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Hi, everybody, and welcome.

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This is a bonus lecture to the last lectures that we've dealt with variables and that this lecture we

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will talk about casting.

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So we basically learned what casting is without knowing it in the last lecture.

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We have, for example, this command right here.

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And we converted this number, which is a float because it has two numbers after that, similar as we

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talked in the last.

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So we converted it into a string.

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So this action is casting.

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When you put a variable inside brackets and outside, you type in the you type in the type of the variable.

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So basically you cast it because it is one type.

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This is the first type.

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And then you cast it into a different type, which is a string.

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So, all right.

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So Python is an object oriented language, as you all know.

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And as such, it uses classes to define it, to define data types, including its primitive types,

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which are string, integer and variable.

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So in this lecture, we'll talk about casting, by the way, the new class Biton file.

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Call it casting like variable casting.

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And

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and first of all, let's just enter into action and say here, casting from integer to string, which

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we already know how to do, and let's declare a integer variable.

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And that's said that is five and then let's do the following thing, let's do our string variable,

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you know what, integer?

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In Dejour, variable casted to string and what we want to do here, as Samia's we've seen a few seconds

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ago right here, let's put a SDR in brackets and put the variable string variable inside.

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So SDR recants and put the integer variable.

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Right here.

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So basically, if we have the integer variable here and we have the SDR casting action above it, so

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this variable should be good, you guess what type is this one?

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Let's try it.

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Let's just print it.

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But if we just copy this variable and place it right here, we are obviously going to see the simple

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value of it.

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So we're going to see five, right?

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So

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it's just five.

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We can see the type of it.

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But if you put the key word type outside of it and cover it with brackets like this, so everything

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that I'm marked right here is inside of the type, right.

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Sorry, inside the print.

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So all of this, we want to print it and now let's see what we want to print.

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We have the variable right here, which is an integer type variable with a value of five.

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And we have set the keywords a type outside of it.

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So basically what we want to print is as we want to print and the type of the variable.

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All right.

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That special word in Python and let's run it

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right.

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Amazing.

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So we can see the type of the variable here.

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So the integer variable cast it to string the casting was successful.

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And we can see it right here because we got the string type.

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All right.

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So let's do another example.

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We can do another print here with.

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Like, just for us to know, you know what, let's live it like this, so when you won't get confused.

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Right.

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So that's another point here and with quotation marks and put some stars just to differentiate what

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we get in the blogosphere.

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All right.

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So let's do another print.

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All right.

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And right here, casting from an integer.

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To float, so again, let's, uh, let's we have actually we have this integer variable, so let's just

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use it and.

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All right, so we're focusing on this one.

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This is our base variable that we going to cast now.

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So let's do the following thing, same as we did here.

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Let's create an integer variable.

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All right, let's button on the score here, integer variable casted.

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To float and now let's let's dive the key word, float the brackets and let's copied and pasted here.

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And now what we want to do is to print the type.

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That's the type of this variable, right?

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This is the new one we've done the casting right here and here is the new variable.

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So let's copy it and place it inside that the type brackets.

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And right, click on the file and run, you guys are so casting from integer to flow, so this variable

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is a float as we want it and let's do another one.

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Just copy the stars.

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Place sits right here and now we want to do casting from.

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From float to integer.

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All right, so we have here.

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All right, this one, this guy right here.

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We know it's a float, right, we have it's a float, so let's do casting on top of casting.

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All right, so let's bring this guy right here, which is a float back to being integer.

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So I'll just copy this one.

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And create a variable called float.

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Very able cast to.

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Integer and displays it and then put it outside like that.

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And so this one is a casting for the float variable.

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Copy this one copied and then again print.

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Type records and then based it right here.

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So we pasted this one inside the type inside the print run at.

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All right, great, guys.

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So now we know how to change one variable into another.

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So as you can see, Python is a very dynamic language.

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So you can get us the flexibility that we want and the code.

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And let me show you just one last thing.

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Let's try to print this integer variable and then let's try to print this integer variable cast to float.

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Let's print their values.

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All right.

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So I'm just going to copy it.

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And then print and then based it.

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And I still do the same as here, here.

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Brent, let's copy this white sorry, copy this one and based it right here.

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And let's run it, so all right, so as you can see, guys here, we have a string variable.

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Well.

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Well, well, sorry about that.

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Oh, yeah, it's OK.

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So here we printed the integer variable.

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All right, this is the integer.

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Yep, so the values five, and then we printed here the integer variable cast to float.

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So this one is a float.

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So you see that after we cast it it from integer to float, it has a decimal point and we can just verify

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that indeed we have a float here, as we can see a decimal point.

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That's about it, guys.

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So now you know how to do casting.

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And this is a great ability and great power for the role for test cases that we going to write, and

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that's about it.

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So it's not very difficult, but it's a really useful tool.

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All right.

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See you in the next lecture.