| 00:08 | Welcome to the video component of the two. For this course here we're |
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| 00:17 | cover the very very basics of python switch to some slides. So the |
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| 00:30 | today is python basics. As we at the beginning of this course, |
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| 00:40 | is the language we are selected to instructions to a computer. So let's |
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| 00:47 | started with that. So today we'll what is what is the python program |
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| 00:54 | values and variables that are the real . The next thing is assignments and |
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| 01:02 | , and then we'll talk a little about input and output in python. |
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| 01:07 | very basics, so for writing a in python, we need to know |
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| 01:18 | few things that really don't have anything do with the language. But just |
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| 01:24 | reminder of some of the things we have already discussed. A python program |
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| 01:30 | plain text. Um it's not binary any such thing. Most real world |
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| 01:38 | programming is done in something called an development environment. So the idea is |
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| 01:45 | instead of writing a program in a file or something and trying to run |
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| 01:51 | , you get some assistance in developing program running it. And these things |
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| 01:57 | I. D. S. These slides and some examples of those for |
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| 02:03 | con include peachum and spider and several , but also the the book that |
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| 02:11 | using that has a Bill written python environment. So you can actually write |
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| 02:19 | run python programs in the book itself that is what we will primarily be |
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| 02:25 | in this course, at least for for the first couple of weeks. |
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| 02:29 | you don't have to go outside to a python environment, everything is there |
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| 02:35 | the room stone text that you So the um uh it allows, |
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| 02:47 | not a sophisticated so called I D but it does allow simple things like |
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| 02:51 | by step execution, which is helpful um um program in in understanding how |
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| 02:59 | program is running. So moving on few more basics just so that you |
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| 03:09 | , a python program will have the containing a python program will have these |
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| 03:17 | py in the end. So so know which one is a python program |
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| 03:22 | with something else? Um computer programs case sensitive. Just remember that uppercase |
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| 03:29 | is not the same as lowercase They mean could mean different things. |
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| 03:33 | finally outside of the main program you have comments that look like this. |
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| 03:39 | just for your visual clarity. Those comments, those are not part of |
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| 03:45 | core program. They're meant for human and another little detail you'll see |
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| 03:54 | we haven't told you where you need but you need courts. And in |
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| 03:58 | interestingly double court and single court mean same thing except that a single court |
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| 04:06 | to be matched with a single court a double court has to be matched |
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| 04:09 | a those are some little background I wanted to get out of the |
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| 04:14 | before we start talking about real So getting to the real stuff of |
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| 04:23 | , the first thing is very Something I call a value, values |
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| 04:30 | things like the number 14, the 3.9 the number of the string, |
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| 04:39 | , basically any quantity, an element python manipulates computes with creates and so |
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| 04:49 | is usually something that we say is value and you hear the term object |
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| 04:56 | value for now in python at least now just think of it at the |
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| 05:02 | whether somebody says an object or value matter. We are referring to something |
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| 05:08 | this for the number or string or like that. Every value has a |
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| 05:16 | , a data type. So this also a very accept but many words |
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| 05:24 | used to explain the same thing For . At least, data type is |
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| 05:30 | as type is same as what's called class. So they're all the same |
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| 05:36 | least for now, at least in score. So we don't want to |
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| 05:41 | into details that are irrelevant right Now, what are these types? |
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| 05:47 | there say the number 14 is an makes sense. 3.9 is a decimal |
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| 05:56 | and a decimal number is referred to a float and alpha is a string |
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| 06:03 | we're like technically it'll be str so n t f l O a t |
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| 06:07 | s d are the official terms we to um uh for for these um |
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| 06:16 | types. Okay, just gonna switch here. So once again this is |
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| 06:26 | a summary of what we have covered integer. What we think of as |
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| 06:31 | is python, type I. T. And examples of 1 23 |
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| 06:35 | 1 23 0. A real value five. And some examples of two |
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| 06:43 | something something. And you can also things like E to the power something |
