Map and reduce for Python

Map (f, Itera) # Use F (x) for each element

lambda x:x**2>>> l = map (sq,[-1,0,1,2,-3])>>> list (l) [1, 0, 1, 4, 9]

Of course, you can also pass in two parameters:

Lambda x, y:x + y>>> l = map (lambda x, y:x + y, [1, 3, 5, 7, 9], [2, 4, 6, 8, ten  ])>>> list (l) [3, 7, 11, 15, 19]

Reduce (f (x), Itera) # x1 The result F (x1) Continuation and the next element of the sequence x2 do the cumulative calculation for the previous

function F must have two parameters x, y

 from Import Reduce def # define an Add function        return x+y>>> reduce (add,[1,2,3,4,6])16

Add (x, y) is a function that we define, which passes the Add function and the [1,2,3,4,6] list to the reduce function, which is equivalent to 1+2+3+4+6 = 16. That is, the result continues and the next element of the sequence is accumulated.

Map and reduce for Python