3. Numbers [Python 3 Programming Tutorials]

Summary

Highlights

• Use Python like a calculator to perform various mathematical tasks effortlessly. 🔢
• Employ stars (**) for exponentiation, such as 3**2 to yield 9! ⭐
• Distinguish integers and floats; integers lack decimal parts, while floats don them, making them versatile. ⚖️
• Master operation precedence: Just like math class, Python honors multiplication and division over addition and subtraction unless clamped in brackets. 🎓
• Discover the quirks of floats and rounding: a 6-5.7 might not give you 0.3, but rounding comes to the rescue! 🔄
• Harness variables for storing and calculating distances, like your epic drive from New York to Pittsburgh. 🚗
• Compute travel time on your terms by taking miles per hour and total distance into account. ⏱

Key Takeaways

• Python can act as a calculator for basic mathematical operations like addition, subtraction, division, and multiplication. 🧮
• To calculate powers in Python, use the '**' operator! For example, '3**2' equals 9. 🔢
• Remember, Python's math operations have precedence; use parentheses to control it! 🏗
• Rounding in Python is easy with the 'round()' function, perfect for controlling decimal precision. 🎯
• Integers vs. floats: integers are whole numbers, while floats have decimals. Keep them straight! 🌊
• Floating-point precision can be tricky due to binary storage, so 'round()' helps keep numbers neat. 💡
• Variables help store numerical data, making calculations and manipulations convenient. 📊

Overview

Chapters

• 00:00 - 00:30: Introduction to Numbers in Python The chapter introduces the importance of numbers in Python, emphasizing that numbers are an integral part of any software program. It states that Python can be used as a calculator, and demonstrates simple mathematical operations, such as addition, to show how numbers are handled in Python programming.
• 00:30 - 02:00: Basic Arithmetic Operations This chapter explains basic arithmetic operations including addition, subtraction, multiplication, division, and finding remainders. Symbols and signs used for each operation are discussed, such as the plus sign for addition, the minus sign for subtraction, the asterisk (*) for multiplication, the forward slash (/) for division, and the percentage sign (%) for finding remainders.
• 02:00 - 03:00: Creating Variables for Distances This chapter explains how to perform basic mathematical operations using programming. It covers how to divide numbers and find remainders using the percentage sign. For example, 11 divided by 2 gives a quotient of 5 and a remainder of 1. Additionally, the chapter introduces calculating the power of a number, such as finding 3 raised to the power of 2.
• 03:00 - 04:30: Calculating Travel Time The chapter 'Calculating Travel Time' includes mathematical operations like exponentiation, demonstrated with examples such as 3 to the power of 2 resulting in 9, and 2 to the power of 4 resulting in 16. It hints at broader number manipulation concepts relevant to Python programming.
• 04:30 - 05:30: Rounding Numbers The chapter discusses the concept and procedures of rounding numbers, exemplified by a practical problem of calculating total distance in a travel scenario. It emphasizes the importance and application of mathematical operations using variables to store and manipulate numeric values.
• 05:30 - 06:30: Understanding Integers and Floats The chapter discusses how to handle numerical data in programming using variables, focusing on integers and floats. It begins with an example of creating a variable to store the distance between two cities, New York City and Baltimore, and assigns it a value of 188 miles. Similarly, it demonstrates creating another variable for the distance between Baltimore and Pittsburgh, set at 247 miles. The chapter emphasizes the importance of variables in storing numerical distances and later calculating a total distance by combining these values.
• 06:30 - 08:00: Operator Precedence in Python The chapter discusses operator precedence in Python, using a practical example of calculating travel distance. It starts by assigning values to variables and explains how these can be used to determine the total distance of a journey. The process involves setting a speed (e.g., 65 miles per hour) and calculating the journey's total distance with the help of operators. The discussion is an exercise in understanding the importance of operator precedence in mathematical calculations and programming in Python.
• 08:00 - 09:30: Floating Point Precision This chapter discusses the calculation of travel time based on distance and speed. By assuming a constant driving speed of 65 miles per hour without breaks, the chapter emphasizes creating variables to represent speed (mph) and time. It also suggests calculating time by dividing the total distance by speed. The focus is on understanding these basic mathematical operations within the context of constant motion.
• 09:30 - 10:00: Conclusion The conclusion chapter focuses on explaining the basic mathematical concept of calculating time using distance and speed (in miles per hour). It emphasizes that the time can be easily determined by dividing the distance by the speed, a concept rooted in basic school-level mathematics. It further illustrates this with a practical example, displaying the calculation result as 6.69 hours, reinforcing the simplicity of the process.

