python pandas – dividing column by another column

python pandas – dividing column by another column

You can use numpy.where:

print df
    hours  $
0       0  8
1       0  9
2       0  9
3       3  6
4       6  4
5       3  7
6       5  5
7      10  1
8       9  3
9       3  6
10      5  4
11      5  7

df[$/hour] = np.where(df[hours] < 1, df[hours], df[$]/df[hours])
print df
    hours  $    $/hour
0       0  8  0.000000
1       0  9  0.000000
2       0  9  0.000000
3       3  6  2.000000
4       6  4  0.666667
5       3  7  2.333333
6       5  5  1.000000
7      10  1  0.100000
8       9  3  0.333333
9       3  6  2.000000
10      5  4  0.800000
11      5  7  1.400000

df[$/hour] = df.apply(lambda x: x[$] if x[$] < 1 else x[$]/x[hours], axis=1)

python pandas – dividing column by another column

You can also filter and select the indexes to set with DataFrame.loc:

df[$/hour].loc[df[hours]>=1] = df[$]/df[hours]
df[$/hour].loc[df[hours]<1] = df[$]