Python List-generated

Reprint to: http://blog.csdn.net/watermusicyes/article/details/43762551

In Python, list generation is an expression that makes it easy to build lists. Sometimes it can replace list.append ().

What if you want to build [1*1, 2*2, 3*3, ..., 10*10]? You can use loops:

>>> l= []>>> for x in range (1, ten): ...     L.append (x*x) ... >>> l[1, 4, 9, 16, 25, 36, 49, 64, 81]

and list generation, you can use a sentence instead of the tedious loop above to complete the above operation:

List-Generated writing format: [x*x for X in range (1, 11)]

First: Put the elements you want to create x*x to the front

Second: Follow the For loop

This allows the list to be created.

The For loop can also be followed by an if judgment, so that even squares can be filtered out:

Of course, you can use a two-layer loop to generate a full array:

How to use two variables to generate a list:

D = {' Java ': "}l", ' C ': "", "" The "," C + + ":" The "" The "" The "" +v "=" k + ' = ' "for K, V in D.iteritems ()]print L

　　

　

　　

Python List-generated