Intro Python- Variables
Summary
TLDRThis educational video script introduces the concept of variables in programming, focusing on Python. It explains that variables store information like text or numbers which can be used later in a program. The script covers variable attributes: name, type, and value, using 'greeting' and 'my number' as examples. It differentiates between 'string' (text) and 'int' (integer) types, and briefly mentions 'float' (decimal numbers). The video also demonstrates how to create and update variables using assignment statements and how to print a variable's type using the 'type' function.
Takeaways
- 📚 Variables are a fundamental aspect of programming languages used to store information.
- 🔑 A variable has three characteristics: a name, a type, and a value.
- 🌐 The variable 'greeting' is used in the script to demonstrate a variable with the value 'hello, world'.
- 🔢 The variable 'my number' is shown with the value 50, illustrating how variables can store numerical data.
- 📝 The type 'str' stands for string, which is used for variables that contain text or a sequence of characters.
- 🔢 The type 'int' stands for integer, used for variables that contain whole numbers without decimal points.
- 💧 Strings can also be surrounded by single quotes in Python, but the course will use double quotes.
- 🔄 The 'float' type, which allows for decimal numbers, is mentioned as a future topic.
- 📝 Assignment statements in Python are used to create or update variables with an equal sign.
- 🔍 The 'type' function in Python can be used to print the type of a variable, such as 'str' or 'int'.
Q & A
What is a variable in programming?
-A variable is something that stores information in a program so that it can be used later. This information can be text or numbers.
What are the three characteristics of a variable?
-The three characteristics of a variable are its name, type, and value.
What is the name of the variable in the example program that stores the text 'hello world'?
-The name of the variable is 'greeting'.
What type is associated with the variable 'greeting' in the script?
-The type of the variable 'greeting' is 'str', which stands for string.
What does the type 'int' stand for and what kind of values can it hold?
-The type 'int' stands for integer and it can hold whole numbers, which can be positive, negative, or zero.
How can you print the value of a variable in Python?
-You can print the value of a variable in Python by using the 'print' function followed by the variable name without quotes.
What is the purpose of the 'type' function in Python?
-The 'type' function in Python is used to determine and print the data type of a variable.
What is a floating-point number and what is its Python type?
-A floating-point number is a number with a decimal component. In Python, this type of number is represented by the 'float' type.
How do you create or update a variable in Python?
-You can create or update a variable in Python using an assignment statement, which consists of the variable name on the left, an equal sign in the middle, and the value on the right.
Can you use single quotes to define a string in Python as mentioned in the script?
-While strings can be surrounded by single quotes in Python, the script specifies that double quotes will be used in this course.
What is the difference between 'int' and 'float' types in Python?
-The 'int' type represents integers without a decimal component, whereas 'float' represents numbers that can have a decimal component.
Outlines
💻 Introduction to Variables in Programming
This paragraph introduces the concept of variables in programming, which are fundamental to almost every programming language. The script explains variables through examples in a program, such as 'greeting' with the value 'hello, world' and 'my number' with the value 50. It defines a variable as something that stores information in a program for later use, which can be text or numbers. The paragraph further breaks down a variable into three characteristics: name, type, and value. For 'greeting', the type is 'str' (string), which contains text, and for 'my number', the type is 'int' (integer), which contains whole numbers. The paragraph also mentions the 'float' type for variables that can hold decimal numbers. It concludes by explaining how to create or update variables in Python using assignment statements with an equal sign.
Mindmap
Keywords
💡Variables
💡Name
💡Type
💡Value
💡String (str)
💡Integer (int)
💡Assignment Statement
💡Type Function
💡Floating-Point Number (float)
Highlights
Introduction to variables, a fundamental aspect of programming languages.
Explaining a program with a variable named 'greeting' that holds the value 'hello, world'.
Demonstration of printing a variable's value versus its type.
Definition of a variable as something that stores information to be used later in a program.
Variables have three characteristics: a name, a type, and a value.
Example of a variable 'greeting' with a name, type 'str', and value 'hello world'.
Explanation of the 'str' type for variables containing text or sequences of characters.
Clarification that strings can be surrounded by single quotes in Python, but double quotes will be used in the course.
Introduction to the 'int' type for variables containing whole numbers without decimals.
Examples of integers: positive, negative, and zero.
Introduction to the 'float' type for variables containing numbers with decimal components.
Explanation that the decimal component in floats can be zero, making 0.0 equal to the integer 0.
How to create or update a variable in Python using an assignment statement.
Structure of an assignment statement with variable name, equal sign, and value.
Using the 'type' function to print a variable's type, demonstrated with 'greeting'.
Using the 'type' function to confirm 'my number' variable's type as 'int'.
Anticipation of future lessons covering more advanced uses of variables.
Transcripts
alright welcome back in this video
you'll learn about something that is a
fundamental aspect of just about every
programming language variables let's
dive in and look at a program that has a
variable in it in a minute we'll take
some time to go over exactly what a
variable is and what it does the
variable in this program is called
greeting it has a value which is hello
world this means that printing greeting
is basically the same as printing hello
world
here's another program with a variable
the variable is called my number and its
value with the number 50 ok so what is a
variable a variable is something that
stores information in a program so that
it can be used later that information
can be something like hello world or the
number 50 more specifically a variable
has three things a name a type and a
value so let's look at the two variables
that we just saw and spell out each of
these three characteristics in the case
of variable greeting the name of the
variable is greeting the type of the
variable is ster which I'll explain in a
second and the value is hello world in
quotes
note that when you print the variable
greeting you don't put quotes around it
then we saw a variable whose name was my
number whose type was int which I'll
also explain in a second and whose value
is 50 okay so what do these types mean
stur is short for string a variable
whose type is ster contains text or a
sequence of zero or more characters and
these characters can be letters numbers
punctuation spaces whatever you can type
on your keyboard so hello world is an
example abc123 is an example or a string
can actually have zero characters okay
quick digression strings can also be
surrounded by single quotes in Python
however in this course we will use
double quotes now let's look at the type
int int is short for integer and a
variable whose type is int contains a
number and that number can be positive
negative or zero however it cannot have
a decimal component so negative 50 0 and
5 are all examples of integers another
type that we haven't seen yet but we
will in future lessons is float float is
short for floating-point number and this
is basically like an integer except it
does have a decimal component so
negative three point two zero point zero
or four point five six five two are all
examples of floats
note that the
Cemil component can be zero so zero
point zero is in fact equal to the
integers zero you can create a new
variable or update an existing variable
in python using what's called an
assignment statement this statement has
three parts on the left you have the
name of the variable on the right you
have the value that you want to give to
that variable and in the middle you just
have a single equal sign okay check out
this example program in the upper right
unlike the program that we saw a few
slides ago this program prints the type
of the variable greeting rather than the
value you can do this using the type
function the output is class stir in
triangle brackets and this might look a
little weird but the important part is
the part inside the single quotes stir
which is in fact the type of the
variable greeting now we can see the
type function being used on the variable
my number and sure enough the type is
int so that's the basics of variables in
Python in future videos you'll learn how
to do more interesting things with a
variable than just print its value or
its type
5.0 / 5 (0 votes)