Question

I am really new to python and I have two csv file. The first one (more.csv) has content of

A123,B456,C789

The second one (less.csv) has content of

B456

I want so that when they are the same they store the similar item into a variable called “same”

I figure it would start with something like:

more = open('more.csv','r')
less= open('less.csv','r')
for item in unitid:

Thank you.

Answer 1

If they’re only one line, you can use the set object (a python built-in) to compare them, for instance:

>>> a = ['A123','B456','C789','D007']
>>> b = ['B456','D007','E009']
>>> c = list(set(a).intersection(b))
>>> print c
['B456', 'D007']

The full method to compare from files would look like:

def compare( fileA, fileB ):
    a_file = open(fileA, 'r')
    a_data = a_file.read()
    a_file.close()

    b_file = open(fileB, 'r')
    b_data = b_file.read()
    b_file.close()

    # compare the contents
    a_set = set(a_data.split(','))
    b_set = set(b_data.split(','))

    return list(a_set.intersection(b_set))

compare('more.csv', 'less.csv')

If they are more than a single line per file, then you’d still be able to use this, you’d just have to modify it a bit – I guess storing the intersections into an array that represents the line-by-line similarities or something.