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Hello and welcome to this video.

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In this video I'm going to introduce you to if statements if statements are basically conditional statements

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that means they are statements that only execute based on certain conditions.

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If statements are important aspects of the control flow of the program they help you make important

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decisions in your programs.

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They only run the code in the if block when the condition is true.

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So when you write an if statement you'll have a block of code that you want to execute.

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If the condition that you have set is met so only that particular code will execute if the condition

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is not met then nothing runs that code does not execute.

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If statements normally can use comparison and logical operators to check if certain conditions have

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been met or not this is a basic syntax for writing and if statement so you have the if keyword and then

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inside the parentheses you just specify the conditions and then you have this call on here.

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This cologne is very important.

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It tells the Python interpreter that you are starting a new line of code.

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So when you have this call on here it intent if you have a good text editor it will automatically indent

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into a new line that enables you to write some new line of code.

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So whatever code you're right here in the indented block that is the code that will run or execute if

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the condition that you have set in the F block is met to illustrate how the if statement works.

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I'm going to create a new file inside my PI charm idc.

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So I've already got a directory with some Python files so I'm just going to right click on my directory

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and go new and click on Pipeline file.

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I'm just going to call it if I need to save it as a python file with a top P Y extensions are quick.

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OK so now I've created a new file.

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The first thing I want to do is create a couple of variables.

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So I'm going to create a variable I'm going to call it a.

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I'm going to give it a value of seven.

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I'm going to create another variable and I'm going to call these B and I'm going to give it a family

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of eight so I want to use the if statement to check for setting conditions before I can run what's inside

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this file.

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So I'll see if a and then I'm going to use an operator to check I'm going to say if a is less than B

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and now add my call on the colon is very important.

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When I press Penta you can see is well indented indentation is very important in Python.

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So if you're using pi charm it should automatically indented for you.

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So now is prompting me to enter a new line of code.

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So I'm just going to say print and inside my print parentheses we just see the a variable comma there

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now our entire text.

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I would say is and then I do a comma to exit that string and then I'll say B B here is referring to

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the value of these variable B.

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So once I've done I just save my file.

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Now what this will do.

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Basically I'm using this operator here which is the less than sine to check for condition the condition

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I'm checking for is is the value of a variable a is a less than the variable B 7 which is the value

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of variable a is less than the value of variable B.

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So the condition is true.

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And then this block of code will execute.

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Now if the condition is false nothing happens.

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The code will not run it will just do nothing.

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So let me run this code so that you can see all right click and go play.

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You can see here is output at 7 which is the value of variable a is smaller than 8.

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Now if the condition was false nothing will happen.

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Say 5 reverses for example if I changed that to a greater than that will make the condition false because

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a which is 7 is not greater than B which is 8.

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So now let me try and run this again.

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You can see nothing runs you see the code does not execute this block here it does not execute.

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OK so what ever code you have inside the F block.

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This here.

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Well I put the print function is known as the F block so if the condition I set here is wrong or if

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it's false this code will not run the code will only run if the condition inside the F block is true

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or evaluates to true.

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So if statements are very important in your control flow always remember the indentation and the call

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on any way you see a colon here.

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You telling the interpreter that you want to start a new line of code and make sure it is indented.

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If it's not indented the code will not run.

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The interpreter will complain are set for this video on if statements.

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Thanks for watching and bye for.