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| 06:49 | such and strings are any text. enclosed between court marks. So here |
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| 06:56 | some examples of those. Let's move . Um python allows us to find |
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| 07:09 | type something else is and it might right now but it's still useful and |
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| 07:16 | will make more sense. So you know what the type of something |
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| 07:20 | Use this function called type. And with that function said tell me what |
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| 07:27 | something is. So here let's think this one at a time. When |
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| 07:33 | say type, What type is Clearly this is a string. So |
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| 07:39 | should return str look at 43. is we know it's an integer. |
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| 07:47 | It should return I. N. . Um 4.3 seems like a float |
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| 07:54 | uh real number which python calls it float. So that should be |
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| 08:01 | And uh the Let's look at It's 43 but it's enclosed in |
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| 08:11 | Anything enclosed in quotes is a So this should be string. It |
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| 08:17 | matter that the actual content of string like a number. So but don't |
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| 08:26 | my word for it. Go to python and profess in the book, |
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| 08:31 | these statements on and see what you get. And let me know if |
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| 08:35 | get something other than what's here. we'll talk a little bit about type |
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| 08:46 | . Sometimes it makes sense to switch one type to another. Okay, |
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| 08:53 | um now look at this statement So float is one of the you |
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| 09:04 | use, it's the same term that use for the type. You can |
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| 09:07 | use it as a function to convert to float something uh to convert to |
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| 09:14 | . So the number two, you to convert it to float two looks |
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| 09:20 | an integer. But of course you be a real value to. So |
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| 09:24 | you do this, you should get like 2.2 point zero. Is the |
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| 09:31 | or python's way of saying that I to but I'm thinking of it as |
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| 09:36 | real number or um not not as integer. Okay, Let's see. |
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| 09:45 | . Now it says in 2.9, is another of those that is a |
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| 09:52 | but it can be used as a to convert something to an integer. |
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| 09:58 | it's actually unclear what what does it to uh convert 2.92? An |
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| 10:08 | You could say that maybe you should at the closest integer to the |
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| 10:14 | That would be three. And but is an alternate where where you forget |
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| 10:20 | the fractional part and that's what python . So if you do this it |
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| 10:26 | it's when you can what it uh to an integer in python it forgets |
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| 10:32 | the part of the decimal so you get to Now here moving on, |
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| 10:41 | a a string and the content of string is 48, Converting that to |
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| 10:50 | integer intuitively makes sense because after all just a number, it just happens |
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| 10:55 | be in the strength form and that's Python does. The answer you'll get |
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| 11:00 | would be 48. No If we 4.8 into a string that's okay to |
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| 11:12 | string can be anything. You have float 4.8 and that can be converted |
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| 11:17 | a string. So intuitively thinking of as a string, that would be |
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| 11:24 | this. But actually when you print string, although when you enter a |
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| 11:30 | you have to put coats. When print a string um there are no |
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| 11:35 | . So actually when you print it get like this but just four |
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| 11:39 | But it's just printing it as a . Don't worry if that confuses you |
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| 11:43 | now but the basic idea is that float has been converted to a string |
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| 11:49 | then it has been printed. Now at this for a minute, there |
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| 11:55 | a string called number N u m R and you want to convert it |
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| 12:02 | an integer. This makes no You can't have a little string even |
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| 12:11 | it looks like you know something pneumatic its meaning to be converted to a |
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| 12:17 | . So this is meaningless, you get an error. So the story |
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| 12:24 | that these conversions only work when they sense. So that's the best way |
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| 12:30 | think of it right now. Instead you know detailed rules for everything, |
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| 12:34 | is where this statement comes from. now we'll just use common sense in |
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| 12:41 | out what can or cannot be converted within that common sense condition you can |
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| 12:50 | conversions between these types. Alright, so far we've looked at values, |
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| 13:05 | going to introduce Two of the most concepts in any language which is variables |
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| 13:15 | assignments um in the next couple of . So variable is a name that |
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| 13:23 | to a value. So we had 4.345 whatever instead of the actual |
