Python map object is not subscriptable

Question

Why does the following script give the error:

payIntList[i] = payIntList[i] + 1000
TypeError: 'map' object is not subscriptable

payList = [] numElements = 0  while True:         payValue = raw_input("Enter the pay amount: ")         numElements = numElements + 1         payList.append(payValue)         choice = raw_input("Do you wish to continue(y/n)?")         if choice == 'n' or choice == 'N':                          break  payIntList = map(int,payList)  for i in range(numElements):          payIntList[i] = payIntList[i] + 1000          print payIntList[i] 

Answer 1

In Python 3, map returns an iterable object of type map, and not a subscriptible list, which would allow you to write map[i]. To force a list result, write

payIntList = list(map(int,payList)) 

However, in many cases, you can write out your code way nicer by not using indices. For example, with list comprehensions:

payIntList = [pi + 1000 for pi in payList] for pi in payIntList:     print(pi) 

Answer 2

map() doesn't return a list, it returns a map object.

You need to call list(map) if you want it to be a list again.

Even better,

from itertools import imap payIntList = list(imap(int, payList)) 

Won't take up a bunch of memory creating an intermediate object, it will just pass the ints out as it creates them.

Also, you can do if choice.lower() == 'n': so you don't have to do it twice.

Python supports +=: you can do payIntList[i] += 1000 and numElements += 1 if you want.

If you really want to be tricky:

from itertools import count for numElements in count(1):     payList.append(raw_input("Enter the pay amount: "))     if raw_input("Do you wish to continue(y/n)?").lower() == 'n':          break 

and / or

for payInt in payIntList:     payInt += 1000     print payInt 

Also, four spaces is the standard indent amount in Python.