Both the .iloc and .loc indexers are capable of selecting a single element, a scalar value, from a Series or DataFrame. However, there exist the indexers, .iat and .at, which respectively achieve the same thing at faster speeds. Like .iloc, the .iat indexer uses integer location to make its selection and must be passed two integers separated by a comma. Similar to .loc, the .at index uses labels to make its selection and must be passed an index and column label separated by a comma.
Speeding up scalar selection
Getting ready
This recipe is valuable if computational time is of utmost importance. It shows the performance improvement of .iat and .at over .iloc and .loc when using scalar selection.