how to find mode of a list that favors the lesser value when 2 values appear equally-CodePudding

def mode(list):
    modelist = max([list.count(x) for x in list])
    return [i for i in list if list.count(i) == modelist][0]

Essentially, the code above works in most cases. However, I want the code to favor the lesser value when there are two equal values. so if the input list was [5,2,2,5] I want it to print 2 instead of printing 5

CodePudding user response：

Is there a reason you don't want to use multimode from the statistics library?

from statistics import multimode

print (min(multimode([2,5,2,5,3,3])))

CodePudding user response：

You can return the min of the list you already have:

def mode(lst):
    modelist = max(lst.count(x) for x in lst)
    return min(i for i in lst if lst.count(i) == modelist)

print(mode([5, 2, 2, 5])) # 2

The code as is now has quite a large time complexity; I guess it is O(n^2). To reduce it, you can set up a counter (e.g., by using collections.Counter):

from collections import Counter

def mode(lst):
    return min(x[1] for x in Counter(lst).most_common(1))

With a long list like [5, 2, 2, 5] * 5000, time spent is like 7.429 vs 0.002 seconds (on my machine).