How to compare two lists in Python and count ALL matches?

Question

I have two lists of strings. I want to compare all the items in list 1 to list 2 and then count the matches. Here's what I've tried:

count = 0

global_fruit = ['apples', 'bananas', 'pears', 'oranges', 'peaches', 'apricots', 'mangoes']
local_fruit = ['bananas', 'apricots', 'oranges']

if any(f in global_fruit for f in local_fruit):
count += 1

print(count)

This returns a count of 1 because the script exits as soon as it finds the first match in the second list. I want it to return a count of 3 because there are three matches between the lists.

Is there a way to do this? Order is not important.

https://stackoverflow.com/a/13323960/10634638 – estinamir May 27 '20 at 14:08 — estinamir, May 27 '20 at 14:08
len(set(global_fruit) & set(local_fruit)) – Alkesh Mahajan May 27 '20 at 14:58 — Alkesh Mahajan, May 27 '20 at 14:58

Pavel Botsman · Accepted Answer · 2021-11-30T07:22:21.747

4

You can use sum instead of any and get the result immediately:

global_fruit = ['apples', 'bananas', 'pears', 'oranges', 'peaches', 'apricots', 'mangoes']
local_fruit = ['bananas', 'apricots', 'oranges']

count = sum(f in global_fruit for f in local_fruit)

print(count)

Also, you could convert your lists into sets and find the number of intersections:

global_fruit = ['apples', 'bananas', 'pears', 'oranges', 'peaches', 'apricots', 'mangoes']
global_fruit_set = set(global_fruit)
local_fruit = ['bananas', 'apricots', 'oranges']
local_fruit_set = set(local_fruit)

count = len(global_fruit_set.intersection(local_fruit_set))
print(count)

edited Nov 30 '21 at 07:22

answered May 27 '20 at 14:06

Pavel Botsman

773
1
11
25

Both your answers worked, but the first one was ideal for what I needed. Thanks to you and also the answer from komatiraju032. My account is quite new so you won't see the upvotes but they are there. – ipconfuse May 27 '20 at 14:21

score 3 · Answer 2 · answered May 27 '20 at 14:11

3

global_fruit = ['apples', 'bananas', 'pears', 'oranges', 'peaches', 'apricots', 'mangoes']
local_fruit = ['bananas', 'apricots', 'oranges']
count=0 
for a in global_fruit:
    if(a in local_fruit):
        count+=1
print(count)

answered May 27 '20 at 14:11

Venkata Chaitanya Yadla

41
3

2

Welcome to Stack Overflow. Code dumps without any explanation are rarely helpful. Stack Overflow is about learning, not providing snippets to blindly copy and paste. Please [edit] your question and explain how it works better than what the OP provided. See [answer]. – ChrisGPT was on strike May 28 '20 at 01:10

score 2 · Answer 3 · answered May 27 '20 at 14:08

2

Try this:

global_fruit = ['apples', 'bananas', 'pears', 'oranges', 'peaches', 'apricots', 'mangoes']
local_fruit = ['bananas', 'apricots', 'oranges']

print(len(local_fruit) - len(set(local_fruit) - set(global_fruit)))

answered May 27 '20 at 14:08

deadshot

8,881
4
20
39

How to compare two lists in Python and count ALL matches?

3 Answers3