Generate a binary values dictionary by searching in two lists-CodePudding

I have two lists

list1=['ABC','DBA','CBA','RBA','DCA','RMA']
list2=['ABC,'DBA','RMA']

Expected Output

{'ABC':1,'DBA':1,'CBA':0,'RBA':0,'DCA':0,'RMA':1}

if the values of list1 are present in list2 then the values of output dictionary would be 1, otherwise 0.

CodePudding user response：

If the size of list2 is small, you can use a simple dictionary comprehension:

{key: int(key in list2) for key in list1}

However, if list2 is long, you should turn it into a set for faster lookups:

lookup_set = set(list2)
{key: int(key in lookup_set) for key in list1}

Both of these output:

{'ABC': 1, 'DBA': 1, 'CBA': 0, 'RBA': 0, 'DCA': 0, 'RMA': 1}

CodePudding user response：

list1=['ABC','DBA','CBA','RBA','DCA','RMA']
list2=['ABC','DBA','RMA']

output = {}
for x in list1:
    output[x] = 0

for x in list2:
    if (x in output):
        output[x] = 1
    else:
        output[x] = 0

print(output) # {'ABC': 1, 'DBA': 1, 'CBA': 0, 'RBA': 0, 'DCA': 0, 'RMA': 1}

CodePudding user response：

If list1 will always contain all possible keys

{s:int(s in list2) for s in list1}

But in the general case, where there could be distinct keys in either, this will work

{s:int(s in list2 and s in list1) for s in list1 list2}

Note: Because python can automatically interpret booleans as integers then the only reason to cast to int is if you need to print the dictionary. Otherwise I would just leave the values as True/False