I'm trying to map the following function over a pandas dataframe (basically a list) in python 2.7:
df["Cherbourg"] = df["Embarked"].map(lambda x: if (x == "C") 1 else 0)
But python errors saying using a lambda function like this is a syntax error. Is there some way to map an if statement like this in python?
Try
lambda x: 1 if x == "C" else 0
possible duplicate of Is there a way to perform "if" in python's lambda
Example :
map(lambda x: True if x % 2 == 0 else False, range(1, 11))
result will be - [False, True, False, True, False, True, False, True, False, True]
It will be simpler to just do this:
df["Cherbourg"] = (df["Embarked"] == "C").astype('int)
df["Cherbourg"] = df["Embarked"].apply(lambda x:1 if x == 'C' else 0)
A more readable approach:
def mapping(row):
if row.Embarked == 'C':
row.Cherbourg = 1
else:
row.Cherbourg = 0
return row
df.apply(mapping, axis='columns')
