Question:
There is an array with a bunch of duplicate elements. I need to display the contents of a specific element of this array and how many of the same elements are in it (output a number).
Array example:
array = ["Bob", "Alex", "Bob", "John"]
(like 2 Bob, etc.)
Answer:
The easiest way to count the number of occurrences of all elements is to use the built-in Counter class from the collections module:
In [4]: from collections import Counter
In [5]: array = ["Bob", "Alex", "Bob", "John"]
In [6]: c = Counter(array)
In [7]: c
Out[7]: Counter({'Bob': 2, 'Alex': 1, 'John': 1})
In [8]: c['Bob']
Out[8]: 2
In [9]: c['Unknown']
Out[9]: 0