Delta words between two TXT files - python-3.x

Question

I would like to count the delta words between two files.
file_1.txt has content One file with some text and words..
file_1.txt has content One file with some text and additional words to be found..
diff command on Unix systems gives the following infos. difflib can give a similar output.
$ diff file_1.txt file_2.txt
1c1
< One file with some text and words.
---
> One file with some text and additional words to be found.
Is there an easy way to found the words added or removed between two files, or at least between two lines as git diff --word-diff does.

Answer 1

First of all you need to read your files into strings with open() where 'file_1.txt' is path to your file and 'r' is for "reading mode".
Similar for the second file. And don't forget to close() your files when you're done!
Use split(' ') function to split strings you have just read into lists of words.
file_1 = open('file_1.txt', 'r')
text_1 = file_1.read().split(' ')
file_1.close()
file_2 = open('file_2.txt', 'r')
text_2 = file_2.read().split(' ')
file_2.close()
Next step you need to get difference between text_1 and text_2 list variables (objects).
There are many ways to do it.
1)
You can use Counter class from collections library.
Pass your lists to the class's constructor, then find the difference by subtraction in straight and reverse order, call elements() method to get elements and list() to transform it to the list type.
from collections import Counter
text_count_1 = Counter(text_1)
text_count_2 = Counter(text_2)
difference = list((text_count_1 - text_count_2).elements()) + list((text_count_2 - text_count_1).elements())
Here is the way to calculate the delta words.
from collections import Counter
text_count_1 = Counter(text_1)
text_count_2 = Counter(text_2)
delta = len(list((text_count_2 - text_count_1).elements())) \
- len(list((text_count_1 - text_count_2).elements()))
print(delta)
2)
Use Differ class from difflib library. Pass both lists to compare() method of Differ class and then iterate it with for.
from difflib import Differ
difference = []
for d in Differ().compare(text_1, text_2):
difference.append(d)
Then you can count the delta words like this.
from difflib import Differ
delta = 0
for d in Differ().compare(text_1, text_2):
status = d[0]
if status == "+":
delta += 1
elif status == "-":
delta -= 1
print(delta)
3)
You can write difference method by yourself. For example:
def get_diff (list_1, list_2):
d = []
for item in list_1:
if item not in list_2:
d.append(item)
return d
difference = get_diff(text_1, text_2) + get_diff(text_2, text_1)
I think that there are other ways to do this. But I will limit by three.
Since you get the difference list you can manage the output like whatever you wish.

Answer 2

..and here is yet another way to do this with dict()
#!/usr/bin/python
import sys
def loadfile(filename):
h=dict()
f=open(filename)
for line in f.readlines():
words=line.split(' ')
for word in words:
h[word.strip()]=1
return h
first=loadfile(sys.argv[1])
second=loadfile(sys.argv[2])
print "in both first and second"
for k in first.keys():
if k and k in second.keys():
print k