Procedural Programming: 01 Python Basics

Procedural Programming: Lesson 1 Part 2

Python Basics

​Statements & Expressions

• ​Python is an interpreted high-level programming language.

• ​A complete computer command is called a statement.

• ​For example: print("Hello World")

• ​An expression evaluates to a new value.

• ​For example: 2*2

Multiple Choice

What is a statement?

• A section of an algorithm

• A translation of machine code

• A precise description of a problem

• A complete computer command

Multiple Choice

Which function outputs text to the terminal?

• output()

• print()

• write()

• type()

​Variables

• ​We can store values in variables.

• ​To do this we use the assignment operator =

• For example: answer = 2*2

• ​Variables store values not expressions

• ​Good variable names describe the data they contain

Multiple Choice

How do we assign the number 10 to a variable?

• new variable_name = 10

• variable_name == 10

• def variable_name = 10

• variable_name = 10

Multiple Choice

What is the output of this code?

• cool_number

• 210

• 42

​Data Types

• All variables have a data type

• ​ints are whole numbers

• ​floats are decimal numbers

• ​strings are text

• ​Variables can be of any data type

• ​In Python, we don't need to declare variables, we can just use them by assigning a value

• ​For example:

Multiple Choice

Which of these variables is a string?

• cool_variable_1

• cool_variable_2

• cool_variable_3

• cool_variable_4

Multiple Choice

What is the difference between a float and an int?

• A float is text, int is a number

• A float is decimal, int is a whole number

• A float is a whole number an int is decimal

​Strings

• ​We can define strings on multiple lines

• We can combine string values to make a new string.

• ​Strings are combined using the + operator.

• This is called string concatenation.

• Strings are concatenated without spaces.

Multiple Choice

How do we define a multi-line string?

• ###

  Like this

  ###

• ***

  Like this

  ***

• """

  Like this

  """

Multiple Choice

How do you combine two strings?

• string1 + string2

• string1.combine(string2)

• string1.concatenate(string2)

​Comments

• We use comments to explain our code.

• Comments are ignored by programming languages.

• A comment in Python begins with the # character

• For example: #this is a comment​

Multiple Choice

What character begins a comment in Python?

• %

• *

• #

• /

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​Lovely Loveseat Project

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​User Input

• ​We can also use variables to store user input.

• ​We use input() to assign a user value to a variable.

• ​This requires a prompt message for the user.

• ​This is printed before they can enter data.

• ​For example:

​Working with Strings & Ints

• ​Python always accepts user input as a string.

• ​So we cannot perform calculations with it.

• ​We need to convert the input string to an int using the int() function

• ​For example:

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