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# Column And Row Sums In Pandas And Numpy

I feel like I am constantly looking it up, so now it is documented:

If you want to do a row sum in pandas, given the dataframe df:

```
df.sum(axis=1)
```

and a column sum:

```
df.sum(axis=0)
```

If you want to do a row sum in numpy[1], given the matrix X:

```
import numpy as np
np.sum(X,axis=1)
```

and column sums:

```
import numpy as np
np.sum(X,axis=0)
```

[1] http://docs.scipy.org/doc/numpy/reference/generated/numpy.sum.html