Find Median Given Frequency of Numbers — LeetCode 571 Python Solution

Table: Numbers +-------------+------+ | Column Name | Type | +-------------+------+ | num | int | | frequency | int | +-------------+------+ num is the primary key (column with unique values) for this table. Each row of this table shows the frequency of a number in the database.

+-------------+------+
| Column Name | Type |
+-------------+------+
| num         | int  |
| frequency   | int  |
+-------------+------+
num is the primary key (column with unique values) for this table.
Each row of this table shows the frequency of a number in the database.

import pandas as pd

def median_from_frequencies(numbers: pd.DataFrame) -> pd.DataFrame:
    df = numbers.sort_values('num')
    df['cum'] = df['frequency'].cumsum()
    total = int(df['frequency'].sum())
    if total == 0:
        return pd.DataFrame({'median': []})
    if total % 2 == 1:
        pos = (total + 1) // 2
        median = df.loc[df['cum'] >= pos, 'num'].iloc[0]
    else:
        pos1 = total // 2
        pos2 = pos1 + 1
        m1 = df.loc[df['cum'] >= pos1, 'num'].iloc[0]
        m2 = df.loc[df['cum'] >= pos2, 'num'].iloc[0]
        median = (m1 + m2) / 2
    return pd.DataFrame({'median': [float(median)]})