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| 13:30 | we can give it a name and uh you can imagine that makes life |
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| 13:36 | in many ways. And the way variable is created is with an assignment |
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| 13:42 | . So a statement like this month it takes this value eight and assigns |
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| 13:50 | to variable month. Okay, It a value. Month is a |
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| 13:55 | Now, month is attached to it radius equals 5.0 the only difference is |
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| 14:01 | now the value is a flawed and says title equals introduced Python. Now |
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| 14:06 | value is strength, but essentially all these are variables and we can assign |
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| 14:15 | to them and by what's called an statement. Okay. Should be pretty |
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| 14:24 | . The way to think of Is that a variable is a |
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| 14:35 | So month radius title, they're all , anything can go inside them. |
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| 14:43 | ? And when we executed those assignment , this is what happened That those |
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| 14:52 | those empty box called month. It's filled with it. The box radius |
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| 14:58 | the value of 5.0 and the box has introduced Python. So it's it's |
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| 15:05 | to start thinking variables right way. and uh the the way to think |
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| 15:12 | be slightly different in different computer but this is the best way to |
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| 15:17 | in python. So, um remember you may have uh used or you |
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| 15:26 | have used variables. In algebra. always this X in algebra that you're |
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| 15:31 | to find the value of. They related but not the same concept. |
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| 15:37 | algebra variable is something that you don't the value of your trying to find |
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| 15:42 | value in python. It's a name you give to a value. |
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| 15:48 | so a valuable has a name. , just this is some basically housekeeping |
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| 15:58 | . What can be a variable, write the program and you name the |
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| 16:03 | in your program. Can any, know, any word be available more |
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| 16:10 | less. Yes. So variables are composed of uh letters. They can |
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| 16:16 | uppercase or lowercase. It'll be Something with an uppercase, something with |
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| 16:20 | lower case. They can have digits they can have underscore. So that |
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| 16:26 | that's what you have to use a of those two. Put together the |
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| 16:31 | of a variable with the condition that first character must be a letter. |
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| 16:39 | the first character cannot be a And technically the first character can be |
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| 16:48 | , but for this course you're strongly to not use to start all your |
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| 16:55 | with the latter not underscore because sometimes underscores has special meaning and it's not |
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| 17:02 | it to take that risk. So don't use them and you won't accidentally |
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| 17:06 | into trouble. So for for now character has to be a letter. |
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| 17:14 | only other condition is that there are words that have a special meaning in |
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| 17:21 | . You can imagine if else if and we don't know the meanings |
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| 17:26 | But you can imagine they probably have specific meanings and it would be very |
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| 17:32 | if you said if equals two. you're not you're not allowed to do |
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| 17:38 | . Um You can look in the the book, the list of these |
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| 17:44 | words and generally just get a rough of what it is. So that |
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| 17:49 | don't accidentally use them that's about So those are the rules of what |
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| 17:57 | allows you to do? Which is wide and but then there are the |
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| 18:02 | of what is a good idea. basically you want variable names to be |
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| 18:08 | and intuitive right? Because you want be to remember and be able to |
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| 18:15 | what is the significance what a valuable for. So if if you use |
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| 18:22 | tax, total cost then it's intuitively what it stands for. There was |
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| 18:27 | reason to call them these. As as python is concerned, you could |
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| 18:32 | said, you know the first one X. One. Second one is |
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| 18:35 | . To the third one is Three and python is happy but you |
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| 18:40 | be happy. And if you are with another person on your program they |
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| 18:46 | be happy because you know there's there's no useful information anymore in the |
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| 18:52 | of the variable settle. No. already talked about the assignment statement and |
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| 19:04 | said that a variable is created with assignment statement when we said something like |
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| 19:11 | equals for prices. The variable name the price equals for is the assignment |
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| 19:18 | . So those who are actually special of an assignment statement in general. |
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| 19:25 | assignment statement has a variable name on left hand side and an expression on |
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| 19:32 | right hand side. These are examples uh general assignment statements um There's a |
