How to get rid of Divide by Zero error in python pandas?

Question

I have a dataframe that has two columns:

df

There are some scientific values like 0E-10, I want create a new column such that:

df["new_col"]=df["fruits_ratio"]/(df["fruits_ratio"]+df["vegetables_ratio"])

But it give me an error like this: DivisionByZero: [<class 'decimal.DivisionByZero'>]

Is there a way to either replace the 0-E10 values or how can I avoid the error?

Thanks

Possible duplicate of [How to deal with "divide by zero" with pandas dataframes when manipulating columns?](https://stackoverflow.com/questions/38886512/how-to-deal-with-divide-by-zero-with-pandas-dataframes-when-manipulating-colum) — Ankur Sinha, Jul 26 '19 at 15:47

score 2 · Accepted Answer · answered Jul 26 '19 at 15:51

2

I think the float function will fix this for you float(). Assign the entire column as floats since most are already.

answered Jul 26 '19 at 15:51

Chris Macaluso

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Float will handle dividing by zero? – zack-overflow Jul 26 '19 at 15:53
Yes, well.. floats will produce `float('inf')` when dividing by zero in the context of a pandas series or dataframe division along an axis. – Zev Isert Nov 04 '20 at 22:20

Steven Rumbalski · Answer 2 · 2019-07-26T16:27:30.447

Given:

df = pd.DataFrame({'a':[0,1,2,3,0,1,2,3], 'b':[0,1,0,1,1,0,1,0]})

as

Create a mask to identify where a or b is not zero which are safe to calculate on.

mask = (df['a'] != 0) | (df['b'] != 0)

the mask

0    False
1     True
2     True
3     True
4     True
5     True
6     True
7     True

Fill the result column with NaN then overwrite the ones you can calculate:

df['c'] = pd.np.NaN
df.loc[mask, 'c'] = df['a'] / (df['a'] + df['b'])

result

   a  b         c
0  0  0       NaN
1  1  1  0.500000
2  2  0  1.000000
3  3  1  0.750000
4  0  1  0.000000
5  1  0  1.000000
6  2  1  0.666667
7  3  0  1.000000

Applied to your question:

mask = (df['fruits_ratio'] != 0) | (df['vegetables_ratio'] != 0)
df['new_col'] = pd.np.NaN
df.loc[mask, 'new_col'] = df['fruits_ratio'] / (df['fruits_ratio'] + df['vegetables_ratio'])

score 0 · Answer 3 · answered Jul 12 '22 at 15:10

0

Note that pandas supports division by zero for columns with numeric dtype (such as float and int64) by returning a result of inf. However, for columns of object type, it raises a ZeroDivisionError exception.

See this question and answer for examples.

answered Jul 12 '22 at 15:10

constantstranger

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How to get rid of Divide by Zero error in python pandas?

3 Answers3