Welcome to Python programming we have just started about the if condition so today I'll be starting with the functions Let us introduce to you all the Python functions and we'll again get back to the if conditions in our next videos. So start with the Python functions. So what is a Python function a function is a block of code which only runs when it is called you can pass data known as parameters into a function a function can return data as a result. So there are various functions in Python few are string function for your numeric function, I'll explain you on the both the both the functions. So let's start with the string function. So first here and write a phrase.

So just even name the variable name and providing phrase. So in this phrase, high writer string I write in this way. Suppose I'm right on in capital submitted in an application. So I'm right. By can is cool. So I'm writing this.

Now, the next step what I will do is suppose I want to convert this first do one thing for sprint is then see what happens. So it's printing in capital letter all in capital Python is cool. Now I want to change this uppercase string to a lowercase so what is the function to convert this uppercase string to a lowercase it is load. The function name is load. So I'm right here. Print phrase.

Phrase is the variable name that I have provided where I've stored the detail record of bye is good then give a dot and write, load. And after every function name I already told you that always give a first bracket. So it's done. Now just run it. See, it converted the uppercase string to lowercase. So this lower function will convert your upper case string to a lower case.

Now again, I write another phrase and give it a name of phrase one. So here also I write the same sentence. So now I'll write it in a lowercase. So Python is cool. I have written it, print this and see it's printing it lowercase. Now, I want to convert this to uppercase.

So here what I have to do in the print statement, I'm writing phrase one dogs offer a seat converted the whole text to uppercase. Now suppose you want to check whether the string that you have written or the string that is present is in uppercase or lowercase. So for that, what you can do is create another phrase called phrase to where I store a value, there is how you and I have to check whether this statement is in uppercase or in lowercase. So, we can just see from the text that is, this data is not in uppercase. So, to check something, whether it is in uppercase or in lowercase, we have to use a function. So, in this print statement, we'll use that particular function.

So, first print then within bracket right phrase to then dot ease Upper Gila first bracket, and here again, close the first bracket and run see it returns false. So this isn't logical operator is upper is checking whether your text is in uppercase, or in lowercase. So it returns false. It's a Boolean type data type, because it will return either true or false. So basically, this is a logical operation. Now here, suppose I'm creating another phrase.

Suppose phase three, and here I'm writing. What are you doing? Okay, now I will check whether this text is in lowercase or not. So I'll write print. phrase $3 is lowered, then the first bracket and the first bracket is closed and run so it returned Through that means this text is in lowercase. Now one of the interesting thing that I'll tell you now about this function here will combine two functions together.

Suppose this text What are you doing? This is not in uppercase, but I will create a function in such a way where I will use a function in such a way that it will first convert the text into uppercase and then it will return true when it will check that it is in uppercase or lowercase. So, here I will use phrase for equal to I use the same text. What are you doing? Now, here I will write print, right phrase for dot upper APA. So, in first convert the phrase for APA Case then.is awkward.

And now it will check whether it is in uppercase or in lowercase. So, just look at the function and the way I have written. So I have written print then the variable name then taught upper. So first thing what it will do is it will convert this phrase for to uppercase, and then it will check whether this text is in uppercase or not. So, can you guess what will be the result? Let's see seek return true because the first convert the whole text to uppercase and then it checked whether it is in uppercase or not.

So, after converting that whole text to uppercase, obviously it is an uppercase so it returned true. Same thing you can do for lowercase also. Okay, so the next function that we'll learn today is the length function. So what the scan function Window length function will tell you the length of the total text. So just create a text over here. So I'm writing text is equal to select anything over here.

So I'm right. Again, suppose Good morning. So now I want to know the total length of this text. So for this, I'll use the print function and within this print function, I'll use a function call length, and then the variable name. So run it and see it's turning 12 because the length of this text is 12. Now this counted 1234 include the space 5678 910 1112.

So 12 is the length so it returned 12 over here now a new problem. So create a phrase, right? All is well. Now, this is a new function that we'll be using. So write print, and then text and after text give a third bracket and write one what it will return. Let's see.

See it return L, this is basically l don't get confused with one this is not one this is L. So, if you are getting confused, then I must write something else over here. So I write for so what it returned it returned I do you know why it returned I, whenever I wrote for over here, because it is returning the fourth position letter from the F of text. Always remember one thing that machines start counting from 001 to this gap, is three and then the fourth letter is I saw it written it over here. So, if you change this to five it will return what s say it returned s, because starting from 01234 and five, the fifth letter is S. So here you were just providing the position and it will return the that letter that is present in the position it will return that particular letter.

Now, the next one, so, as this copy this text question over here and I write zero over here, see what it return it will return a because it start counting from zero now the next one. So here again, I'm write text one, and in this text one, I'll write a new day. And here I will use a new function called Sorry, I have to use a print function and within this print function I have to write text to one. And here I use a new function called index and within this index and write a word which what new I want to get the position of new from the above text. So I have written within quotes new. So run it and what it returned in return to because 01 and two, so this is the second word.

So it returned the position of new that is two. Now suppose you want to replace a word by a new word, then what can be done? So suppose text to is a new variable. So here I'm writing everything is lost. Next, I want to To replace this last word, we have a new word called fine. So I first have written everything is lost then I want to change, no, everything is not lost, everything is fine.

So I want to change this last to fine. So for that have to do replace function to text to dot replace, then write the word first you want to replace and then give a comma again within quotes right the new word that you want in place of last written, just run it, see what it returned, it returned, everything is fine. So you have replaced the word lost and you have changed it to fine. So in this way, you can replace a word with a new word. Always remember that write the word that you want to change first, and then the new word that you want in the second. So today, we have learned a few about functions, the few string functions basically.

So what are the functions we have learned the lower Upper East lower is the logical function length, then index, then replace. So these are the few functions that we have learned today. So I've just given you an idea on Python function. Now in the next video, we'll be starting with numerical functions. So I'll end my video over here. Goodbye.

See you in the next video. Thank you