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Hello.

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Welcome back.

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So in this lesson we going to look at some operators available to us in python.

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This is our last project.

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We ended over here with list.

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We're going to create a new script from this one.

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I'll click file new file and then a press control as to save and I'll name this number three and I'll

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call this operators like this now.

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And once that is done I can close this one too right.

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So we have the basic operators available to us such as multiplication addition subtraction and division.

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So let's say we want to add a number we can say equals one plus two.

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And indeed we know what the answer is but let's just print and see if indeed it behaves the same way.

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So we can print and control as I've come over here run module and what we have is num indeed equals

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three and in the same way we can come down here and say num because num asterisk 2.

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And just like in other languages the asterisk sign over here is for more application of control as click

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here to run run module.

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And indeed I'm not printing the NUM so I'm just going to come down here.

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Cut the print statement and bring it down here and let's see what we get.

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Control is run module and indeed three times to six.

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So we've got six printed and we can do a module or sign as well we can see a remainder Yeah we can say

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remainder equals 10 percentage for let's say we want to print the answer print remainder and we can

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hash this one out by commenting it out you can run this save and this indeed is to the remainder of

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10 which looks for is two.

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So one other way one at a trick I'll show you a nice way to concatenate this there are two ways to concatenate

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an integer with a string right integers for instance four plus four plus forty six eight.

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But how about four plus.

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Boy what would it give us course we shortened out by saying Good plus afternoon equals good afternoon

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and four plus four.

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Of course eight.

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What happens when we see a four plus boy.

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Right.

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You've got a number and then you've got a string.

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How does Python deal with that since Python is so smart.

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You do need to declare your own variable is what happens when we throw such a confusion.

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How do we run the experiment and see what we get.

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So in this print statement I'm going to add an actual string kerosene remainder I'll call this string

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remainder like this and then I'll say remainder plus this.

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Yes see this is a very innocent thing to do.

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I'll click over here to run and on Arrow is thrown.

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Why I say it says can only concatenate string to string not integer.

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Very smart python.

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So in a solution to this is we know this is a number but we can cost this number to a string and we

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do that using the s t r function so I can come here and see SDR and then close here as well Contro s

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and then run and then now we have remained to we can put an equal sign here for those a few there who

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like things been done perfectly report on equal sine and then we run this then we have remainder of

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course two.

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So this is how we've just written a sentence very simply by in the integer to a string.

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Very simple very straightforward.

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So now let's see how to do exponents.

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How about a power to.

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How do we write apart too regularly.

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One would say square squared equals let's say twelve like this.

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This is what works in other languages but that's not the case or does that's not a case in Python for

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race that apart to all we have to do is asterisk austerity to let's say let's print squared and see

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what we get.

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And we know twelfth race the path to twelve squared is one hundred and forty four we know that.

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So we just print and see if indeed that is the answer.

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Let's hash this out to avoid confusion in the print so we observe and just this once that is done I

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just click over here run mode run module and then okay.

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And indeed it's one forty four.

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So this is how to do a race that part to hobble race to the path we then of course two becomes three.

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But let's try that.

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I'll say cubed equals twelve asterisk asterisk three and we can print cubed here print cubed

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and we can hash this out and then control s and click here to run the module and of course this is one

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thousand seven hundred and twenty eight and indeed twelve to that part three is one thousand seven hundred

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and twenty eight.

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So this is it.

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So in the same way if you want to raise the bar for two or four is the part twelve it becomes asterisk

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asterisk and then the particular number.

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So very simple.

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Now let's play a bit with list Hubbell list.

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Can we use these same operators with data structures such as list.

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How about we do that and see what we get.

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Let's say we have list one here.

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Let's declare list one we can see a list one of course one comma to call my three come off for comma

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five.

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And we can see a list to cause six.

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Call my seven comma eight.

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Come on nine.

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Come on ten.

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Right.

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Unless a complete list on this call list e course list one plus list two unless unless would come down

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here is a print Complete list complete on this call list like this Let's hush our last print statements

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out so that we observe just this resort.

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Yeah I put a harsh sign her control s run module and let's see.

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Right.

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This is how it's done it's actually concatenated it.

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So when we add to list in this format what happens is we increase the number of columns not a number

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of rows.

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This is like a matlab column addition.

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So what happened is the list.

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So list 1 has five columns.

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List two has five columns.

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When we add Alice want to list two we end up with a list of 10 columns.

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So that's how it behaves right.

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So let's see other ways that we can print numbers and strings together.

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Let's see this simple hash this out.

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Let's see the simple print example which is very common as well.

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We can see print come down here print

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something as simple as.

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Number is and I can just put comma to here like this.

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And see what it says.

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And indeed we have the numbers to write.

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You might wonder what happened with this.

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Well this was from an integer variable we could actually use this we could use the same method so we

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could have rather than type cast remainder to a string.

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We could have DSA to call my remainder Okay let's do that now.

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The number comma remained like this.

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S to save then I'm going to run module and indeed the number remainder is to do so from index to so

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don't be confused.

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So indeed this is one method of I didn't strings and integers let's let's test out some float.

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We've not done any float so let's say a mount

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amounts of course zero point seventy five like this and let's come down here and try to print amounts

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I can say print into bracket and over here you can see the amount is and then comma amounts and we expect

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it to work the same way.

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Let's hash this out.

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Control is to save and then click.

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Click here to run and indeed assess the amount as real point seven five.

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So another way of you know I didn't strings and integers is by using the percentage the percentage f

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for floats just like we do in C language.

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So let's say I come down here and see second amount equals zero point zero zero zero eight nine.

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Yeah very random.

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We can come here and say print cost.

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What will happen is this.

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This is this is easy to amount to the end of the sentence.

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But what if you want to add a number some way in the middle of the sentence.

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Yeah.

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The system games you.

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There's no way you can do that using this method to the actual way to do it is to use the same method

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used in languages like C and let's see what I mean.

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So why here.

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This is the amount so we can see string like this the amount percentage def is very very small.

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And what we have to do this time we don't need a comma or we need this D percentage sign.

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And then the name of the variable second amount is very important.

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Don't put a comma here.

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If you put a comma on Ariel be thrown.

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So you keep this the amount percentage F is very very small and outside of the string we have this percentage

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variable name.

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So control is to save or hash this old one out.

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This good example we did construe as to save click by here run module and it says the amount who appoints

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researcher 1 is very very small indeed.

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So let's see what I meant by pi mistakenly put in a coma.

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I put a call my hair.

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Let's see.

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In C language we do need to call my hair right by Python.

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We don't.

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So let's try this.

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You know this area and see if indeed it was an error or price controls to save.

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Click over here run run module and it says invalid syntax.

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And indeed the syntax is invalid.

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So I need to clean a comma contra s to save.

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Click run and then run module and then indeed the amounts you appoint Sure sure sure sure.

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One is very very small.

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So this it for this very somewhat long lesson on operators.

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I hope you understand is very simple python is very simple it just takes you know getting used to it

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like most languages actually.

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So if you have a question as a tool just send me a message or leave it in the questions area and.

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Yeah.

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And if you find the course useful please do take some time off to leave a review.

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Maybe if I'm moving too fast if that's an issue as well you can send me a message and I can reshoot

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some of the video was taken slower.

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So this weather is and I shall see you in the next lesson and have a good day.