Column Statistics Min/Max

Problem

Compute basic column statistics for a nullable column.

values may contain None entries. Return [minimum, maximum, null_count]; when every value is None or the column is empty, the minimum and maximum are None.

Return the statistics list.

Hint

Min and max consider only the non-null values.

Test cases

case 1

in: [[3,null,1,7]]

expected: [1,7,1]

case 2

in: [[]]

expected: [null,null,0]

case 3

in: [[null,null]]

expected: [null,null,2]

case 4

in: [[-5,0,-1]]

expected: [-5,0,0]

Starter codePython

def column_stats(values):
    # Your code here
    pass

4 test cases · run your code against them in the editor