Application of map and reduce

This is an example of using map to normalize strings (uppercase letters, the remaining letters lowercase)

#!/usr/bin/env pythondef lower2upper (s):    loop = 0     l =  '     for n in s:         if n.islower ()  and loop == 0:             l = l + n.upper ()              loop += 1        elif  N.isupper ()  and loop == 0:             l = l + n             loop += 1        elif n.islower ()  and  loop != 0:            loop +=  1            l = l + n         else:            l = l  + n.lower ()     return lresult = map (lower2upper, [' Adam ',   ' LISA ',  ' BarT ') print result

This is an example of using reduce to multiply the number in a list

#!/usr/bin/env pythondef prod (list): Def multiply (x, y): return x * y return reduce (multiply, list) print prod ([1, 3, 5, 7])

This is an example of a string-to-int conversion using map and reduce

#!/usr/bin/env pythondef Str2Int (s): DEF fn (x, y): return x * + y def char2num (s): return {' 0 ': 0, ' 1 ': 1, ' 2 ': 2, ' 3 ': 3, ' 4 ': 4, ' 5 ': 5 ', ' 6 ': 6, ' 7 ': 7, ' 8 ': 8, ' 9 ': 9}[s] return reduce (FN, map (Char2num, s)) Print str2int (' 1234 5 ')

Where map is used to split the string into corresponding numbers and return it as a list

Reduce is used to accumulate the sum on each bit.

Reference

[1].http://www.liaoxuefeng.com/wiki/001374738125095c955c1e6d8bb493182103fac9270762a000/ 00141861202544241651579c69d4399a9aa135afef28c44000

Application of map and reduce