WEBVTT 00:00.080 --> 00:02.600 Hello developers, and welcome back. 00:02.640 --> 00:05.120 Let's start diving into Python. 00:05.240 --> 00:13.520 And in this course we're going to learn the basics and the part of Python that it is required for machine 00:13.520 --> 00:14.240 learning. 00:14.440 --> 00:17.000 Python is a popular programming language. 00:17.200 --> 00:22.640 It was created by Van Rossum and released in 1991. 00:22.840 --> 00:30.520 It's used for web development, server side software development, mathematics system scripting, and 00:30.520 --> 00:32.120 machine learning. 00:32.320 --> 00:40.280 Python works on different platforms windows, Mac, Linux, Raspberry Pi, and etc. Python has a simple 00:40.280 --> 00:42.520 syntax similar to the English language. 00:42.720 --> 00:50.840 Python has syntax that allows developers to write programs with fewer lines than some other programming 00:50.840 --> 00:51.680 languages. 00:51.960 --> 01:00.990 Python runs on an interpreter system, meaning that code can be executed as soon as it is written. 01:01.030 --> 01:04.230 This means that prototyping can be very quick. 01:04.430 --> 01:11.790 Python can be treated in a procedural way, an object oriented way, or a functional way. 01:11.950 --> 01:19.710 We are going to use Python for the machine learning, so there is no need to install anything on your 01:19.710 --> 01:20.550 computer. 01:20.590 --> 01:26.910 As I told you, go to Colab, sign up or sign in with your account. 01:27.110 --> 01:35.870 Click Open Colab, import the file, upload the notebook and upload the notebooks that I provided in 01:35.910 --> 01:37.910 the resources folder below. 01:38.030 --> 01:43.350 Okay, later we're going to upload many files, so please pay attention. 01:43.350 --> 01:45.950 Download them from the resources folder. 01:45.950 --> 01:47.550 They are very simple. 01:47.670 --> 01:51.030 Click upload and you will get this file. 01:51.030 --> 01:57.390 This notebook will guide you through the fundamentals of Python programming starting from the very basic 01:57.540 --> 01:58.580 variables. 01:58.780 --> 02:00.020 Data types. 02:00.020 --> 02:00.860 Operators. 02:00.860 --> 02:02.780 Basic input output. 02:02.820 --> 02:03.340 Okay. 02:03.580 --> 02:07.220 So you can create text or cells. 02:07.340 --> 02:09.220 Let's start coding. 02:09.380 --> 02:13.620 The first thing we need to learn is creating variable. 02:13.620 --> 02:21.620 In Python, a variable is a name that refers to a value stored in the computer's memory. 02:21.780 --> 02:27.940 You can create a variable by assigning a value using the equals sign. 02:28.140 --> 02:36.980 For example, name Alice, age 25, height 5.9 and is a student is true. 02:37.020 --> 02:40.820 Variables are containers for storing data types. 02:40.860 --> 02:44.260 Python has no command for declaring a variable. 02:44.460 --> 02:49.460 A variable is created the moment you first assign a value to it. 02:49.580 --> 02:53.060 For example, here we created a variable called name. 02:53.060 --> 02:58.040 It's of type string a variable age of type int. 02:58.120 --> 03:04.920 A height variable of type decimal is a student is a variable of type boolean. 03:05.240 --> 03:07.960 So you can print those variables. 03:07.960 --> 03:11.840 Variables don't need to be declared with any particular type. 03:11.840 --> 03:16.880 You can even change type after they have been set by using casting. 03:16.880 --> 03:22.760 But we are uh, we are interested in this single thing. 03:22.920 --> 03:28.320 In order to print them, we can use the print function. 03:28.320 --> 03:36.480 So if I click on this run cell icon we get this output Alice 25 5.9. 03:36.480 --> 03:37.320 And true. 03:37.400 --> 03:40.720 Those lines are not executed. 03:40.760 --> 03:44.480 Those in green because they are start they are comments. 03:44.480 --> 03:50.320 And starting with this sign comments can be used to explain code. 03:50.320 --> 03:55.470 So here we are explaining that we are going to create an example for creating variables. 03:55.470 --> 03:57.990 And here let's print them. 03:58.110 --> 04:04.550 Comments can be used to make the code more readable, and comments can be used to prevent execution 04:04.550 --> 04:05.710 when testing code. 04:05.710 --> 04:11.350 So when running the code, those lines, those comments are not executed. 04:11.350 --> 04:13.550 So comments start with this sign. 04:13.550 --> 04:17.510 This hash tag and Python will ignore them. 04:17.550 --> 04:27.870 A variable can have a short name like x and y or more descriptive name like age, height, name is student 04:27.870 --> 04:28.830 and others. 04:28.830 --> 04:31.790 But there are some rules for Python variables. 04:31.830 --> 04:37.390 A variable name must start with a letter or the underscore character. 04:37.430 --> 04:43.470 A variable name can't start with a number, so I can't put like this five h. 04:43.670 --> 04:45.390 It will give me an error. 04:45.550 --> 04:51.990 A variable name can only contain alphanumeric characters and underscores. 04:52.190 --> 04:53.060 So here. 04:53.100 --> 04:53.740 Age. 04:53.860 --> 04:57.100 For example, I can make like this. 04:57.140 --> 04:57.980 It's good. 04:58.020 --> 04:58.540 Okay. 04:58.740 --> 05:04.620 But we can't replace numbers at the beginning of the name of the variable. 05:04.820 --> 05:07.100 Variable names are case sensitive. 05:07.100 --> 05:11.700 So age is different from this age variable. 05:11.940 --> 05:12.540 Okay. 05:12.780 --> 05:21.100 So this age is different from this age a variable name can't be any of the Python keywords. 05:21.220 --> 05:30.340 For example uh, the Python keywords uh def I can't create a variable named def for example 66. 05:30.420 --> 05:33.660 Uh I can't create a variable called for. 05:33.860 --> 05:35.380 This is for the for loop. 05:35.580 --> 05:37.860 Those are reserved keywords. 05:38.060 --> 05:46.700 I can't create f or I can't create else or any other variable or any other function. 05:46.700 --> 05:52.020 In Python those are reserved the reserved keywords in Python.