Do you know what a string is in Python?

Summary: This article will tell you what a string is in Python and give you a brief introduction to everything you need to know about the concept.

This article will introduce the following content:

• How to create a string?
• How to access characters from string?
• Formatting Strings

So, let’s get started.

What are strings in Python?

Many of us who are familiar with C, C and other programming languages ​​will get answers such as "A string is a collection of characters or an array of characters".

The same is true in Python, we are talking about the same definition of the String data type. A string is an array of sequence characters and is written within single, double or triple quotes. Also, Python does not have a character data type, so when we write "a" it will be treated as a string of length 1.

Continue this article to learn what is String in Python?

How to create a string?

s = 'Hello'
print(s)
s1 = "Hello"
print(s1)
s2 = ''' Hello
How is the whether today? '''
print(s2)

Output:

Hello
Hello
Hello
How are you today?

When we use both single and double quotes in a string and when we want to write a multi-line sentence, triple quotes are usually used.

Notes

What we need to note is that when using single quotes, the string should not contain single quotes because if this happens, Python will assume The line ends without the second quote itself appearing and doesn't get the desired output. Identical symbols should be followed by double and triple quotes.

Continue this article to learn what is String in Python?

How to access characters from string?

Suppose we want to access a character in a string, say the last character, and we need to know its position in the string.

This is a string and the allocated position. So if you want to access 'n' from the string, you have to go to bit 5.

Numbering or indexing starts from 0 to 1 which is less than the length of the string.

This is a python program that can make us more clear.

str = 'Antarctica is really cold.'
print('str = ', str)
#first character
print('str[0] = ', str[0])
#last character
print('str[-1] = ', str[-1])
#slicing 2nd to 5th character
print('str[1:5] = ', str[1:5])
#slicing 6th to 2nd last character
print('str[5:-2] = ', str[5:-2])

Output:

str = It’s really cold in Antarctica.
str [0] = A
str [-1] =.
str[1:5] = ntar
str[5:-2] = ctica is indeed col

Now if in index following increasing order pattern from left to right then from right To the left follows a descending order pattern, i.e. from -1, -2, -3 etc. So if you want to access the last character, you can do it in two ways.

str = 'Antarctica is really cold.'
a = len(str)
print('length of str ', a)
#last character with the help of length of the string
print('str[a] ', str[a-1])
#last character with the help of indexing
print('str[-1] ',str[-1])

Output:

str 26
The length of str [a].
str[-1].

Strings are immutable by nature, which means that once a string is declared, no characters in it can be changed.

s = "Hello Batman"
print(s)
s[2] = 'P'
print(s)

Output:

Hello Batman
Traceback (most recent call):
File "C:/Users/prac.py" , line 3, at
s[2] =' P'TypeError
: 'str' object does not support item allocation

Process completed with exit code 1

However, You can delete the entire string using del operator.

s = "Hello Batman"
print(s)
del s
print(s)

Output:

Hello Batman
Traceback (most recent call):
File "C:/Users/prac.py" ,
Line 4 in print
NameError: name 's' is not defined

Process completed with exit code 1

If you don't want s to be "Hello Batman", If you want it to be another string, you can update the string as a whole.

s = "Hello Batman"
print(s)
s = "Hello Spiderman"
print(s)

Output:

Hello Batman
Hello Spider-Man

Continue this article to learn what is String in Python?

Format string:

Format string means that the string can be allocated dynamically at any position.

You can use the format() method to format strings in Python, which is a very powerful tool for formatting strings. The Format method in String contains curly braces {} as placeholders, which can save parameters to specify the order based on position or keyword.

String1 = "{} {} {}".format('Hello', 'to', 'Batman')
print("Default order: ")
print(String1)
# Positional Formatting
String1 = "{1} {0} {2}".format('Hello', 'to', 'Batman')
print("nPositional order: ")
print(String1)
# Keyword Formatting
String1 = "{c} {b} {a}".format(a='Hello', b='to', c='Spiderman')
print("nString in order of Keywords: ")
print(String1)
# Formatting of Integers
String1 = "{0:b}".format(20)
print("binary representation of 20 is ")
print(String1)
# Formatting of Floats
String1 = "{0:e}".format(188.996)
print("nExponent representation of 188.996 is ")
print(String1)
# Rounding off Integers
String1 = "{0:.2f}".format(1 / 6)
print("none-sixth is : ")
print(String1)
# String alignment
String1 = "|{:<10}|{:^10}|{:>10}|".format('Hello', 'to', 'Tyra')
print("nLeft, centre and right alignment with Formatting: ")
print(String1)

Output:

Default order:
Hello from Batman

Position order:
To Hello Batman

The strings are arranged in keyword order:
The binary representation of Spider-Man to Hello

20 is 10100

The exponent of 188.996 is represented as
1.889960e 02

One sixth is:
0.17

Left aligned, center aligned and right aligned, the format is:
|Hello| To| Terra|

Strings can be left-justified (<), right-justified (>), or centered (^) using the formatting methods.

{:<10} .format("Hello") means that Python will reserve 10 spaces for the string, and the string will start from the left. The same goes for right and center alignment.

I hope you learn these concepts well and try to make them more accurate.

Related free learning recommendations: python video tutorial

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