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| 19:41 | on one side and a bunch of that are being uh kind of processed |
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| 19:50 | the other side. Okay. Um what does what does python do when |
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| 19:58 | sees a statement like that? First it does is evaluate the expression on |
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| 20:04 | right. Forget about what's on the in this area, you evaluate |
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| 20:10 | so you multiply by 3.14 by five five and see whatever value you come |
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| 20:16 | with and then once you are you store the resulting value in the |
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| 20:23 | name on the left. So now area gets this value whatever. 55 |
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| 20:28 | 3 75 something that gets that So it's a two step process compute |
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| 20:34 | expression on the right. What our . It computes to store the results |
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| 20:39 | the on the in the variable on left. Okay. Um yeah. |
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| 20:49 | if you already noticed that the expression the right can have values, it |
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| 20:55 | also have other variables. And if the case, whatever is the value |
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| 21:00 | that variable at that point would be for computing the expression. So a |
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| 21:09 | bit more on Expression for the next minutes, expressions consists of two |
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| 21:18 | operators and operations. So operators are that uh manipulations or how what what |
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| 21:32 | used to make computations. Things like , subtraction, multiplication, division. |
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| 21:38 | all operators and operations is what you those to. These are numbers |
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| 21:46 | other valuables and and stuff. so let's look at an example it |
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| 21:52 | 45 plus nine. Now plus this the operator, some is the operator |
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| 22:01 | nine and 45. Our operations here have the expression two multiplied by |
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| 22:09 | multiplied by r. The multiplication are operators And two and Pi and R |
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| 22:21 | the operations. Okay. So same you have area slash 2.0 areas and |
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| 22:28 | . And to point out as an and slash or division is the |
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| 22:32 | And here you've got this operator which multiplication, that acts on two sub |
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| 22:42 | which themselves have operator minus here and here and the operations are A and |
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| 22:49 | and a and four here. So is this is nothing just we want |
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| 22:56 | make sure we have a vocabulary You've seen enough of that in your |
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| 23:01 | courses. Um Most of the operators python of intuitive multiplication is multiplication, |
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| 23:12 | , is addition, subtraction, Uh There is some issue with division |
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| 23:19 | the division takes multiple forms. The slash is decimal division. So if |
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| 23:26 | decide 30 by eight you get 3.75 you calculate hopefully that is correct. |
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| 23:34 | , um there is also the concept integer division, integral division means you |
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| 23:41 | 30 by eight and you only the is the caution without the decimal |
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| 23:50 | So that one is uh the the for that is double slash. So |
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| 23:56 | how you distinguish real multiplication and integer . And finally if you may also |
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| 24:08 | you have the quotient and the remainder um integer division. If you want |
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| 24:14 | remainder, you use this percentage sign your operator. So you You're looking |
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| 24:21 | remember when you divide 11 x three you calculate remember should be too and |
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| 24:27 | what it returns. So this kind completes the list of basic operation. |
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| 24:32 | are into their plus minus multiplication and on. Okay. Uh so um |
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| 24:47 | , once you have a bunch of and operators, what is the order |
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| 24:54 | which they should be calculated? For you have a plus B multiplied by |
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| 25:01 | . Do you do the multiplication first added to the multiply B plus |
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| 25:09 | b n C and added to Or you add a plus B and |
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| 25:13 | multiply to see, you can see these will return very different answers. |
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| 25:22 | python follows what is well known mathematical , you should already be aware of |
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| 25:29 | and you can you know, check anywhere which just means cost, you |
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| 25:34 | exponential pension and negation. Next is and division next to the addition and |
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| 25:41 | . And when everything is the you have a bunch of addition and |
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| 25:46 | . You don't know because they all the same priority. You go left |
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| 25:50 | right except exponentially ation. You go other way. These are the rules |
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| 25:56 | you you're probably familiar with them So now based on these rules, |
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| 26:03 | plus B multiplied by C. Is this with parenthesis. With be multiplication |
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| 26:11 | see happening first and that is represented the parenthesis. And here you have |
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| 26:19 | exponentially ation. So the exponentially ation first and then the multiplication and then |
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| 26:26 | . Now note that both these statements the left and right are legal python |
