The Filter Function

The filter() command is used to remove rows from your data. This can be useful for removing zeros or “no data/NA’s”, or for restricting certain variables in a dataset for an analysis.

This follows the similar syntax as mutate() whereby we specify what dataset we want to filter, followed by how we want to filter.

#The following examples will just keep overwriting the new object "weeds_filtered"

weeds_filtered <- filter(weeds, weeds == "native") 
# Gives us only the rows which are exactly "native" in the weeds column. 

weeds_filtered <- filter(weeds, weeds != "weed") 
# This gives us the same result as their are only two levels of that column. The != means "not equal to"

weeds_filtered <- filter(weeds ,flowers > 20) 
# Flowers greater than 20 m3

So far, we have covered renaming columns, adding new columns and filtering by rows. The next two commands are focused on selecting specific columns and creating new data tables.