In this video, we’ll talk about dictionaries and sets. For strings, lists, and tuples, we have been using integers as the indices and position numbers in order to get their values. Dictionaries are similar to lists except that instead of using integers as the indices, dictionaries can use any string or number or immutable type as the index. Let’s create a dictionary to demonstrate how it works. We will create a dictionary called states. Instead of using number indices, we...
Tagged: Computer Science
Introduction to Python – Chapter 8 – Lists, Matrices, and Tuples
In the last video, we talked about lists. There are a couple of more things that we need to talk about lists including matrices. Let’s say that we had two lists:
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a = [1, 2, 3, 4, 5] b = a |
With lists, a and b are the same thing. If I change b, then a is also changed. Let’s test changing b.
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b[0] = 0 print(a) |
When we run the program, we can see that even though a was a list with 1, 2, 3, 4, and 5, and we didn’t...
Introduction to Python – Chapter 7 – Lists
In this video, we’ll talk about lists. List is the term used for an ordered sequence of values where each value has an index. Before we continue to talk about lists, there is also a term called arrays from other programming languages that you might have heard about. Arrays are almost exactly like lists in Python. There’s an array module in Python for using arrays. In Python, arrays can only hold data of the same type. Lists can hold multiple...
Introduction to Python – Chapter 6 – Strings and For Loops
In this video, we’ll talk more about strings and explain the for loop. A string is a data type created when we use a pair of quotation marks.
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username = "microwavesam" |
is an example of a string. Let’s say that I wanted to get the “m” character in “microwavesam”. A character is the term used for a single symbol in Python. In Python and programming languages, we also use the term, element. An element is a term for any individual part of...
Introduction to Python – Chapter 5 – Iteration and While Loops
We talked about recursion and iteration in the last tutorial. Recursion is the term used when you call the same function inside a function, which causes repetition since you’re repeating the function. Iteration is the term used when you repeat steps without using recursion. This video will be about making iteration or repeating steps easier! In tutorial #2, we talked about most recent assignment because we talked about how you can assign a variable multiple times. A variable takes the...
Introduction to Python – Chapter 4 – Return and Recursion
In this video, we’ll talk about return statements and recursion. In a previous video, we talked about how the value that you get from a function is the return value. If I call type(4), I get the return value of int. How does the type() function return the type int value? Let’s write a function that adds two numbers and returns the result the same way how the type() function gets a result.
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def add_two_numbers(num1, num2): result = num1 + num2 return result |
Notice how the function uses the...
Introduction to Python – Chapter 3 – Conditionals
In this video, we’ll talk about more operators you can use, conditionals, and recursion. We’ve talked about the basic operators in the previous videos. Operators like plus, minus, multiply, and division. A very commonly used operator is modulus or also called modulo. What’s modulus? Modulus works on integers and finds the remainder when dividing two numbers. The modulus operator is the percent sign (%). For example,
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remainder = 7 % 3 print(remainder) |
Think of dividing 7 by 3, but what gets returned is the remainder,...
Introduction to Python – Chapter 2 – Types and Functions
This video will expand on the basic concepts that we talked about in the previous video. In the first video, we talked about a terminology called assignment. x = 5 is an assignment. You assign values to variables. A variable can be assigned many times, and it always keeps the value of its most recent assignment. If I do, x = 7, it replaces x = 5. You can do x = x + 1, which adds 1 to its...
Introduction to Python – Chapter 1 – Intro and Variables
Intro Computer Science is not the study of computers nor is it only about programming. Sometimes, when people hear about Computer Science, they think oh, computers and programming! In reality, computers are just a tool in computer science, and programming simply executes a sequence of instructions that we create. Computer Science is all about computation, asking the question: “What exactly can be computed, how can we compute it, and how fast we can compute it?” Computation is a fancy way...
