Demo of how to find the order of several entries in a row of numerical data.

find_rank.py

#!/usr/bin/env python

"""
Demo of how to find the order of several entries in a row of numerical data.
"""

import numpy as np
import pandas

df = pandas.DataFrame(np.random.rand(5, 3), columns=['a', 'b', 'c'])

def find_rank(x):
    """
    Return ordering of given list.
    """

    N = len(x)
    x_sorted = sorted(x)
    result = []
    for i in xrange(N):
        result.append(x_sorted.index(x[i]))
    return result

def find_rank_rev(x):
    """
    Return reverse ordering of given list.
    """

    N = len(x)
    x_sorted = sorted(x, reverse=True)
    result = []
    for i in xrange(N):
        result.append(x_sorted.index(x[i]))
    return result

# Find ordering of each row:
df_rank = df.apply(find_rank, 1)
df_rank_rev = df.apply(find_rank_rev, 1)