3. Numbers [Python 3 Programming Tutorials] Transcription

• 00:00 - 00:30 today's topic is numbers in Python numbers are very important ingredient of any program I can't think of any software program in the world which doesn't use numbers so they're extremely important now in Python you can use Python programming language as a calculator so let me demonstrate that to you by doing some simple mathematical operations so for example you want to do addition of these two numbers you can do it like this so just type into numbers
• 00:30 - 01:00 and plus sign in between if you want to do subtraction you can do subtraction you can do division like this so for division you will use this last shine if you want to do multiplication you'll use star sign and it will multiply two numbers now if you want to find a remainder of a division then you will use a percentage sign so for example I
• 01:00 - 01:30 want to divide 11 by 2 and I want to find out the remainder for that you would use percentage sign like this and you can guess what will be the answer ok I think you guessed it right so 11 divided by 2 is that 2 into 5 is 10 and that remainder will be 1 you can also find the power of n numbers of for example you want to find 3 to the power of 2 then the way you do that is by
• 01:30 - 02:00 using 2 star sign 2 times so it will do this so 3 to the power of 2 is 9 guess what will be the answer of this this is 2 to the power of 4 ha 16 ok so when you are doing any number manipulation when you're writing any Python program
• 02:00 - 02:30 normally you would create variables to store these numbers and you will do these mathematical operations on those variables ok so let me let me demonstrate this by having a simple problem so for example you want to travel from New York to Baltimore and then from Baltimore to Pittsburgh and you don't know the distance between these cities now you want to find out the total distance so the way you do it
• 02:30 - 03:00 is you first create a variable to store the distance between New York City to Baltimore let's say it is 188 miles so I just created a variable called this an assign value 188 to it then you create another variable to store the distance between Baltimore to Pittsburgh and let's say this is 247 miles okay so to find out the total distance you create another variable called total distance
• 03:00 - 03:30 and you just assign those first two variables to it so when I do like this and if I bring the total distance it will tell me the total distance that I will be traveling during my journey okay another interesting problem could be let's say if you are driving at 65 miles per hour and you want to find the total
• 03:30 - 04:00 time that you will spend in your journey and we're just assuming you're not taking any breaks you are like a super human being you don't need any place you can just constantly drive okay so in that case again create another variable for your miles per hour speed so mph is equal to 65 this is your miles per hour and to find out the time you create another variable called time and say time equal to total distance if you have
• 04:00 - 04:30 total distance and if you have miles per hour how do you find out the time right it's a simple math it is distance divided by the speed so distance divided by miles per hour is your time it's just a simple high school math or school math so when you say time it prints this number so you see it's six point 69 hours now it is printing it with a
• 04:30 - 05:00 lot higher decimal precision you see like after dot you see so many decimal points if you want to see like just for simplicity if you want to see like two decimal points you can use this round function so in Python that is this function called down where the first argument is as you see it in the tooltip it's a number so your number is time and how many decimal points you want to see so you can say 2 so it is showing it as you see like after dot you you know see
• 05:00 - 05:30 only two decimal points one two if you want to see like three decimal point precision you can do this and it will show you three decimal points okay so just to summarize you can do all the basic mathematical operations in Python using these operator signs also there are two kind of numbers in Python one is integer which is like a whole number so for example for 30 by 16 2 for all these
• 05:30 - 06:00 are integer numbers because they don't have a fractional part to it whereas this number is called a float number because it has a fractional part it's not a whole number basically it has a fraction to it so just remember this thing the two types of numbers integers and floats alright now let me show you something interesting so if I do let's
• 06:00 - 06:30 say if I want to add and if I do this kind of operation just take a pause and think about what will be the answer what what will be the expected output ok all right so I'm just about to hit enter and you will see in a moment what it it prints now what were you expecting some of you might be expecting that it will do 10 plus 2 which is 12 and then it
• 06:30 - 07:00 will multiply it by 3 so 12 into 3 will be 36 but that's not what it printed why well the reason is the way python works is it has a priority on certain mathematical operations so for example in this case it will do 2 x 3 first so 2 x 3 is 6 and then it will add it to 10 so 10 plus 6 is 16 if you want to do what you expect
• 07:00 - 07:30 there which is 10 plus 2 and then multiply by 3 you need to use brackets so opening bracket 10 plus 2 closing bracket cross 3 so by providing these brackets you are telling your programming platform that I want the mathematical operation to happen in this order 10 plus 2 and then 3 now you get 36 ok cool now let me show you one more interesting thing so 6 minus 5.7 again take a pause and
• 07:30 - 08:00 think what will be the answer it's really easy to guess that right it should be 0.3 but let's see what happens whoo why the hell I got this answer why is it not 0.3 well there is an answer so in any programming language when you try to store floating number it ultimately numbers are stored in binary format which is a sequence of 0 and 1 and the
• 08:00 - 08:30 way floating numbers are stored they always lose the accuracy so there is no precise way to store floating numbers hence you will get this kind of behavior and this is not just with Python this is with any programming languages and it's expected so it's not a bug or anything it is an expected output so if you want to again see point 3 then use rounding number round rounding function so just say wrong this particular number by 2
• 08:30 - 09:00 decimal points and you get 0.3 ok so that was all about numbers thanks for watching