For example, right here if I have this URL string and adds some space to it and come down to print it out I could say URL and then simply say strip and then because it's a function call it with parens. Now if I hit enter here this is going to return back the URL

Notice how even though I added these spaces before and after strip got rid of them and that is the standard behavior with strip.

However, in this guide I wanna give you a more advanced look into how you can leverage strip and some of the functions that are similar to it. So I started with this example of a URL because this is a pretty common reason why you would use strip and a few of the functions that are similar to it

Let's say that we want to be able to take off this https:// Say we just wanted to print out Google and we knew that we were going to have https:// right here in front of each one of the URL strings. What I can do is I can say URL strip and then pass in as a string this https:// and now if I run this you're gonna see that it prints out Google.

Now there is if you're following along on repl.it then you'll see there is a little error here

It's not technically an error it's a warning but it says suspicious argument in string strip call and that is because you really do need to know when you're calling this type of function you want to make sure that you're not allowing your users to perform these types of strip calls because what would happen is you could potentially have someone inject something that would conflict with other data components or cause an issue. So from a security perspective Python is saying be careful here but in our case, we know that we are the ones that are providing the data so it's fine for us right here.

That is one option, now this is great but we can actually get even more specific than this so say that we want it to convert our string and actually have it so it printed out just the word I'll do it as a comment in Python. Just the word google just like this Google in uppercase like a title like a company name and then without the .com without https:// without all of that.

Well, we can do that and we're going to get a little bit more advanced so I'm going to keep what we have here and the next thing I'm going to do is use a sister method to strip which is going to be lstrip(Lstrip) and so 'lstrip' is short for left strip. So this is going to do is it's more specific. It's only going to look at the strings value from the left all the way to where it finds its match. I'm going to comment this right here and so now if I print out url.lstrip and print that you can see it gives us the exact same behavior.

Now if you guessed that 'lstrip' might have a cousin. Then you would be right and it is rstrip and let's create a new string and were going to perform reassignment here so I'm gonna say 'lstrip'. Let's pull out the https:// let's remove that and let's reassign it to URL and we're going to do the same thing here. But now I'm going to pull out the .com and so here I say rstrip which stands for right strip. So this is going to go to our string. It's going to start at the very end and it's going to move to the left so in this case, it's going to try to find .com and then we are reassigning that URL and just to make everything look nice. I'm going to say URL and said this equal to url.capitalize. And that is a function so we'll end it with parens. And now we can simply pass in URL to our print statement and see if this works. So if I run this you can see that it does.

It prints out Google and it looks more like the company name even though we started with simply grabbing the url. So there's is something very handy.

I use r and 'lstrip' quite a bit especially in machine learning algorithm data cleanup because there is going to be so many times where you'll get data and one of the first things you need to do with that is to make sure that it is formatted properly because if you get data from some source that had some kind of weird formatting such as starting a sentence off with the comma or something like that which you will get that it may sound weird you will get that kind of data quite a bit in machine learning because you're dealing with raw data. So you're getting data that may have just been scraped from millions of websites or something like that and you need to make sure that you have all of the data formatted properly so your algorithm can actually run across the data. And so 'lstrip' in 'rstrip' are ways that you can do that. So you can quickly go through pull off any data you know is going to be there check to see if it's there and pull it out if you don't want it. and so that is a very helpful tool. One if your web application or mobile developers but also if you're in machine learning.

Code

url = 'https://google.com'

print(url.strip('https://'))

url = url.lstrip('https://')
url = url.rstrip('.com')

print(url.capitalize())