user3084006 - 10 months ago 50

Python Question

Are there single functions in pandas to perform the equivalents of SUMIF, which sums over a specific condition and COUNTIF, which counts values of specific conditions from Excel?

I know that there are many multiple step functions that can be used for

for example for

`sumif`

`(df.map(lambda x: condition), or df.size())`

`.sum()`

and for

`countif`

`(groupby functions`

`.count())`

Is there simple one step process to do these functions where you enter the condition and the data frame and you get the sum or counted results?

Answer

You can first make a conditional selection, and sum up the results of the selection using the `sum`

function.

```
>> df = pd.DataFrame({'a': [1, 2, 3]})
>> df[df.a > 1].sum()
a 5
dtype: int64
```

Having more than one condition:

```
>> df[(df.a > 1) & (df.a < 3)].sum()
a 2
dtype: int64
```

Source (Stackoverflow)