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| 26:34 | . So one is uh they're equally as far as python is concerned but |
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| 26:44 | always a good idea to write python like this so you don't have to |
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| 26:50 | and remember all the President's rules and if the even if your intended to |
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| 26:57 | the president's you're still free to put corinth Asus and then it's clear what |
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| 27:03 | of operations you intend in your So that's um that's about it for |
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| 27:15 | presidents and in general expressions I wanted put a few more examples of string |
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| 27:24 | type because that's something which we're not to as much in mathematics. So |
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| 27:30 | python strings are any characters between between quotation March, Right. So my |
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| 27:40 | is a string. Another string example another string. The and there are |
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| 27:45 | blanks count. They're part of the to just to get more familiar. |
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| 27:52 | can have strength. That is A C lower case abc uppercase and blank |
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| 27:59 | blank C. But they are all different strengths. Small, lower case |
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| 28:05 | . And upper case. Er just characters that have nothing to do with |
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| 28:09 | other And space is also a These two are different because upper and |
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| 28:16 | is different. These two are different there are spaces and uh you can |
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| 28:22 | letters, digits, special characters. everything within a string and it doesn't |
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| 28:29 | . It's just uh carried whatever way looks, they don't have it within |
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| 28:35 | string concept. They don't have any meaning. It's just everything is a |
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| 28:39 | whether it's a letter or a digit and some special characters. So wrapping |
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| 28:51 | with pipes, if you can think her type as a set of values |
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| 29:00 | a set of operations that you can on them. So we've talked about |
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| 29:06 | float and string as the type so . So here are some examples of |
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| 29:11 | there's an infinite list of integers and of these but these are the set |
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| 29:17 | values that can be integer plus minus uh anything between you know plus and |
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| 29:24 | infinity. Uh These are examples of these are examples of strength. So |
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| 29:31 | aspect of a type is what values be that type and I think looking |
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| 29:36 | this, it should be intuitively clear the second component is of a type |
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| 29:42 | what operations you can perform on Okay, so we've seen most of |
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| 29:49 | , we know most of these intuitively integers. The operations we can perform |
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| 29:55 | addition, subtraction, multiplication, Uh that we can do real type |
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| 30:03 | , integer type divisions. You can um you know very minor. That |
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| 30:07 | just means you can say minus four percent we saw is a remainder and |
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| 30:13 | is exponential station. This is intuitive floor is the same except for things |
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| 30:20 | don't make any sense which would be doesn't make any sense. Integer division |
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| 30:26 | make any sense in a float. those are not allowed. And finally |
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| 30:32 | also have some operations on them that represented by plus sign and start the |
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| 30:39 | sign. It is not obvious what what they should mean. So python |
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| 30:47 | made an adult decision that a plus strength and concatenation. So A B |
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| 30:54 | plus C. D. That those are strength is just A B c |
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| 30:59 | D E. And multiplication is duplicating strength. So if you say two |
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| 31:07 | by string A B, you'll get B A B. And that's about |
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| 31:15 | the operations you can do on these Again, types means a set of |
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| 31:22 | and what operations you can do on . And this table pretty much covers |
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| 31:28 | uh you know, that define completes definition of a type or the types |
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| 31:34 | we will be interested in. So some situation python will has to decide |
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| 31:52 | type of a result. For Here you're dividing one by 21 is |
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| 32:01 | integer. Two is an integer now the symbol you're using is real |
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| 32:11 | So python here does what Common sense it returns the value of .5 which |
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| 32:21 | course is a float. So you get you do it this kind of |
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| 32:26 | conversion or you see this kind of conversion when you're calculating an expression. |
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| 32:33 | result is a flirt even though the operations oriented now look at this one |
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| 32:43 | a second. So the X value the same as 10.5 point five is |
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| 32:50 | by two. So the value will one. But the question is is |
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| 32:56 | now afloat or an integer python says a float. So in general when |
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| 33:05 | have an operation between an integer and floor. The result is a |
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| 33:09 | So yeah this is just just something know and most of the time this |
