Subtract two columns in dataframe
Using this as the df:
df = pd.DataFrame([["Australia", 1, 3, 5],
["Bambua", 12, 33, 56],
["Tambua", 14, 34, 58]
], columns=["Country", "Val1", "Val2", "Val10"]
)
You can also do the subtraction and put it into a new column as follows.
>>>df['Val_Diff'] = df['Val10'] - df['Val1']
Country Val1 Val2 Val10 Val_Diff
0 Australia 1 3 5 4
1 Bambua 12 33 56 44
2 Tambua 14 34 58 44
Given the following dataframe:
df = pd.DataFrame([["Australia", 1, 3, 5],
["Bambua", 12, 33, 56],
["Tambua", 14, 34, 58]
], columns=["Country", "Val1", "Val2", "Val10"]
)
It comes down to a simple broadcasting operation:
>>> df["Val1"] - df["Val10"]
0 -4
1 -44
2 -44
dtype: int64
You can do this by using lambda function and assign to new column.
df['Val10-Val1'] = df.apply(lambda x: x['Val10'] - x['Val1'], axis=1)
print df