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[no audio]

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Friends here we are going to discuss about

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what are the rules to create

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a pattern, such that you can use that pattern in your Regular

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Expressions. See already

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we know simply what is the RegEx or Regular Expression. See

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the 'regex' is a procedure in any language to look for a specified

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pattern in a given text.

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Now if you want to work with the Regular Expressions using

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your Python, then you have to use a module called 're',

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and that is the default module.

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So if you want to work with 're' in your scripts you have

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to import that. Simply 'import re'. Now in this 're' module you

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are having different types of operations.

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Now, I am going to show you some of them like, search, match,

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finditer, findall, sub, split, compile, right, and

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see as of now

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we are at very beginning stage to work with your Regular

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Expressions, that's why I am going to show you simple syntaxes

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for your 'search'.

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'match', 'finditer', and 'findall'. See

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this is one Regular Expression,

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and here we are using 'search' operation.

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Now the purpose of 'search'

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operation from your Regular Expression is different, same

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way the 'match' is different, 'finditer' is different, find all is different.

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But whatever it may be all these operations are going to

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use a called 'pattern'.

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Now before going to work with your Regular Expressions operations,

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first of all we should be good with 'pattern',

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I mean how to create a 'pattern', or

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what are the rules to create your 'pattern'.

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Right. Once if you are good with pattern, then you can very

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easily use your required operation from your RegEx or 're' module.

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So first I'm showing you very simple examples for your pattern.

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And already we know that guys, what is a pattern?

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Pattern is simply a sequence of characters which represent

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multiple strings. Now see that I am taking one of the pattern

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called "Python" inside of a quotation.

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First of all this is a string, your pattern, but this is

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normally a string, but whenever if you use this string

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inside of your Regular Expressions, then it is going to become a pattern.

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Now generally, I am saying that pattern is going to represent

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multiple strings.

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But of course sometimes your pattern is also going to represent

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only one string, no problem.

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But if you use your string inside of Regular Expressions,

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then this is going to become a pattern. Now this pattern is

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going to represent only one string,

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but if I take this pattern "python", in square brackets 2,

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and 3, '[23]'. First of all, this is a string. Normally this is

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a string, but if you use this string inside of your Regular Expressions,

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now it is going to become a pattern. Now if it is a

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pattern it is going to represent two strings, "Python2", and "Python3".

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That's it. Now here we have to know how the square brackets are going

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to work here. See based on square brackets

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now this entire string is going to represent two strings.

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That's why this is called a pattern.

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Now we have to learn this type of rules to create a pattern.

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Anyway, we will see them one by one, step by step, and guys

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sometimes for your pattern

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you can also use 'r', that is called 'raw string', but there

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is some purpose for that.

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We'll discuss that in your advanced level of your Regular

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Expressions. Now guys, just to get an idea on how to create

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a pattern or to understand the rules to create your pattern

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I am going to take one of the operations from your Regular

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Expressions that is called 'findall', because compared to all

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this 'findall' is very easy.

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So I'm going to take this operation just to give you

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clarity on to create rules for your patterns. Then later

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we will work with all operations.

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See once you are good with pattern, then we can work with

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any operation from your Regular Expressions.

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[no audio]

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Fine. Now see that.

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[no audio]

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'findall', this is one of the operations from your Regular Expression.

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Now how to use that 'findall'? Simply you have to import your

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're' module inside of your scripts on your command

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line. Then 're.findall(pattern,text)'.

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So this is your given text, in this text you are going to

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search for something, search for some string. That we are going

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to use, that we are going to find by using 'findall' operation

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from your 're'.

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So finally whatever you are going to get, that

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I'm printing. That's it.

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[no audio]

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Right. See that. Just to give simple idea

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I am going to write a simple

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[no audio]

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Python script. Let me save this.

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Of course, you can practice this on your command line as well.

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So 'practice_for_regex.py'. See first of all we are going

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to work with Regular Expressions in your Python.

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So we need to 'import re', and make sure that this is a default

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module. You don't need to install your 're' module, by default it

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is there with your Python.

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Now, first of all let me take 'my_str', or let me say simply

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'text'. You can take anything,

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this is just a variable.

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So, "This is a

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[no audio]

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python and it is easy to learn". That's it.

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This is my string.

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Now, my intention is, I want to search

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a string called "is" in

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a given text.

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See that. What I am doing is, simply I'm going to create

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'my_pat'. Pattern is nothing

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but, what is your required string.

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What is the required string you want to search in a given

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text, that is a pattern.

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So I want to search only "is".

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Now, let me simply 'print(re.findall())', your pattern in

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a given text.

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So guys these are the variables. So directly

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if you want to write your pattern here, and your text here

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you can write it. I will show you that as well.

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Now, let me run this and see the output. See in your entire text

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in how many places "is" there?

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See, guys be clear.

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We are not going to work with word. Word means, before your

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starting letter of a word

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you should have some space, after ending letter of your word

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you should have some space, then that is a word. But as of

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now you're not going to work with a word, you are going to

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work with a string. See

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"is" is there with the combination of this word, but we are looking

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just simply "is" string.

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So here "is" is there, here "is" is there, here "is" is there, so

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all those "is" you're getting. See what I am saying is, yeah

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while working with your Regular Expressions, directly

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you can write your pattern here and your text here. See

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I am going to write this thing.

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But instead of writing, just I stored in some variables, and

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now I am working with variables.

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There is no change. Right.

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Anyway, this is not a good practice. First store your text into

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some variable and your pattern into some

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variable then use that variable.

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[no audio]

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Fine. Now how it is going to work?

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Very simple. What is your pattern? "is".

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So two letters string you're searching. What your Python will

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do, from your given text it will take first two characters. Then

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is this, are these two characters equal to these two characters?

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No. That's why it will skip that part. Then it will take second

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character and third character,

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"h-i". Are they equal to "is"?

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No. Then it is going to skip. Then third and fourth it will

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take. Yes, "is" and "is". Now

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it is going to match your going to get. So likewise

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it is going to compare in your entire text, wherever there

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is a match for "is" those strings you are going to get.

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Be clear. Not a word, just simply you're going to match for a string.

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Even word is also a string.

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See, here "is" is a word but here "is" is not a word. That is a combination

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with some other word. But we are not looking for a word.

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We are looking for a string. That's it.

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Now, can you tell me, very simple logic here,

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[no audio]

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that is, how many times "is" is there in a given text?

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How many times "is" is there in a given text? See if you observe,

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the operation result, 'findall' operation result is a list

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no. We know the length we can find for a list by using 'len()'

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operation so that you can conclude that

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there are three "is" strings are there in a given text.

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It's very, very important one.

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[no audio]

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That's fine.