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| 33:17 | intuitively what you would expect. So to variables assignments and that we already |
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| 33:29 | and a variable can be assigned different at different points in a program. |
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| 33:37 | in the discussion so far we gave variable one value and didn't didn't worry |
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| 33:42 | it after here this is a perfectly uh cord the you say I. |
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| 33:51 | . Equals court. Do not know . Just ignores like difference between the |
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| 33:57 | and end court and then you say . D equal Susan then you say |
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| 34:01 | . D. Equals 47 nor that is an interesting. Okay so this |
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| 34:06 | perfectly legal. Remember a variable is container, you can put one thing |
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| 34:12 | then you can throw that out and can put different thing and then you |
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| 34:15 | throw it out and put a different . So the way to think of |
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| 34:20 | happens here is that after the first you have um this situation here you |
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| 34:30 | the variable I. D. Remember . D. Is a container. |
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| 34:33 | the container has the strength. Do know yet. Right? So and |
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| 34:39 | you go and execute the statement saying . D. Equal Susan at that |
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| 34:45 | . This connection is broken I. . Does not stand for, do |
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| 34:50 | know yet anymore. Now it is to this value Susan. So |
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| 34:56 | D. Is now Susan and when say I. D. Equals |
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| 35:01 | Once again this connection is broken and this point the I. D. |
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| 35:07 | variable I. D. Has a content in it. 47. |
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| 35:13 | So uh basically a variable is a . You can take one thing out |
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| 35:18 | put a new thing in and the you do it is with repeated assignment |
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| 35:24 | with the same variable on the left side. Hopefully this is clear. |
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| 35:31 | also I think this is really intuitive of course multiple variables can have the |
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| 35:39 | value. So you can have item equals 4.5. Total price equals 4.5 |
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| 35:45 | something else. And uh one way think of it is when you said |
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| 35:52 | price you got the value 4.5. uh the total price can also be |
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| 36:02 | the same and you can think of um as another variable but that has |
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| 36:10 | same content in its uh it's containing same value of pointing to the same |
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| 36:29 | . Okay um A minute on a very common pattern of reassigning a variable |
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| 36:40 | python in any other language. Is one? Count equals count plus |
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| 36:46 | Okay now if this was algebra this not make any sense. Right count |
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| 36:51 | available. Is that it cannot be count and countless one cannot be equal |
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| 36:59 | this equal is not really equal in ? It's uh it's an assignment statement |
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| 37:06 | ? So now what happens here is what we expect if we follow the |
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| 37:14 | of executing an assignment statement? So we said the rules of the |
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| 37:20 | just say account was 10 before the was executed. Said there was count |
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| 37:27 | stand before it. The rules for or evaluating an assignment, Our first |
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| 37:36 | the right hand side. So when evaluate the right hand side is count |
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| 37:40 | one. So this is gonna be plus one equals 11. After |
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| 37:45 | once this is complete, you say the value to the variable name on |
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| 37:50 | left. Now the valuable count becomes . Yeah so the end result of |
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| 38:00 | county calls count plus one. Is the value of count would be one |
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| 38:05 | than before. Um So if it 10, it will be 11, |
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| 38:09 | was 100 will be one on one so on. So it's perfectly |
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| 38:13 | perfectly legitimate python statement which is extremely . And as we said, this |
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| 38:20 | another way to think about how variables algebra and programming languages are different. |
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| 38:29 | makes no sense in algebra, but a good common way of using variables |
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| 38:36 | assignments in python. So just a more minutes using the not using, |
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| 38:49 | about input and output. How do get data in into a python program |
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| 38:54 | computation? How do you throw it ? Um And we're not gonna cover |
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| 39:04 | possible way that python can get input create output but just enough that uh |
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| 39:12 | can get started. So python has built in function called input. So |
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| 39:19 | happens when you say input and python running a program? Uh This is |
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| 39:27 | input from the keyboard. Everything stops you can't move forward until we've got |
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| 39:36 | import from the user. So the is given a prompt saying that you |
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| 39:44 | to enter some input here and when user presses returns or enters the import |
