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:
Assigning a string to a variable is done with the variable name followed by an equal sign and the string:
You can assign a multiline string to a variable by using three quotes:
You can use three double quotes:
a = """Lorem ipsum dolor sit amet,
consectetur adipiscing elit,
sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua."""
print(a)
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Or three single quotes:
a = '''Lorem ipsum dolor sit amet,
consectetur adipiscing elit,
sed do eiusmod tempor incididunt
ut labore et dolore magna aliqua.'''
print(a)
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Note: in the result, the line breaks are inserted at the same position as in the code.
Like many other popular programming languages, strings in Python are arrays of bytes representing unicode characters.
However, Python does not have a character data type, a single character is simply a string with a length of 1.
Square brackets can be used to access elements of the string.
Get the character at position 1 (remember that the first character has the position 0):
a = "Hello, World!"
print(a[1])
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Since strings are arrays, we can loop through the characters in a string, with a for
loop.
Loop through the letters in the word "banana":
for x in "banana":
print(x)
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Learn more about For Loops in our Python For Loops chapter.
To get the length of a string, use the len()
function.
The len()
function returns the length of a string:
a = "Hello, World!"
print(len(a))
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To check if a certain phrase or character is present in a string, we can use the keyword in
.
Check if "free" is present in the following text:
txt = "The best things in life are free!"
print("free" in txt)
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Use it in an if
statement:
Print only if "free" is present:
txt = "The best things in life are free!"
if "free" in txt:
print("Yes, 'free' is present.")
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Learn more about If statements in our Python If...Else chapter.
To check if a certain phrase or character is NOT present in a string, we can use the keyword not in
.
Check if "expensive" is NOT present in the following text:
txt = "The best things in life are free!"
print("expensive" not in txt)
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Use it in an if
statement:
print only if "expensive" is NOT present:
txt = "The best things in life are free!"
if "expensive" not in txt:
print("No, 'expensive' is NOT present.")
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