Python строка добавить символы

Добавление символа в строку в Python: лучшие способы и примеры

Добавление символа в строку в Python: лучшие способы и примеры

Вставка символов в строку – это часто встречающаяся задача при работе с текстом на Python. В этой статье мы рассмотрим различные методы вставки символов в строку и предоставим примеры кода для каждого из них.

1. Конкатенация строк

Конкатенация – это простой и интуитивно понятный способ добавления символа или строки к существующей строке. Мы можем использовать оператор + для соединения двух строк вместе.

s = "Hello, World!" char_to_insert = "X" position = 7 new_s = s[:position] + char_to_insert + s[position:] print(new_s) # Вывод: "Hello, XWorld!"

В этом примере мы добавляем символ «X» на позицию 7 в строку «Hello, World!».

2. Использование списков

Так как строки в Python являются неизменяемыми объектами, использование списков может быть более эффективным, особенно при множественных операциях вставки. Мы можем преобразовать строку в список, вставить символ и затем преобразовать список обратно в строку с помощью метода join() .

s = "Hello, World!" char_to_insert = "X" position = 7 s_list = list(s) s_list.insert(position, char_to_insert) new_s = ''.join(s_list) print(new_s) # Вывод: "Hello, XWorld!"

3. Использование строковых методов

Метод str.format() позволяет вставить значения в определенные позиции строки, используя фигурные скобки <> в качестве заполнителей.

s = "Hello, World!" char_to_insert = "X" position = 7 new_s = '<><><>'.format(s[:position], char_to_insert, s[position:]) print(new_s) # Вывод: "Hello, XWorld!"

Мы также можем использовать f-строки, доступные начиная с Python 3.6, для более удобной записи.

s = "Hello, World!" char_to_insert = "X" position = 7 new_s = f'' print(new_s) # Вывод: "Hello, XWorld!"

4. Использование стека

Стек – это структура данных, основанная на принципе «последний вошел, первый вышел» (LIFO). Мы можем использовать стек для хранения символов строки, вставить символ на нужную позицию и затем извлечь символы в новую строку.

def insert_char(s, char_to_insert, position): stack = list(s) new_s = "" for i in range(len(stack) + 1): if i == position: new_s += char_to_insert else: new_s += stack.pop(0) return new_s s = "Hello, World!" char_to_insert = "X" position = 7 new_s = insert_char(s, char_to_insert, position) print(new_s) # Вывод: "Hello, XWorld!"

6. Использование метода str.replace()

Метод str.replace() заменяет все вхождения подстроки на другую подстроку. Мы можем использовать этот метод для вставки символа, заменяя определенный символ или подстроку на исходную подстроку плюс символ для вставки.

s = "Hello, World!" char_to_insert = "X" position = 7 char_to_replace = s[position] new_s = s.replace(char_to_replace, char_to_insert + char_to_replace, 1) print(new_s) # Вывод: "Hello, XWorld!"

Заключение

Каждый из представленных методов имеет свои преимущества и недостатки. Конкатенация строк является простым и интуитивным способом, но может быть неэффективным для больших строк или множественных операций вставки. Использование списков и стеков предлагает более гибкий подход, но может быть менее эффективным для небольших операций. Строковые методы, такие как str.format() и f-строки, предоставляют удобную запись, но могут быть сложными для понимания для новичков.

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Append to a string Python + Examples

Let’s see how to append to a string python.

In this example, we will use “+” operator to append to a string in python. The code below shows appending of two string.

s1 = "New" s2 = "Delhi" space = " " print(s1 + space + s2)

You can refer to the below screenshot to see the output for append to a string python.

Append to a string python

This is how we can append to a string in Python.

Prepend to a string python

Now, we will see how to prepend to a string python.

Prepend to a string will add the element to a string. In this example, we have two strings and to get the output we will print my_string.

my_string = "Python" add_string = " is famous" my_string += add_string print("The string is : " + my_string)

You can refer to the below screenshot to see the output for prepend to a string python

Prepend to a string python

This is how we can prepend a string in Python.

Insert to a string python

Here, we will see how to insert to a string python.

  • To insert into a string we will use indexing in python.
  • Inserting into a string returns the string with another string inserted into it at a given index.
  • In this example, we are inserting “New York” into “Los Angeles, Chicago” and it returns “Los Angeles, New York, Chicago”.
str1 = "Los Angeles, Chicago" str2 = "New York, " beg_substr = str1[:7] end_substr = str1[7:] my_str = beg_substr + str2 + end_substr print(my_str)

This is how we can insert to a sting in Python.