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[no audio]

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So first let me write once again, 'print(re.findall())',

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your pattern, given text.

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[no audio]

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Fine. Now my intention is, actually, the basic purpose of your Regular

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Expression is at a time

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if you want to search multiple strings, then we are going

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to work with Regular Expressions.

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Now I want to print

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from my given text wherever "is" is there, I mean "is" string

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and "it" string,

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all those things I want to print.

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See my intention, be clear,

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I want to search for "is" and "it" in a given

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text. So if "is" is there it has to print, if "it" is there it has

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to print. Suppose if "is" is there multiple times, all times

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it has to print. If "it" is there multiple times, all "its" it has to print.

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But now you have to understand that

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this, here you are having two strings,

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but from this you need to make a pattern

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such that that pattern has to represent these two strings,

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so that by using that pattern you can search in a given string

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for these two strings.

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See, if you observe first character is common

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no. That's why I can take simply "i". Then second character

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it maybe "s" or "t". So whenever there is a possibility of this

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one or that one then just simply write square brackets, inside

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of that just write

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"st" or "ts", no problem, both are same.

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Right. Now see that. What I am doing is, instead of "is",

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first character is "is", sorry "i", but second character

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maybe "s" or maybe "t".

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Now see the result - "is", "is", "it", "is".

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Yes, you are getting. But you don't need to follow order here.

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I mean first "s", second "t". No, not like that.

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You can also write "ts" also, no problem. See that.

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Now you are looking for a string which consists of

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two characters first of all,

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and that string, two character string

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maybe "is" or maybe "it". Now you are going to search for two

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strings with length of two, that means two characters in each

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string. Those strings are "it" and "is" in a given text. Now if

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they are in a given text then your 'findall' is going to find

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them. Let's say suppose

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I am trying to find,

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let me comment this, I want to find like

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'my_pat="x"'.

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Do you have "x" in your given text?

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No, that's why you're getting empty, '[]'.

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[no audio]

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Right. Do you have "a"? Yes. How many times "a" is there, that many

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number of times you are getting. Here "a"

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is there. Be clear. Very, very important. Here "a"

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is there, here "a" is there, here "a" is there.

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So wherever you have "a" all that "a" you are getting here.

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So if you go with advanced operations like 'search', 'findall',

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sorry, 'finditer',

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then you are going to get the index position as well.

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What is the index of first matching character, first

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matching string, and second matching string.

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We will see that in advanced level.

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So for time being we have to understand how to create a pattern.

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Now here I am going to show you the simple rules

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to create your pattern but this is just first level rules,

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basic rules.

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So we will see advanced level rules in next video. Fine.

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The very first thing is, suppose

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I want to match "a" with "a", then directly you have to write

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"a", there is no other option.

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I mean, suppose here I have written "a", right?

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So you are going to match "a" with "a", then you are getting.

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Suppose I want to match with some number, if number is there

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9 that to 9, if that 9 number is there in a given string, then, given

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string means text guys.

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In this 'text' variable if you have a 9, then Python

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will find that. But as of now, you don't have any 9 number

248
00:13:00,200 --> 00:13:02,200
in a given text, that's why it is not finding.

249
00:13:03,400 --> 00:13:06,200
So simple rule is, if you want to match with any particular

250
00:13:06,200 --> 00:13:08,800
character with particular character, then you

251
00:13:08,800 --> 00:13:11,400
need to directly write your pattern as that character only.

252
00:13:11,800 --> 00:13:12,900
Let's say somewhere

253
00:13:12,900 --> 00:13:14,100
I'm having "@".

254
00:13:15,200 --> 00:13:18,100
Now I want to search how many times "@"

255
00:13:18,100 --> 00:13:19,400
is there in a given text.

256
00:13:20,600 --> 00:13:22,100
See that. One time.

257
00:13:22,300 --> 00:13:23,400
Let me write somewhere

258
00:13:23,800 --> 00:13:26,200
once again this "@". Now

259
00:13:26,300 --> 00:13:29,500
let me rerun your code and see the result. In two places you

260
00:13:29,500 --> 00:13:31,800
have "@", now those two "@" you are getting.

261
00:13:31,800 --> 00:13:34,100
[no audio]

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00:13:34,100 --> 00:13:38,700
Fine. Now if you want to match any character with particular

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00:13:38,700 --> 00:13:42,900
character then you have to write that character itself.

264
00:13:43,600 --> 00:13:49,300
That is, anyway, we know that generally. Second rule, see just

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00:13:49,300 --> 00:13:55,000
now we have seen that if I write something like '[ts]' or '[st]',

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00:13:55,800 --> 00:14:00,800
what is the meaning for this? It is going to look for either

267
00:14:00,800 --> 00:14:07,000
"t" or for "s". But same way if I write '[abc]', if I write '[abc]' now it

268
00:14:07,000 --> 00:14:11,200
is going to look for either "a" or "b" or "c" in a given text.

269
00:14:11,200 --> 00:14:13,600
Let me show you that so that you can understand.

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00:14:14,200 --> 00:14:16,400
Suppose I am writing as of now

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00:14:16,400 --> 00:14:17,700
'my_pat="@"'.

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00:14:18,100 --> 00:14:22,400
Now your 'findall' is going to match or look in a given text only for "@".

273
00:14:23,000 --> 00:14:27,200
Now, what I am doing is, if I write something like "@a",

274
00:14:27,200 --> 00:14:31,000
what is the meaning for this? You are going to look for

275
00:14:31,000 --> 00:14:35,200
a string which consists of "@", and "a" immediately, side by side

276
00:14:35,200 --> 00:14:38,400
"@", and "a". Do you have anywhere in a given text? No, nowhere

277
00:14:38,400 --> 00:14:41,700
we have "@" and "a" immediately in a given text. Bow see

278
00:14:41,700 --> 00:14:47,200
the result, '[]'. But I want to look either for "@",

279
00:14:47,400 --> 00:14:49,400
or for "a", or for "s",

280
00:14:49,900 --> 00:14:53,500
you can write any number of characters inside of square brackets.

281
00:14:53,500 --> 00:14:57,800
Now the meaning is, assume that your Python is going to search

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00:14:57,800 --> 00:15:03,200
for "@", also for "a", and also for "s". Now see the result.

283
00:15:04,600 --> 00:15:06,800
How many times "s" is there? That many times you're going to

284
00:15:06,800 --> 00:15:09,700
get "s". How many times "a" is there? That many times you are

285
00:15:09,700 --> 00:15:12,100
getting. How many times "@" is there? You are getting.

286
00:15:13,800 --> 00:15:17,500
Now, first of all you're looking for only one character string

287
00:15:17,500 --> 00:15:21,100
in a given string. That character maybe "@", maybe

288
00:15:21,100 --> 00:15:22,100
"a", or maybe "s".

289
00:15:22,400 --> 00:15:24,700
So all these three are there some number of times, you're

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00:15:24,700 --> 00:15:27,300
going to get all of them that many number of times.

291
00:15:27,300 --> 00:15:29,900
[no audio]

292
00:15:29,900 --> 00:15:33,100
Right. Fine. Now see here.

293
00:15:33,100 --> 00:15:36,200
[no audio]

294
00:15:36,200 --> 00:15:40,600
So sometimes I want to, just assume that I want to look for

295
00:15:40,900 --> 00:15:44,800
either a or b or c or d or e or f.

296
00:15:44,800 --> 00:15:46,600
[no audio]

297
00:15:46,600 --> 00:15:51,100
So what is the meaning of, if you write any characters

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00:15:51,100 --> 00:15:53,900
inside of a square bracket means, first of all this entire

299
00:15:53,900 --> 00:15:55,300
thing is one character.

300
00:15:56,400 --> 00:16:01,500
But that character maybe "a" or maybe "b" or maybe "c", "d", likewise.

301
00:16:03,000 --> 00:16:05,500
So I can write in this way if I want to look for either "a"

302
00:16:05,500 --> 00:16:11,100
or "b" or "c" or "d" or "e" or "f", but all these are sequence characters,

303
00:16:11,100 --> 00:16:12,900
right, "a" to "f".

304
00:16:13,300 --> 00:16:14,700
So instead of writing in this way,

305
00:16:14,700 --> 00:16:18,400
there is a shortcut for this. You can also write simply "a-f".

306
00:16:19,500 --> 00:16:22,400
Now the meaning for this is you are going to look for one

307
00:16:22,400 --> 00:16:27,100
character string but that character maybe "a" or maybe "b", or

308
00:16:27,100 --> 00:16:28,300
up to "f".

309
00:16:28,500 --> 00:16:31,600
That's it. Now assume that

310
00:16:32,900 --> 00:16:33,900
something like this,

311
00:16:34,000 --> 00:16:36,200
I want to search a string,

312
00:16:36,200 --> 00:16:39,200
[no audio]

313
00:16:39,200 --> 00:16:52,000
let's say '[abcd, either "a" or "b" or "c" or "d", or some 'hijkl',

314
00:16:52,600 --> 00:17:00,000
or 'xyz]'. No spaces guys. Just assume that I have written

315
00:17:00,000 --> 00:17:04,800
'[abcd hijkl xyz]'. Now

316
00:17:04,800 --> 00:17:07,300
what is first of all the meaning for this? If you write anything

317
00:17:07,300 --> 00:17:11,800
inside of a square bracket, it is going to look

318
00:17:11,800 --> 00:17:16,200
for one character string, but that character maybe "a", or maybe

319
00:17:16,200 --> 00:17:18,598
"b", something like that from this group.

320
00:17:19,500 --> 00:17:23,500
But if you observe, first four characters are sequence, next

321
00:17:23,500 --> 00:17:26,000
five characters are also in sequence, next three characters

322
00:17:26,098 --> 00:17:28,098
are also sequence. In that case

323
00:17:28,098 --> 00:17:30,900
you can also write shortcut as 'a-d',

324
00:17:32,300 --> 00:17:39,400
now by default 'a-d' means '[abcd]'. Then '[h-l]'. The meaning

325
00:17:39,400 --> 00:17:45,300
for this is [hijkl]. Then '[x-z]'. Now the meaning for this

326
00:17:45,300 --> 00:17:49,000
is [xyz]'. Just for this, shortcut this is.

327
00:17:49,000 --> 00:17:50,900
[no audio]

328
00:17:50,900 --> 00:17:55,500
Right. Now see that. Let me take a given text.

329
00:17:57,000 --> 00:18:01,100
So my intention is, let me write a, let me comment this code

330
00:18:01,100 --> 00:18:04,900
as of now. Actually my intention is, just I want to look for

331
00:18:05,400 --> 00:18:06,900
either "a" or "b" or "c",

332
00:18:08,300 --> 00:18:14,700
or "d", let me take it. So 'my_pat', I want to look only for

333
00:18:14,900 --> 00:18:19,900
either A or B or C or D whenever if you want to look for

334
00:18:20,100 --> 00:18:23,100
either "a" or "b" or "c" or "d". Then you have to write your characters

335
00:18:23,100 --> 00:18:26,600
inside of square brackets. Now, let me 'print()',

336
00:18:29,100 --> 00:18:33,100
your operation is from 're.findall()', from your pattern,

337
00:18:33,900 --> 00:18:36,300
your given text. Now see the result.

338
00:18:38,000 --> 00:18:42,200
[abcd]. "c" is not there nowhere, and "b" also not there, but "a"

339
00:18:42,200 --> 00:18:46,300
and "d" is there, that's why you're getting that - 'a', 'a', 'd', 'a', 'a'.

340
00:18:49,000 --> 00:18:51,600
But the same thing I can also write '[a-d]'.

341
00:18:51,600 --> 00:18:53,700
[no audio]

342
00:18:53,700 --> 00:18:58,700
See the result. First two "a", one "d", two "a'. Now see the result,

343
00:18:58,700 --> 00:19:02,700
I am going to rerun by changing my pattern. Same thing you're

344
00:19:02,700 --> 00:19:08,600
getting. So this exactly equals to '[abcd]'.

345
00:19:09,500 --> 00:19:12,800
See sometimes you're going to look for any character, suppose '[a-z]',

346
00:19:13,100 --> 00:19:15,200
no need to write 'abcdefg' up to 'z'.

347
00:19:15,200 --> 00:19:18,200
Simply 'a-z' you can write. '[a-z]'. That's it.

348
00:19:18,200 --> 00:19:20,700
[no audio]

349
00:19:20,700 --> 00:19:22,000
So this is one of the rules.

350
00:19:23,100 --> 00:19:24,900
Then, so that's what I am giving here.

351
00:19:25,600 --> 00:19:28,700
So this already we discussed. Suppose if you have 'abcd',

352
00:19:28,700 --> 00:19:32,900
some 'hijk', and 'xyz', you can also write shortcut in this way.

353
00:19:33,900 --> 00:19:41,500
Now, let me take '\w'. Matches any single character, or digit,

354
00:19:41,500 --> 00:19:42,800
or underscore.

355
00:19:42,800 --> 00:19:44,700
[no audi]

356
00:19:44,700 --> 00:19:49,500
See that. See guys if I write simply pattern as 'a', "a" is going

357
00:19:49,500 --> 00:19:53,200
to match with only "a". Your 'findall' is going to look for this

358
00:19:53,200 --> 00:19:58,000
"a" in a given text for "a" only. But if you write instead

359
00:19:58,000 --> 00:20:02,000
of "a" if I write some special symbol called '\w', now the

360
00:20:02,000 --> 00:20:07,000
meaning for this is any alphabet from a to z, or

361
00:20:07,000 --> 00:20:13,400
capital A to Z, then number 0 to 9 or maybe underscore also.

362
00:20:13,400 --> 00:20:15,300
[no audio]

363
00:20:15,300 --> 00:20:19,900
See suppose if we have a text called 'abc', and if I write a

364
00:20:19,900 --> 00:20:23,700
pattern "a", now if I look into this "a" is going to get only

365
00:20:23,700 --> 00:20:29,000
one time, but if I write in place of "a", '\w', "a" is also a '\w\,

366
00:20:29,200 --> 00:20:33,100
or "b" also comes under '\w', "c" also comes under '\w'. Now you're

367
00:20:33,100 --> 00:20:37,600
going to get three characters because '\w' means any any alphabet,

368
00:20:38,200 --> 00:20:40,300
and number, and one underscore as well.

369
00:20:41,100 --> 00:20:43,600
Let me show you this on your script.

370
00:20:45,800 --> 00:20:47,200
See my intention is,

371
00:20:48,800 --> 00:20:50,000
let me take, now,

372
00:20:50,000 --> 00:20:51,700
first of all let me comment this code.

373
00:20:53,000 --> 00:20:54,000
Guys be clear,

374
00:20:54,000 --> 00:20:57,500
[no audio]

375
00:20:57,500 --> 00:21:01,700
I am going to take 'my_pat' as 're', sorry.

376
00:21:03,200 --> 00:21:05,600
I'm not taking raw string as of now, but we have to take

377
00:21:05,600 --> 00:21:08,700
it. I will tell you when you have to take 'r'. Fine.

378
00:21:09,800 --> 00:21:11,900
Now, what I am doing simply I am writing '\w'.

379
00:21:13,500 --> 00:21:18,900
Now see the result. If I do 'print(re.findall())', your

380
00:21:18,900 --> 00:21:22,300
pattern, in a given text, see the result.

381
00:21:23,600 --> 00:21:27,500
You're going to get all matching things except space.

382
00:21:27,500 --> 00:21:32,400
Are we getting space matching? See after this "is", between "This"

383
00:21:32,400 --> 00:21:35,200
and "is", we have a space. Are we getting a space anywhere here?

384
00:21:35,300 --> 00:21:39,200
No, because space does not come under '\w',

385
00:21:39,300 --> 00:21:41,100
that's why you're not getting matching for that.

386
00:21:42,500 --> 00:21:46,400
And "@" does not comes under the your '\w', that's why this

387
00:21:46,400 --> 00:21:49,400
is not a match for your '\w'. That's why you're not getting

388
00:21:49,400 --> 00:21:53,500
that. Let me write somewhere "-", and let me write somewhere

389
00:21:53,500 --> 00:21:56,000
"_". Now see the result.

390
00:21:57,100 --> 00:22:00,200
You're getting "_". Between "o", and "l", there is

391
00:22:00,200 --> 00:22:03,900
an "_", but between "o" and "_" you have a

392
00:22:03,900 --> 00:22:05,800
space, that space is not a match.

393
00:22:06,400 --> 00:22:10,800
You're not getting that. And "-" does not come under this

394
00:22:10,800 --> 00:22:14,600
'\w', but "_" comes under '\w', that's why you are getting here.

395
00:22:14,600 --> 00:22:16,500
[no audio]

396
00:22:16,500 --> 00:22:21,500
Now I am looking for two letter string or two character

397
00:22:21,500 --> 00:22:25,800
string. If I write '\w\w', the meaning for that is just

398
00:22:25,800 --> 00:22:31,300
assumption. "a" means, sorry, '\w' means 'a-z' small letters,

399
00:22:31,300 --> 00:22:35,100
and 'A-Z' capital letters, and numbers 0 to 9, and underscore.

400
00:22:35,600 --> 00:22:39,600
Now if I write two '\w' the meaning for that is, it may be

401
00:22:39,600 --> 00:22:46,600
'aa', 'ab', 'ac', likewise 'A-Z' and 'ba', 'bb', 'bc',

402
00:22:46,600 --> 00:22:53,500
likewise, or maybe 'a0', 'a1', 'a2' up to 'a9', or 'a_',

403
00:22:54,400 --> 00:22:57,700
right, 'b_', 'c_', likewise you are going to get

404
00:22:57,700 --> 00:23:00,500
number of combinations. Among all those combinations

405
00:23:01,700 --> 00:23:04,800
whatever matching is there in a given string you're going to get them.

406
00:23:06,400 --> 00:23:10,600
See if I write '\w\w' the meaning for that is, you're going

407
00:23:10,600 --> 00:23:16,000
to look for a string which consists of two characters.

408
00:23:17,100 --> 00:23:22,000
Now if I run this, see "th" is also one match for this. First,

409
00:23:22,000 --> 00:23:24,000
let me run this and see the output so that you can understand.

410
00:23:24,100 --> 00:23:27,000
See that. "Th", two letter string,

411
00:23:27,000 --> 00:23:31,200
yes, match. That's why we are getting that. "is", yes you are getting,

412
00:23:31,900 --> 00:23:35,700
then "is" you're, in between you have a space, right, space does not

413
00:23:35,700 --> 00:23:38,500
come under your '\w', that's why you are not getting that. "is",

414
00:23:38,500 --> 00:23:44,100
yes you are getting. See "a" is only one single character. Before

415
00:23:44,100 --> 00:23:45,700
"a" and after "a" you have a space.

416
00:23:46,600 --> 00:23:49,900
So combination with "a", you don't have any valid character

417
00:23:49,900 --> 00:23:51,600
which comes under '\w'.

418
00:23:52,700 --> 00:23:56,500
In case if space comes under '\w', you're going to get "a "

419
00:23:56,500 --> 00:24:00,700
also, but space not comes under '\w' matching,

420
00:24:00,800 --> 00:24:05,500
that's why for "a" you don't have any combination to get two

421
00:24:05,500 --> 00:24:06,500
character strings.

422
00:24:06,500 --> 00:24:09,200
That's why this is not going to match for your pattern.

423
00:24:09,200 --> 00:24:13,000
[no audio]

424
00:24:13,000 --> 00:24:19,100
Right. And one more thing, see that last "le" suppose, two

425
00:24:19,100 --> 00:24:23,700
character string, "ar", two character string, but for "n"

426
00:24:23,700 --> 00:24:27,300
you don't have again any matching to get a two character string.

