python - How do I compare one index to the previous index within the same list? -


i'm trying make program @ each previous number in list, , determine if number bigger it. if is, should record how many times bigger, , return @ end. i.e. count (i'm using num variable) starts @ 0. 10 bigger 7 num becomes 1. 7 isn't bigger 20 count stays same. 20 bigger 15 count (num) 2. , 15 bigger 4 (count 3). 4 not bigger 6 (count not change) , 6 not bigger next number because there no next number. have now. i'm thinking lst[i] , lst[i+1] need used reference index maybe? can walk me through this? thanks.

def count(lst): num = 0 sort of division here? add num variable? #main prog ( count([10, 7, 20, 15, 4, 6]) ) 

import numpy np def count(lst): return sum(np.diff(lst)>0)

diff gives difference between successive elements, sum returns number of positive differences.


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