How to get the amount of 'strings'(?) and print

Question

I have a list of different words divided with ':' in a .txt, as such:

banana:pinapple
apple:grapes
orange:nuts
...

How can I get the number of lines that have a word on the left of the semicolon and print that number?

I am using this to seperate them:

string1, string2 = line.split(':')

I want to print the number sort of like this:

print(number of lines where there exists is a string1)

Naive way - after splitting combine them as a single list and use Counter — Aditya, May 14 '17 at 15:27
@aryamccarthy I wanted to print the amount so I've tried print(len(string1)) but I don't really know what to search for. — Jesper, May 14 '17 at 15:28
Other way which is a bit easy will be use a dict with default key implemented — Aditya, May 14 '17 at 15:28
@ADITYA it's not clear whether the intent is to count each string or simply get the number of lines which are not empty to the left of the colon. — Arya McCarthy, May 14 '17 at 15:29
@aryamccarthy I just want to get the number of lines which are not empty to the left — Jesper, May 14 '17 at 15:30
The example you have given us doesn't make sense given your question about counting the amount of words on the left. If it's a list containing only strings where two words have `:` between them, you can just get the length of your list to get the number of the words on the left since it's the same as the number on the right and the same as the number of strings in your list. Please provide more information and/or edit your question/example. — rbaleksandar, May 14 '17 at 15:30
@Jesper Has your question been sufficiently addressed? If not, what's unclear? If so, you should mark the checkbox beside the correct answer. — Arya McCarthy, May 15 '17 at 00:22

Arya McCarthy · Answer 1 · 2017-05-14T15:36:38.023

0

count = 0
for line in f:
    string1, string2 = line.split(':')
    if string1:
        count += 1
print(count)

Your question asks about the number of words on the left, which is exactly what this counts. This handles the case where the line is :foo. Still, you haven't suggested that there are ever lines without a colon or lines with more than one. Additionally, you haven't said there will be more than one word on the left. I choose to ignore these cases since you haven't indicated their existence.

edited May 14 '17 at 15:36

answered May 14 '17 at 15:31

Arya McCarthy

8,554
4
34
56

Basically just counting the no of lines in a text file will also do? – Aditya May 14 '17 at 15:32
This handles the case where the line is `:foo`. – Arya McCarthy May 14 '17 at 15:32
@aryamccarthy Is this a valid case though? The OP's example doesn't show any indication that `:foo` or `foo:`, `:` is present. – rbaleksandar May 14 '17 at 15:33
The question is focused on the left, so I'm being cautiously general. – Arya McCarthy May 14 '17 at 15:34
@rbaleksandar Yep that's true...but be prepared for every possibility or else face the Traceback... – Aditya May 14 '17 at 15:34

score 0 · Answer 2 · answered May 14 '17 at 15:39

fileName = 'myfile.txt'

counterDict = {}

with open(fileName,'r') as fh:
  for line in fh:
    left,right = line.rstrip('\n').split(':')
    counterDict[left] = counterDict.get(left,0)+1  

print(counterDict)

# cat myfile.txt

banana:pinapple
apple:grapes
orange:nuts
banana:pinapple
apple:grapes
orange:nuts
banana:pinapple
apple:grapes
orange:nuts

# Result

{'banana':3,'apple':3,'orange':3}

score 0 · Answer 3 · answered May 14 '17 at 15:46

So I'm not sure I understand your question based on all the answers provided. All you want to know is how to count the number of lines in a text file?

Yes I see you said "That have a word on the left of the colon", but why would you have a colon on a line with out any other text? Your saying that your program writes the text in such a way that it's "example":"example" right?

If that's the case you wouldn't have a colon on a line with out any other text, unless you intentionally input nothing which is still something.

def get_total_lines(self, path):
    counter = 0
    try:
        if os.path.isfile(path):
            with open(path, 'r') as inFile:
                for i in enumerate(inFile):
                    counter = counter + 1
                    return str(counter)
        elif not os.path.isfile(path):
            print("Error: The file you're attempting to read does not exist, aborting reading process...")
    except IOError as exception:
        raise IOError('%s: %s' % (path, exception.strerror))
        return None

That's got some basic form of error checking, here is one with out it.

def get_total_lines(self, path):
    counter = 0
    with open(path, 'r') as inFile:
        for i in enumerate(inFile):
            counter = counter + 1
            return str(counter) # could be int or w/e else you want it to be

That will count the lines, if you want to strip off a word or the colon it can be easily adapted to do that.

Jesper · Accepted Answer · 2017-05-15T15:43:22.373

-1

Just got the number of lines instead like this:

with open(listname) as list:
    lines = len(list.readlines())

edited May 15 '17 at 15:43

answered May 15 '17 at 06:28

Jesper

5
4

You should be clearer in the future about your problem constraints. The 'left-hand side' was irrelevant. – Arya McCarthy May 16 '17 at 04:33
@aryamccarthy Yeah, sorry about that, thanks for attempting to help though! – Jesper May 16 '17 at 16:28

How to get the amount of 'strings'(?) and print

4 Answers4