427
00:24:27,500 --> 00:24:30,000
After "n" suppose if we have any character,

428
00:24:30,000 --> 00:24:33,900
let's say "a", now if I run this. See the last thing, you're

429
00:24:33,900 --> 00:24:37,900
getting "ar". After "ar" now I already here you "a" letter,

430
00:24:38,000 --> 00:24:41,800
"a" character. Now if I rerun you're going to get "na" also.

431
00:24:42,600 --> 00:24:45,200
Not only "a", you can take "_" also, because "_"

432
00:24:45,200 --> 00:24:46,800
also comes under '\w',

433
00:24:47,000 --> 00:24:49,700
you are going to get matched by using these two characters

434
00:24:49,700 --> 00:24:54,700
combination. Now, let me write three, three character

435
00:24:56,300 --> 00:24:57,800
matching. Guys,

436
00:24:57,900 --> 00:25:00,500
now the meaning for this is, you're going to look for a string

437
00:25:00,500 --> 00:25:03,700
which consists of three characters, but what are those three

438
00:25:03,700 --> 00:25:09,600
characters? We know '\w' means any character 'a-z' small or

439
00:25:09,600 --> 00:25:14,200
capital, 0 to 9, and underscore. Only from these three groups

440
00:25:14,600 --> 00:25:17,300
it is going to look for three character string.

441
00:25:17,800 --> 00:25:22,300
Now, let me run this and see the result. "thi" three-letter character,

442
00:25:22,300 --> 00:25:26,100
yes, you are getting. But for "s", after that you have a space,

443
00:25:26,300 --> 00:25:29,900
so space does not come under '\w', that's why there is no possibility

444
00:25:29,900 --> 00:25:33,900
for this "s" to make three letter character. Then it is going

445
00:25:33,900 --> 00:25:37,500
to skip. Then for "is" you have only two characters, but you

446
00:25:37,500 --> 00:25:40,800
don't have any three characters string, because if you want

447
00:25:40,800 --> 00:25:43,900
to get a three character string here we have a space, but

448
00:25:43,900 --> 00:25:46,900
space does not come under '\w', that's why you're not getting

449
00:25:46,900 --> 00:25:50,000
a part for this. Same way for "a" you don't have any three character

450
00:25:50,000 --> 00:25:52,100
string, but "python", "pyt",

451
00:25:53,600 --> 00:25:57,900
three characters, valid characters, "hon", three characters. That's why

452
00:25:57,900 --> 00:26:02,000
you are getting that. "and", three characters. For "it"

453
00:26:02,000 --> 00:26:03,600
you don't have any valid three characters,

454
00:26:03,600 --> 00:26:08,000
that's why you're not getting. "eas", yes, "e-a-s", three characters,

455
00:26:08,000 --> 00:26:11,400
but for "y" we don't have any three character string combination,

456
00:26:11,400 --> 00:26:15,300
that's why this is not a part. Likewise you are getting. I

457
00:26:15,300 --> 00:26:16,500
hope you're good with this.

458
00:26:16,500 --> 00:26:18,300
[no audio]

459
00:26:18,300 --> 00:26:22,000
Now, let me go with the capital '\W' - Matches

460
00:26:22,000 --> 00:26:24,600
any character not part of '\w'.

461
00:26:26,000 --> 00:26:28,400
See whatever you have in this '\w',

462
00:26:29,100 --> 00:26:33,000
other than that all are going to come under '\W'. See that.

463
00:26:34,400 --> 00:26:35,900
Now, let me comment this.

464
00:26:35,900 --> 00:26:41,100
[no audio]

465
00:26:41,100 --> 00:26:43,200
First let me take 'my_pat' as small,

466
00:26:43,200 --> 00:26:45,900
[no audio]

467
00:26:45,900 --> 00:26:51,300
'\w' only, and see the result first. 'print(re.findall())'. Guys

468
00:26:51,300 --> 00:26:54,000
you can get clarity by doing practice.

469
00:26:54,100 --> 00:26:55,300
Please do same thing

470
00:26:55,600 --> 00:26:59,300
once, I mean whatever we've done here same thing you just practice

471
00:26:59,300 --> 00:27:02,600
once, and try to understand how you're going to get your output.

472
00:27:02,600 --> 00:27:04,800
[no audio]

473
00:27:04,800 --> 00:27:08,100
Now, let me run this and see the output. But if I make it

474
00:27:08,100 --> 00:27:13,100
as a capital '\W', see "T" and "h", "i", "s", whatever you are getting here

475
00:27:13,100 --> 00:27:15,500
no, these are not the part of '\W'.

476
00:27:15,500 --> 00:27:16,900
They are part of '\w'.

477
00:27:17,500 --> 00:27:20,600
That's why if I write '\W', see what you are going to

478
00:27:20,600 --> 00:27:24,900
get. You're going to get spaces, "@", and "-", because

479
00:27:24,900 --> 00:27:27,500
these are not the part of your '\w'.

480
00:27:29,000 --> 00:27:33,100
It is going to look for a character which is not there in

481
00:27:33,100 --> 00:27:34,700
this group, '\w' group.

482
00:27:36,400 --> 00:27:41,100
Space is the match for '\W', "@" is the match

483
00:27:41,100 --> 00:27:42,100
for '\W'.

484
00:27:42,500 --> 00:27:44,900
See how many spaces are there, all those spaces you are

485
00:27:44,900 --> 00:27:45,900
going to get here.

486
00:27:46,900 --> 00:27:48,800
So that is the use of '\W'.

487
00:27:48,800 --> 00:27:53,500
Simply the members which are there in this, other

488
00:27:53,500 --> 00:27:56,200
than that remaining all come under '\W'.

489
00:27:56,700 --> 00:27:58,000
Very, very important.

490
00:27:59,300 --> 00:28:03,200
Then '\d' - Matches a decimal digit 0-9,

491
00:28:03,200 --> 00:28:07,800
any number. See any way by default '\w'

492
00:28:07,800 --> 00:28:11,800
means it also includes your numbers but along with the numbers

493
00:28:11,800 --> 00:28:15,400
'\w' includes alphabets and underscore. But I want to match

494
00:28:15,400 --> 00:28:16,700
with only numbers.

495
00:28:17,500 --> 00:28:21,300
Let's say I have somewhere, let me write "PYTHON3".

496
00:28:21,300 --> 00:28:25,200
[no audio]

497
00:28:25,200 --> 00:28:26,200
"python3",

498
00:28:27,100 --> 00:28:29,500
and let's say, somewhere just for, here

499
00:28:29,500 --> 00:28:31,600
I am writing "python2", and somewhere

500
00:28:31,600 --> 00:28:33,600
I'm writing some number let's say 4.

