If you’ve ever written any Python at all, the chances are you ... iterators can work on the principle of lazy evaluation: as you loop over an iterator, values are generated as required.

A for loop in Python doesn’t require an index ... It takes an iterable and upon each iteration generates a tuple of the index and the object at that index: x = [3,1,4,1,5,9] for index, n ...

How to use “for” loops in Python There are two main types of loop ... Finally, we can actually change the iterator – the number of steps taken on each loop. This will run until n = 10.

Python is a general-purpose programming ... that can store the contents of each file on each iteration.>>>file_in = list() Use a "for" loop to cycle through each file name in the file name list.

In general, for loops are used when you know exactly how many times you plan to run a loop; a while loop is used when the number of iterations is uncertain. Note: The if statement is like a single ...

Here’s how to use Cython to accelerate array iterations in NumPy ... that’s not actually the loop that iterates over your data—should be written in regular Python. Why do this?