loop performs the addition of both lists with the same index number and continuously iterates the elements until the end of the list. After that append method, insert the added elements to the third list.
This is as pythonic as you can get:
for lat, long in zip(Latitudes, Longitudes):
print(lat, long)
Another way to do this would be to by using map.
>>> a
[1, 2, 3]
>>> b
[4, 5, 6]
>>> for i,j in map(None,a,b):
... print i,j
...
1 4
2 5
3 6
One difference in using map compared to zip is, with zip the length of new list is
same as the length of shortest list.
For example:
>>> a
[1, 2, 3, 9]
>>> b
[4, 5, 6]
>>> for i,j in zip(a,b):
... print i,j
...
1 4
2 5
3 6
Using map on same data:
>>> for i,j in map(None,a,b):
... print i,j
...
1 4
2 5
3 6
9 None
Good to see lots of love for zip in the answers here.
However it should be noted that if you are using a python version before 3.0, the itertools module in the standard library contains an izip function which returns an iterable, which is more appropriate in this case (especially if your list of latt/longs is quite long).
In python 3 and later zip behaves like izip.
in case your Latitude and Longitude lists are large and lazily loaded:
from itertools import izip
for lat, lon in izip(latitudes, longitudes):
process(lat, lon)
or if you want to avoid the for-loop
from itertools import izip, imap
out = imap(process, izip(latitudes, longitudes))
for Lat,Long in zip(Latitudes, Longitudes):
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