501
00:28:35,200 --> 00:28:39,100
Okay. Now what I am doing is, I am going to take a pattern as some

502
00:28:39,100 --> 00:28:43,700
'\d'. You know what is meant by '\d'. Any number 0 to 9.

503
00:28:44,200 --> 00:28:49,900
See I'm going to take pattern as '\d', and let me print it.

504
00:28:51,100 --> 00:28:53,700
're.findall()'. Sorry.

505
00:28:54,800 --> 00:28:57,700
'findall()', your pattern, in a given text.

506
00:28:58,200 --> 00:29:01,000
So wherever number is there, because you're looking for only

507
00:29:01,000 --> 00:29:02,400
one number, one string,

508
00:29:02,400 --> 00:29:06,900
sorry, a character which consists of only one digit, string

509
00:29:06,900 --> 00:29:10,400
which consists of only one character that is a digit. Now

510
00:29:10,400 --> 00:29:12,600
see the result. [2, 4, 3]. Yes,

511
00:29:12,600 --> 00:29:16,100
we have somewhere [2, 4, 3]. You are getting that. Now my intention

512
00:29:16,100 --> 00:29:21,700
is, "python" with some number. So before '\d'

513
00:29:21,700 --> 00:29:25,500
I should have a word called "python", after that any number

514
00:29:25,500 --> 00:29:27,200
maybe 2 or 3. Now,

515
00:29:27,200 --> 00:29:30,600
if I run this you are going to get "python", after that number

516
00:29:30,600 --> 00:29:34,600
is there, no. Now this is the match for this pattern. At

517
00:29:34,600 --> 00:29:39,600
the same time "python3" is also match for '\d'. Suppose

518
00:29:39,600 --> 00:29:44,300
if I write only "python2", you're going to get only "python2"

519
00:29:44,300 --> 00:29:48,600
because directly you're mentioning match "2" with "2", "python2"

520
00:29:48,600 --> 00:29:54,200
with "python2". But I want to match with "python\d" means,

521
00:29:54,700 --> 00:29:58,400
the meaning for this, it is going to represent "python0",

522
00:29:58,400 --> 00:30:02,000
"python1", "python2", "python3", up to "python9". But among

523
00:30:02,000 --> 00:30:05,100
all those whatever the strings are there in a given text

524
00:30:05,100 --> 00:30:08,000
those things, those strings only it is going to match.

525
00:30:08,900 --> 00:30:09,900
That's it.

526
00:30:09,900 --> 00:30:13,400
[no audio]

527
00:30:13,400 --> 00:30:16,200
Right. Now let's say instead of this pattern

528
00:30:16,500 --> 00:30:17,800
I want to look for

529
00:30:20,600 --> 00:30:25,500
a string which consists of two digits. Do we have anything

530
00:30:25,500 --> 00:30:29,000
in this? No. Sequentially,

531
00:30:29,000 --> 00:30:31,700
I mean immediately two digits nowhere we are having. That's

532
00:30:31,700 --> 00:30:33,700
why you're not getting that. Let's say I want to write here

533
00:30:33,700 --> 00:30:37,900
45, something. Now you are getting that because two digits are

534
00:30:37,900 --> 00:30:41,300
there. You're looking for '\d\d' means a string

535
00:30:41,300 --> 00:30:43,200
which consists of two digits.

536
00:30:43,600 --> 00:30:44,600
Yes you are getting.

537
00:30:46,100 --> 00:30:48,500
Now, so in this basic rules, let me go

538
00:30:48,500 --> 00:30:50,100
with the last one, '.'.

539
00:30:51,700 --> 00:30:55,800
Very, very important one, at the same time confusion one. Very

540
00:30:55,800 --> 00:31:01,100
useful in your real-time, '.'. '.' matches any single character,

541
00:31:01,100 --> 00:31:03,100
except new line character.

542
00:31:03,100 --> 00:31:05,200
[no audio]

543
00:31:05,200 --> 00:31:10,200
See if you take '\W', other than this members all comes

544
00:31:10,200 --> 00:31:11,800
under '\W'.

545
00:31:12,100 --> 00:31:16,400
But if you go with the '.', all valid characters which are

546
00:31:16,400 --> 00:31:20,100
there in your keyboard or which are there in your computer

547
00:31:20,100 --> 00:31:23,400
language, all are going to match with your '.' except new

548
00:31:23,400 --> 00:31:25,100
line. See that.

549
00:31:25,100 --> 00:31:28,100
[no audio]

550
00:31:28,100 --> 00:31:30,600
Let me comment this things first.

551
00:31:30,600 --> 00:31:34,200
[no audio]

552
00:31:34,200 --> 00:31:37,000
Guys these are very basic rules to create your patterns.

553
00:31:37,000 --> 00:31:38,400
We have advanced levels as well,

554
00:31:38,400 --> 00:31:40,500
we will see them in our next video.

555
00:31:42,200 --> 00:31:45,400
So now my intention is, I am taking a pattern as

556
00:31:45,400 --> 00:31:47,400
[no audio]

557
00:31:47,400 --> 00:31:52,900
'.' means, match with any character. Now see that what you are going to get.

558
00:31:52,900 --> 00:31:55,500
[no audio]

559
00:31:55,500 --> 00:32:03,100
Your pattern, 'text'. All we are going to get. See that. We're

560
00:32:03,100 --> 00:32:05,400
going to get each and every character which is there in a given

561
00:32:05,400 --> 00:32:09,500
text. Anyway, we don't have any '\n', I mean new line in our

562
00:32:09,500 --> 00:32:13,200
given text, except that that is going to match all things.

563
00:32:13,600 --> 00:32:18,400
Now if you observe "T", "h", "i", "s", after that space is there in a given

564
00:32:18,400 --> 00:32:21,800
text. Yes, that space is also matching for '.'. '.' means,

565
00:32:21,800 --> 00:32:25,000
a '.' means anything simply other than '\n'.

566
00:32:26,500 --> 00:32:28,600
Now I want to match

567
00:32:29,000 --> 00:32:32,500
any two characters, then write two '.'. Now see the result.

568
00:32:33,600 --> 00:32:35,500
I want to match for three '.',

569
00:32:35,600 --> 00:32:39,000
I mean any three characters, any three symbols which are there

570
00:32:39,000 --> 00:32:40,300
in computer language.

571
00:32:41,200 --> 00:32:42,200
See that.

572
00:32:43,800 --> 00:32:46,300
"33" you're going to get. Now

573
00:32:46,300 --> 00:32:50,300
my intention is, I want to match '.' with '.' only.

574
00:32:50,300 --> 00:32:52,100
[no audio]

575
00:32:52,100 --> 00:32:56,600
Generally '.' means, in your pattern '.' means for any matching

576
00:32:57,100 --> 00:33:00,300
except new line. But I want to match '.' with '.'.

