How to separate a Python list into two lists, according to some aspect of the elements

Question

I have a list like this:

[[8, \"Plot\", \"Sunday\"], [1, \"unPlot\", \"Monday\"], [12, \"Plot\", \"Monday\"], [10, \"Plot\", \"Tuesday\"], [4, \"unPlot\", \"         


        

Answer 1

I have a helper function for the general case of partitioning a list in two:

def partition(iterable, condition):
        def partition_element(partitions, element):
            (partitions[0] if condition(element) else partitions[1]).append(element)
            return partitions
        return reduce(partition_element, iterable, ([], []))

For example:

>>> partition([1, 2, 3, 4], lambda d: d % 2 == 0)
([2, 4], [1, 3])

Or in your case:

>>> partition(your_list, lambda i: i[1] == "Plot")