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| 39:49 | says okay I have my input Here's the input. Let's start |
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| 39:53 | The program resumes and keeps going and the user enters is considered a |
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| 40:01 | So I think this will become more in the next minute or so. |
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| 40:07 | if you had um this statement um , what is your name? It |
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| 40:16 | two components. One is that this you have in this string is uh |
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| 40:25 | uh part of the prompt. So got printed on the on the user |
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| 40:30 | so they know that you're looking for name. So if you are a |
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| 40:35 | you will see this, what's your ? So let's say the user entered |
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| 40:39 | genius here and let's so then at point the name gets the value the |
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| 40:49 | , clever genius. So if you print name after that clever genius will |
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| 40:53 | printed. Okay, so it's very . You say import. When you |
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| 40:59 | import you can put any string in and that will get presented to the |
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| 41:04 | who's giving the import and whatever input user gives. That will be the |
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| 41:12 | of the variable here as a So now the that begs the question |
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| 41:23 | if you actually want an integer or if you actually want somebody to enter |
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| 41:28 | float? Because your program you is looking for say the you know |
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| 41:34 | length of a table and that is float in python um types um you |
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| 41:45 | enter the import as a strength. you will have this statement, you |
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| 41:52 | G P A equals flowed input. is so the import statement is still |
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| 41:59 | similar. Okay. And what comes is a strength. So when somebody |
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| 42:06 | 3.9 then that is comes in as string. But this function float, |
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| 42:13 | it to a float. And then you type after that the type is |
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| 42:18 | . This is Python's way of saying . It is, it is |
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| 42:22 | Okay, so basically all input has be entered as a string but that's |
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| 42:29 | a serious limitation. You can enter integer, read it as a string |
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| 42:34 | convert it to an integer. Similar float. You have inter type conversion |
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| 42:39 | you get an integer or you take as a string and convert it to |
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| 42:44 | float. If you don't do it will stay as a strength. |
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| 42:47 | is important to remember, especially for programmers, sometimes you forget you think |
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| 42:53 | I'm going to enter too and it be a number but if you don't |
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| 42:58 | it to an integer, you try say divide by two and you'll get |
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| 43:03 | error because you cannot divide by uh your strength. So this is a |
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| 43:10 | detail. That's good to remember. for output we are only going to |
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| 43:17 | the print function which we've already used times just in this lecture is just |
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| 43:24 | , whatever. The only thing we're to add here is so far everything |
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| 43:30 | like print and then there was value variable. In reality you can have |
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| 43:37 | values. For example, this is legitimate print statement. It has first |
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| 43:45 | is a string. There are then . There's a comma. Then there's |
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| 43:50 | second value. 34 multiplied by Then there's a comma and then there's |
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| 43:55 | third value which is another string which um seconds and 34 minutes. And |
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| 44:04 | the the final uh chancellor is that's , is there 2040 seconds and 34 |
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| 44:15 | . So that makes it easier to out when you're when you're trying to |
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| 44:20 | out something meaningful that includes multiple You can print in one shot versus |
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| 44:26 | multiple prints treatments. So this is Oh yeah, so another thing is |
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| 44:39 | variables and expressions which is implicit when say 34 multiplied by 60 as you've |
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| 44:46 | here. It is calculated before being . So you don't print 34 and |
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| 44:54 | multiplication than than 60. It's an . So the whole expression is evaluated |
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| 45:00 | you saw and it's 2040. However in In this case seconds in 34 |
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| 45:08 | everything was a string. There was computation. So it got printed as |
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| 45:16 | so this is the end of the summary is once again, we are |
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| 45:24 | into computer programs, a computer program an implementation of an algorithm and um |
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| 45:34 | talked about variables, variables, world that can be accessed by our |
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| 45:39 | we have assignment statements that assign values variable and we have numerical data that |
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| 45:46 | be represented in python using in and data types and uh our text is |
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| 45:54 | , string data type and there are basic um input and output functions. |
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| 46:02 | , that is the end of this lecture. Um and uh we will |
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| 46:11 | you in class soon. |
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