For instance, how would I define a function so that every odd integer in a list is replaced with the string 'odd'? Thanks
list = [10 , 11, 12, 13, 14, 15, 16,]
Intended result
[10, 'odd', 12, 'odd', 14, 'odd', 16]
5 Answers
A one line solution can be:
print [(i,'odd')[i%2] for i in list]
I feel like you should probably get the solution on your own, but anyway...
result = []
for i in list:
if i % 2 != 0:
result.append('odd')
else:
result.append(i)
Or, maybe something to push you forward:
def turn_odd(i):
if i % 2 != 0:
return 'odd'
else:
return i
list = [10 , 11, 12, 13, 14, 15, 16,]
result = map(lambda x: turn_odd(x), list)
Comments
for i in range(len (list)):
if (list[i] % 2 != 0):
list[i] = "odd"
4 Comments
Tom Karzes
A first argument of 0 to
range may be omitted. I.e., one would normally just write range(len(list)).
Jeremy Hanlon
Okay. I haven't used python in a while. I'll change it now
dawg
It is better to do
for i, x in enumerate(list): if x%2: list[i]='odd'dawg
@Reti43 It is not the parity of the index to check -- it is the parity of the object inside. So your code is wrong...
You can use list comprehension:
list = [10 , 11, 12, 13, 14, 15, 16]
new_list = [i if i % 2 == 0 else "odd" for i in list]
Here's a good example of how it works: if/else in Python's list comprehension?
2 Comments
Tom Karzes
Technically this isn't what OP asked for. OP asked to replace the odd elements of a list, not generate a new list with the odd elements replaced. Whether this matters to OP or not is unclear, but it does create a new list.
zondo
You could do
list[:] = ... instead of new_list = ... You shouldn't be using list as a variable name anyway because it shadows the built-in type. You could also do ["odd" if i % 2 else i for i in list]First note that list is reserved for the type list in Python, so I will use my_list instead. Then you have three options:
A loop with a conditional
for i in range(0, len(my_list)):
if (i % 2 != 0):
my_list[i] = "odd"
List comprehension (same logic as above)
my_list = ["odd" if i % 2 != 0 else my_list[i] for i in range(len(my_list))]
A loop without a conditional
for i in range(1, len(my_list), 2):
my_list[i] = "odd"
listthen masks the built-in functionlist(iterator)