map() function getting input

Question

I'be trying to get an special input from the user and then save it in something like a dictionary. The input I have in mind is something like:

>>> id 1230

and I want it to be save in the form of:

{"id":1230}

or

[(id,1230)]

my problem is that there are actually two variables,one is a string and another is an integer,so somehow I have the get a line from the user,then the first and second parts should be separated and saved in one of the forms I mentioned. I know it has to do with the map() function and maybe a lambda expression is also used.once I used such a code to get two integers:

x,y = map(int,input().split())

but I really don't know how to do it with a string and integer. Thank you very much

Solution 1

The question about whether you would like to store the data as a dict or a list of tuples depends on whether you want the user to overwrite existing values or not. If you store the values in a dict, the input of

id 1230
hi 16
id 99

will produce a dictionary like {"id": 99, "hi":16} because the second input id overwrites the first. A list of tuples approach would produce [("id", 1230), ("hi", 16), ("id", 90)].

How to parse the values has already been suggested by other people, but for completion I will add it to my answer as well.

Dict approach

d = dict()
var = input('Enter input: ')
key, value = var.split()
d[key] = int(value)

List approach

L = list()
var = input('Enter input: ')
key, value = var.split()
L.append((key, int(value)))

Solution 2

You do not need map here. You can use str.split to split by whitespace and then create a dictionary explicitly:

var = input('Enter input: ')  # 'id 1230'
key, value = var.split()
d = {key: int(value)}         # {'id': 1230}

You can add some checks to ensure the format is input correctly before proceeding with creating the dictionary:

while True:
    try:
        var = input('Enter input: ')  # 'id 1230'
        key, value = var.split()
        d = {key: int(value)}         # {'id': 1230}
        break
    except ValueError:
        print('Incorrect format supplied, type "id 1230" expected. Please try again.')

Solution 3

You need to split the input and save it to a dictionary.

data = dict()
keyValue = input()
data[keyValue.split(' ')[0]) = keyValue.split(' ')[1]

Solution 4

usr_inpt = input("enter whatever you want to enter: ")
id, value = usr_inpt.split()
output = [(id,value)]

this formats your input into a tuple ...but I would not recommend dictionary, since every key must be unique and if you have multiple entries from the user, you could end up overwriting previously inputted user inputs.

Solution 5

>>> i = "id"
>>> x = 1234
>>> out = {i:x}
>>> out
{'id': 1234}
>>> out = [(i,x)]
>>> out
[('id', 1234)]
>>> 
>>>
>>> 
>>> ix = input("--> ")

--> id 1234
>>> ix = ix.split()
>>> out = {ix[0]:int(ix[1])}    
>>> out
{'id': 1234}
>>> out = [(ix[0],int(ix[1]))]    
>>> out
[('id', 1234)]
>>> 

Or maybe a function will work:

>>> add = lambda x:{x.split()[0],int(x.split()[1])}
>>> out = add(input("--> "))
--> id 1234
>>> out
{1234, 'id'}
>>> 

View more solutions

Comments

[chepner]

Note that this ignores whatever handling you need to provide in case the user doesn't provide the expected input.

[chepner]

input always returns a str; you don't need to call str yourself.

[FrastoFresto]

@jpp thank you very much,but I was curious to know can the code you wrote be compressed in a map()?

[chepner]

@FarzinNasiri No! map applies the same function to every element in an iterable; you don't want to do that.

[Cut7er]

thanks for the clarification - mostly I do int(input()) for numbers, didnt occured to me that it is not needed for string input :-)

[Thijs van Ede]

@schwobaseggl you're completely right, I edited it in my answer

[jpp]

@FarzinNasiri, I've also added some error-handling to ensure the correct format is supplied.

[SethMMorton]

split() should be preferred over split(‘ ‘) since it with split on an arbitrary number of white space characters, as well as handle tabs.