Learning Pandas

Boolean selection

Items in a Series can be selected, based on the value instead of index labels, via the utilization of a Boolean selection. A Boolean selection applies a logical expression to the values of the Series and returns a new Series of Boolean values representing the result for each value. The following code demonstrates identifying items in a Series where the values are greater than 5:

In [58]:
   # which rows have values that are > 5?
   s = pd.Series(np.arange(0, 10))
   s > 5

Out[58]:
   0    False
   1    False
   2    False
   3    False
   4    False
   5    False
   6     True
   7     True
   8     True
   9     True
   dtype: bool

To obtain the rows in the Series where the logical expression is True, simply pass the result of the Boolean expression to the [] operator of the Series. The ...