Is there a way to round a single column in pandas without affecting the rest of the dataframe?
>>> print(df)
item value1 value2
0 a 1.12 1.3
1 a 1.50 2.5
2 a 0.10 0.0
3 b 3.30 -1.0
4 b 4.80 -1.0
I have tried the following:
>>> df.value1.apply(np.round)
0 1
1 2
2 0
3 3
4 5
5 5
What is the correct way to make data look like this:
item value1 value2
0 a 1 1.3
1 a 2 2.5
2 a 0 0.0
3 b 3 -1.0
4 b 5 -1.0
5 c 5 5.0
You are very close.
You applied the round to the series of values given by df.value1
.
The return type is thus a Series.
You need to assign that series back to the dataframe (or another dataframe with the same Index).
Also, there is a pandas.Series.round
method which is basically a short hand for pandas.Series.apply(np.round)
.
>>> df.value1 = df.value1.round()
>>> print df
item value1 value2
0 a 1 1.3
1 a 2 2.5
2 a 0 0.0
3 b 3 -1.0
4 b 5 -1.0