577
00:33:00,500 --> 00:33:06,200
Let's say in a given text somewhere I have '.', "python 2."

578
00:33:07,100 --> 00:33:09,100
Now if I run this what you are getting?

579
00:33:09,100 --> 00:33:11,100
[no audio]

580
00:33:11,100 --> 00:33:14,100
See now you're also going to get somewhere "." also.

581
00:33:15,600 --> 00:33:16,600
You're looking for

582
00:33:16,600 --> 00:33:18,600
[no audio]

583
00:33:18,600 --> 00:33:21,800
three digit string, yes.

584
00:33:22,100 --> 00:33:23,500
Sorry, three character string.

585
00:33:23,500 --> 00:33:27,700
Yes, you are getting, 'n2.'. But along with the '.' you're also

586
00:33:27,700 --> 00:33:28,700
getting some other strings

587
00:33:28,700 --> 00:33:30,100
no, but I don't want to get them.

588
00:33:30,100 --> 00:33:32,500
I want to get exactly '.' with '.' only.

589
00:33:32,600 --> 00:33:34,500
I want to match my '.' with '.'.

590
00:33:35,300 --> 00:33:39,700
See if you remember, if you want to match "a" with "a", let's say

591
00:33:39,700 --> 00:33:41,000
this is your text "abc".

592
00:33:41,400 --> 00:33:44,400
This is your text, and you want to write a pattern. How you

593
00:33:44,400 --> 00:33:46,600
can write a pattern if you want to match "a" with "a"?

594
00:33:46,700 --> 00:33:47,800
"a" only you're writing.

595
00:33:48,400 --> 00:33:51,500
Now in my text somewhere I have '.', but I want to match

596
00:33:51,500 --> 00:33:55,100
"." with ".". Simply if I write ".", "." is going to match with

597
00:33:55,100 --> 00:33:56,100
any character.

598
00:33:56,300 --> 00:33:59,800
But I want to match this "." with this "." only. At that time

599
00:33:59,800 --> 00:34:04,100
you have to escape your special purpose of your "." by placing

600
00:34:04,200 --> 00:34:05,200
'\' symbol.

601
00:34:06,100 --> 00:34:07,100
Let me run this.

602
00:34:07,100 --> 00:34:09,500
[no audio]

603
00:34:09,500 --> 00:34:12,100
'\.', now see the result.

604
00:34:12,100 --> 00:34:14,100
[no audio]

605
00:34:14,199 --> 00:34:19,100
Let me write some other ways, in other places ".".

606
00:34:19,100 --> 00:34:21,100
See that. That's it.

607
00:34:21,100 --> 00:34:23,400
[no audio]

608
00:34:23,400 --> 00:34:27,000
But if I remove this '\', now you're going to get all characters

609
00:34:27,000 --> 00:34:29,500
which are going to match for your ".". By simply "." means

610
00:34:29,500 --> 00:34:31,400
anything. That's it. Except new line.

611
00:34:32,199 --> 00:34:33,500
So it's very, very important guys.

612
00:34:33,500 --> 00:34:36,100
If you want to match "." with ".", you have to use in your

613
00:34:36,100 --> 00:34:37,500
pattern '\.'.

614
00:34:38,300 --> 00:34:39,900
Very, very useful example

615
00:34:39,900 --> 00:34:42,199
I am going to give in your real time.

616
00:34:43,000 --> 00:34:45,900
Let's say you have a text in this way.

617
00:34:47,500 --> 00:34:51,000
"This is my ip of a db server.

618
00:34:51,800 --> 00:34:56,199
Guys just assume that some, '255.',

619
00:34:57,500 --> 00:34:58,500
let's say

620
00:34:58,500 --> 00:35:00,800
[no audio]

621
00:35:00,800 --> 00:35:01,800
'100.'

622
00:35:01,800 --> 00:35:04,000
[no audio]

623
00:35:04,000 --> 00:35:06,400
'102.' Of course

624
00:35:06,400 --> 00:35:08,400
[no audio]

625
00:35:08,400 --> 00:35:12,699
as of now I am taking in my IP in all places, in all places three digits.

626
00:35:14,000 --> 00:35:17,900
But see, you may have sometimes here only two digits or one digit, right.

627
00:35:18,500 --> 00:35:21,699
But as of now based on our rules, if I go with this example

628
00:35:21,699 --> 00:35:23,000
you can understand. Later

629
00:35:23,000 --> 00:35:24,699
we will see in our advanced level

630
00:35:25,199 --> 00:35:27,800
if you have only one digit here how to match, everything

631
00:35:27,800 --> 00:35:31,600
we will see. Now I am going to tell you one important thing

632
00:35:31,600 --> 00:35:32,600
from your real time.

633
00:35:33,100 --> 00:35:36,100
See you are going to run some script, or some information

634
00:35:36,100 --> 00:35:38,800
is there somewhere in your text file, and you are going to

635
00:35:38,800 --> 00:35:42,400
read that, but you don't know where your IP is there.

636
00:35:44,199 --> 00:35:47,800
Assume that you're getting some output somewhere. In that

637
00:35:47,800 --> 00:35:51,800
output you have IP, but you don't know where exactly your IP is there,

638
00:35:51,800 --> 00:35:54,100
[no audio]

639
00:35:54,100 --> 00:35:57,200
where exactly your IP is there but I want to fetch only my

640
00:35:57,200 --> 00:36:00,000
IP. How you can write a pattern?

641
00:36:01,100 --> 00:36:05,500
See, I can write a pattern, any variable, just take any variable.

642
00:36:05,500 --> 00:36:08,300
I am taking simply now 'pat' or 'my_pat', or 'pat', or

643
00:36:08,300 --> 00:36:12,900
'x=', also you can take. See as of now

644
00:36:12,900 --> 00:36:16,300
I am assuming that in my IP in all places three digit number

645
00:36:16,300 --> 00:36:20,100
is there. That's why '\d\d\d' means,

646
00:36:20,100 --> 00:36:22,800
[no audio]

647
00:36:22,800 --> 00:36:24,200
you are looking for

648
00:36:24,200 --> 00:36:27,200
three digit string in a given text.

649
00:36:28,200 --> 00:36:31,700
But first let me run this so that you can understand.

650
00:36:31,700 --> 00:36:34,000
[no audio]

651
00:36:34,000 --> 00:36:35,100
What happened? Yeah.

652
00:36:35,300 --> 00:36:39,800
Sorry, I have written at the end one more extra '\'. Fine. Now see that.

653
00:36:40,900 --> 00:36:44,800
'findall()', your pattern, your text.

654
00:36:45,900 --> 00:36:46,900
See the output.

