Anything inside a single(‘) or double(“) quotes in Python is considered to be a string generally i.e if you put anything inside single or double quotes then it will be considered as a Python Strings e.g. “string”, ‘string’, “I Am A String”, etc.
Printing a String
We use the “print()” statement to print a string in the terminal.
Example
print("Hello,I am a string")
print('Hello,I am also a string')
Output
Hello,I am a string Hello,I am also a string
Assigning String to Variable
Example
a = "Hello" b = """This is a multiline string""" c = '''This is also a multiline string''' print(a) print(b) print(c)
Output
Hello This is a multiline string This is also a multiline string
Indexing in Strings
Python provides both types of indexing i.e. positive and negative.
Positive indexing starts from the left end with “0” and negative indexing starts from the right end with “-1“.
String Slicing
String slicing means choosing or returning some characters from the string. In python, anything inside single or double quotes is considered to be a string and the spaces are also counted during the indexing of a string.
Example
mystr = "I am a string"
print(len(mystr)) # 13
print(mystr[0]) # 'I'
print(mystr[1]) # ' ' blank space
print(mystr[0:len(mystr)]) # full string
print(mystr[:]) # here python automatically assigns 0 and
# value of length of string
print(mystr[-2:-1]) # 'n'
print(mystr[-14:-1]) # full string excluding 'g'
print(mystr[:100]) # full string (no errors)
Output
13 I I am a string I am a string n I am a strin I am a string
Note: Here the second value after “:” is subtracted by “1”.
String Concatenation
String concatenation means to add two strings. We use the “+” operator to concatenate strings.
Example-1
x = "Hello "
y = "World"
z = x + y
print(x + y)
print("Hello " + "World")
print(z)
Output
Hello World Hello World Hello World
Let’s see one more example–
Example-2
x = "2"
y = "4"
print("12.3" + "34.6") # string concatenation
print(x + y) # string concatenation
print(int(x) + int(y)) # simple addition
Output
12.334.6 24 6
Comma in print() statement
We use comma(,) inside the print() statement with many objects or data types like strings, functions, lists, sets, etc.
But its working is something like it creates a space between two objects inside print() statement whether it is a string or list or any other object or datatype.
We can use commas to separate strings and numbers in print() statements.
Example
print("This name is", "Harry")
print("My roll number is", 21)
Output
This name is Harry My roll number is 21
“end” inside print() statement
We use the “end” inside the print() statement to insert some characters including space at the end of the string and also we can restrict the print() statement to not change the line which the print() statement does by default.
Example
print("Hello")
print("World")
print("Hello", end="") # no line change will happen
print("World")
print("Hello", end=" ") # no line change only space will be inserted
print("World")
print("Hello", end=" my ") # inserting my between Hello and World
print("World")
Output
Hello World HelloWorld Hello World Hello my World
format() method
We can use the format() method after strings which are used to insert specified values inside strings.
We use “{}” to insert specified values.
There are three ways to insert values.
1. {valuename}
2. {valueindex}
3. {}
Example
print("Name:{name} and age:{age}".format(name="Harry", age=30))
print("Name:{0} and age:{1}".format("Harry", 30))
print("Name:{1} and age:{0}".format("Harry", 30))
print("Name:{} and age:{}".format("Harry", 30))
Output
Name:Harry and age:30 Name:Harry and age:30 Name:30 and age:Harry Name:Harry and age:30
Fast String
Denoted with “f“, the fast string also works the same as the format() method, but this makes work easier and faster. See the example below-
Example
name = "Harry"
age = 30
print(f"Name:{name} and age:{age}")
print(f"Addition:{5+4}")
print(f"Multiplication:{eval('1+2//4-20*9')}")
''' eval() is a built-in function
used to calculate a string
which contains some arithematic
calculations of numbers'''
Output
Name:Harry and age:30 Addition:9 Multiplication:-179
String Length
We use “len()” to know the length of any string.
Example
a = "Hello" b = """This is a multiline string""" c = '''This is also a multiline string''' print(len(a)) print(len(b)) print(len(c))
Output
5 27 31
lower() method
If we type “stringname.lower()” then this method will return the string having all letters in lowercase.
Example
mystring = "I Am A String" print(mystring.lower())
Output
i am a string
upper() method
If we type “stringname.upper()” then this method will return the string with all letters to uppercase.
Example
mystring = "I Am A String" print(mystring.upper())
Output
I AM A STRING
replace() method
This method is used to replace a string or letters with another string.
Example
mystring = "I Am A String"
print(mystring.replace("I", "This"))
Output
This Am A String
Escape Characters
If we want to output– I am “A” string using the code– print(“I am “A” string”), then python will give you a syntax error.
Example
print("I am "A" string")
Output
File "f:/vscode/python/escape.py", line 1
print("I am "A" string")
^
SyntaxError: invalid syntaxIf we use backslash “\” followed by the character like ” then the problem will get resolved.
Hence, an escape character is a backslash followed by a character you want.
Example
print("I am \"a\" String")
print("Printing in \nNew Line")
print("Printing with a \ttab space")
print("Printing a single quote\'")
Output
I am "a" String Printing in New Line Printing with a tab space Printing a single quote'
Important Escape Characters
| Escape Character | Name |
|---|---|
| \’ | Single Quote |
| \\ | Backslash |
| \n | New Line |
| \t | Tab |
| \b | Backspace |
| \” | Double Quote |
Also Read:
