mylist = ["apple", "banana", "cherry"]
Lists are used to store multiple items in a single variable.
Lists are one of 4 built-in data types in Python used to store collections of data, the other 3 are Tuple, Set, and Dictionary, all with different qualities and usage.
Lists are created using square brackets: Continue reading Python Lists
Operators are used to perform operations on variables and values.
In the example below, we use the + operator to add together two values:
print(10 + 5)
Python divides the operators in the following groups:
Arithmetic operators are used with numeric values to perform common mathematical operations: Continue reading Python Operators
Booleans represent one of two values: True or False.
In programming you often need to know if an expression is True or False.
You can evaluate any expression in Python, and get one of two answers, True or False.
When you compare two values, the expression is evaluated and Python returns the Boolean answer: Continue reading Python Booleans
Python has a set of built-in methods that you can use on strings.
Note: All string methods return new values. They do not change the original string.
To insert characters that are illegal in a string, use an escape character.
An escape character is a backslash \ followed by the character you want to insert.
An example of an illegal character is a double quote inside a string that is surrounded by double quotes:
You will get an error if you use double quotes inside a string that is surrounded by double quotes:
txt = "We are the so-called "Vikings" from the north."
To fix this problem, use the escape character \": Continue reading Python – Escape Characters
As we learned in the Python Variables chapter, we cannot combine strings and numbers like this:
age = 36
txt = "My name is John, I am " + age
print(txt)
But we can combine strings and numbers by using f-strings or the format() method!
To concatenate, or combine, two strings you can use the + operator.
Merge variable a with variable b into variable c:
a = "Hello"
b = "World"
c = a + b
print(c)
Python has a set of built-in methods that you can use on strings.
The upper() method returns the string in upper case:
a = "Hello, World!"
print(a.upper())
The lower() method returns the string in lower case:
a = "Hello, World!"
print(a.lower())
You can return a range of characters by using the slice syntax.
Specify the start index and the end index, separated by a colon, to return a part of the string.
Get the characters from position 2 to position 5 (not included):
b = "Hello, World!"
print(b[2:5])
Note: The first character has index 0.
Strings in python are surrounded by either single quotation marks, or double quotation marks.
‘hello’ is the same as “hello”.
You can display a string literal with the print() function:
print("Hello")
print('Hello')
You can use quotes inside a string, as long as they don’t match the quotes surrounding the string: Continue reading Python Strings