655
00:36:46,900 --> 00:36:49,000
[no audio]

656
00:36:49,000 --> 00:36:53,200
Okay, let me write three digits. Now see the output. '255',

657
00:36:53,200 --> 00:36:55,800
'100', '102', '103', you're getting separately.

658
00:36:55,800 --> 00:36:57,500
But this entire thing is one IP.

659
00:36:57,500 --> 00:37:01,900
I want to get as only one value, not like this. Then what I have to do?

660
00:37:02,800 --> 00:37:06,400
I want to write a pattern such that it is going to match with this thing.

661
00:37:07,500 --> 00:37:10,800
I don't know exact number what is there but I know in each and every

662
00:37:10,800 --> 00:37:19,600
position there are three digits then three '\d\d\d', then '.\d\d\d

663
00:37:19,600 --> 00:37:26,200
.\d\d\d.\d\d\d'

664
00:37:27,300 --> 00:37:28,300
Now see the output.

665
00:37:28,900 --> 00:37:30,100
It's working perfectly, right?

666
00:37:30,100 --> 00:37:32,100
[no audio]

667
00:37:32,100 --> 00:37:35,700
It's working perfectly. Now see the magic.

668
00:37:37,300 --> 00:37:38,300
Now let's say

669
00:37:38,300 --> 00:37:42,600
[no audio]

670
00:37:42,600 --> 00:37:47,900
here instead of '\d', what I am doing is '\w' I am writing.

671
00:37:47,900 --> 00:37:51,300
[no audio]

672
00:37:51,300 --> 00:37:54,500
Just assume that. Because under '\w'

673
00:37:54,500 --> 00:37:56,000
you're also going to get digits, right?

674
00:37:56,000 --> 00:38:00,000
[no audio]

675
00:38:00,000 --> 00:38:01,600
Now see the result what you are getting.

676
00:38:02,700 --> 00:38:03,700
You are getting.

677
00:38:05,000 --> 00:38:10,600
Now I am writing "this", something, in this

678
00:38:10,600 --> 00:38:13,300
way I'm writing. Now see the result what you are getting.

679
00:38:13,300 --> 00:38:16,800
[no audio]

680
00:38:16,800 --> 00:38:18,000
Nowhere you have "." here

681
00:38:18,000 --> 00:38:23,000
no, then why it is matching with your given pattern? Because

682
00:38:23,000 --> 00:38:27,100
"." means anything, but I want to match "." with "." only.

683
00:38:28,800 --> 00:38:30,900
I want to match "." with "." only.

684
00:38:32,100 --> 00:38:35,700
Otherwise, let me take in terms of numbers only so that you will get idea.

685
00:38:36,300 --> 00:38:39,400
Let's say 1, 2, 3.

686
00:38:39,400 --> 00:38:41,900
[no audio]

687
00:38:41,900 --> 00:38:43,000
One extra number.

688
00:38:43,000 --> 00:38:44,300
Let me write some numbers,

689
00:38:44,300 --> 00:38:46,400
[no audio]

690
00:38:46,400 --> 00:38:47,400
some number.

691
00:38:47,400 --> 00:38:49,200
[no audio]

692
00:38:49,200 --> 00:38:51,400
This is not IP, right, but I'm writing some number.

693
00:38:52,400 --> 00:38:54,400
Now let me write instead of this thing.

694
00:38:55,500 --> 00:38:59,200
Guys be clear why I am giving this means, in your real time

695
00:38:59,200 --> 00:39:01,800
you're going to get sometimes confusion, for that

696
00:39:02,200 --> 00:39:05,700
I am giving some clarity here to use your '\d'.

697
00:39:05,700 --> 00:39:08,900
[no audio]

698
00:39:08,900 --> 00:39:12,900
Now if I run this, see the output. This is IP, but this is

699
00:39:12,900 --> 00:39:13,900
not a IP right?

700
00:39:15,100 --> 00:39:18,800
Our intention is, three digits, then '.', three digits, then

701
00:39:18,800 --> 00:39:22,800
'.', three digits, then '.', three digits. In this way if

702
00:39:22,800 --> 00:39:25,400
I have any string in a given text that only I want to fetch.

703
00:39:25,400 --> 00:39:29,100
Yes, I'm fetching that. Along with that why I'm getting this?

704
00:39:30,700 --> 00:39:33,100
See now you are not matching "," with ".".

705
00:39:33,700 --> 00:39:37,700
If you want to match this "." with this ".", you don't

706
00:39:37,700 --> 00:39:39,700
write '.', you have to write '\.'.

707
00:39:40,900 --> 00:39:44,500
Simply if I write a '.', '.' means any digit, any character.

708
00:39:44,900 --> 00:39:47,900
That's why see '\d\d\d', this is going to match for

709
00:39:47,900 --> 00:39:49,100
first three digits.

710
00:39:49,600 --> 00:39:50,600
Then '.' means anything

711
00:39:50,600 --> 00:39:53,900
no. Now this is also going to match. Again three digits.

712
00:39:53,900 --> 00:39:57,500
Yes, three digits. Then "." means anything. '5' is also going

713
00:39:57,500 --> 00:40:01,000
to match for ".". But our intention is not for this type

714
00:40:01,000 --> 00:40:05,800
of numbers. Some three digits, then ".", some three digits, then

715
00:40:05,800 --> 00:40:09,600
".", then some three digits, ".", likewise.

716
00:40:09,600 --> 00:40:13,000
That's why if you want to match "." with ".",

717
00:40:13,200 --> 00:40:15,400
you have to use '\.'.

718
00:40:16,100 --> 00:40:17,800
That's it. Now see the result.

719
00:40:17,800 --> 00:40:20,000
[no audio]

720
00:40:20,000 --> 00:40:23,300
So that's why there is a small difference between '.' and

721
00:40:23,300 --> 00:40:25,400
'\.'. You need to understand that clearly.

722
00:40:27,000 --> 00:40:30,600
Simple thing, I want to match "." with "." only, then you

723
00:40:30,600 --> 00:40:31,900
have to write '\.'. That's it.

724
00:40:33,300 --> 00:40:35,700
Okay. Okay guys, don't get confused.

725
00:40:36,000 --> 00:40:39,500
We are going to practice with number of examples so that

726
00:40:39,500 --> 00:40:42,000
you will get good idea about your Regular Expressions.

727
00:40:42,200 --> 00:40:44,200
So as of now, these are the simple

728
00:40:45,300 --> 00:40:48,000
rules to create your pattern. In next video

729
00:40:48,000 --> 00:40:52,500
we'll discuss about advanced level rules to create your pattern.

730
00:40:53,500 --> 00:40:55,200
Okay, thank you for watching this video.

731
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