Append 0 to a string python

Let’s see how to append 0 to a string python.

In this example, we will use rjust function for appending 0 to a string as it offers a single line way to perform the task.

t_str = 'New' N = 1 res = t_str.rjust(N + len(t_str), '0') print("The string after adding zeros : " + str(res))

You can refer to the below screenshot to see the output for append 0 to a string python.

Append 0 to a string python

The above Python code we can use to append 0 to a string in Python.

Append character to a string python

Now, we will see how to append character to a string python.

  • To append a character to a string we will insert the character at an index of a string and it will create a new string with that character.
  • To insert a character we will use slicing a_str[:1] + “n” + a_str[1:] and the “+” operator is used to insert the desired character.
a_str = "Hello" a_str = a_str[:1] + "n" + a_str[1:] print(a_str)

You can refer to the below screenshot to see the output for append character to a string python

Append character to a string python

This is how to append character to a string in Python.

Python append to beginning of a string in a loop

Here, we will see Python append to the beginning of a string in a loop

In this example, we will append to the beginning of a string using the for loop, and the “+” operator is used.

endstr = "People" my_list = ['Hello', 'to', 'all'] for words in my_list: endstr = endstr + words print("The string is: " + endstr)

You can refer to the below screenshot to see the output for python add to string in a loop.

Python append to the beginning of a string in a loop

The above code, we can use to append to beginning of a string in a loop in Python.

Add letter to a string python

Here, we will see how to add letter to a string python.

To add letter to a string python we will use f”” and to get the output we will print(res).

str1 = "Python" l2 = "G" res = f"" print(res)

You can refer to the below screenshot to see the output for add letter to a string python

Add letter to a string python

This is python code to add letter to a string in Python.

Add variable to a string python

Let’s see how to add variable to a string python.

In this example, we will use “+” operator to add a variable to a string.

var = "Guides" print("Python " + var + " for learning")

You can refer to the below screenshot to see the output for add variable to a string python

Add variable to a string python

This is how to add variable to a string in Python.

Add int to a string python

Now, we will see how to add int to a string python.

Firstly, we will initialize the string and a number and by using the type conversion we will insert the number in the string, and then to get the output we will print.

t_str = "Python" t_int = 8 res = t_str + str(t_int) + t_str print("After adding number is : " + str(res))

You can refer to the below screenshot to see the output for add int to a string python

Add int to a string python

This is how to add int to a string in Python.

Append to end of a string in python

Here, we will see how to append to the end of a string in python

In this example, we will use the “+” operator, and to get the output we will print(string3).

string1 = "Hello Wo" string2 = "rld" string3 = string1 + string2 print(string3)

You can refer to the below screenshot to see the output for append to the end of a string in python.

Append to the end of a string in python

The above code we can use to append to end of a string in python.

How to append a new line to a string in python

Let us see how to append a new line to a string in python

In this example, to append a new line to a string we have specified the newline character by using “\n” which is also called an escape character. Hence, the string “to python” is printed in the next line.

my_string = "Welcome\n to python." print(my_string)

You can refer to the below screenshot to see the output for how to append a new line to a string in python.

How to append a new line to a string in python

The above code we can use to append a new line to a string in python.

How to append backslash to a string in python

Now, we will see how to append backslash to a string in python

In this example, to append backslash to a string in python we have used the syntax “\\” to represent single backslash to a string.

my_str1 = "Hello" my_str2 = "\\" res = my_str1 + my_str2 print(res)

You can refer to the below screenshot to see the output for how to append backslash to a string in python.

How to append backslash to a string in python

The above code we can use to append backslash to a string in python.

How to append to an empty string in python

Let’s see how to append to an empty string in python.

To append to an empty string in python we have to use “+” operator to append in a empty string.

str = "" res = str + "Hello World" print(res)

You can refer to the below screenshot to see the output for how to append to an empty string in python.

How to append to an empty string in python

The above code we can use to append to an empty string in python.

How to append double quotes to a string in python

Here, we will see how to append double quotes to a string in python.

To append double quotes to a string in python we have to put the string in the single quotes.

double_quotes = '"Python"' print(double_quotes)

You can refer to the below screenshot to see the output for how to append double quotes to a string in python.

How to append double quotes to a string in python

The above code we can use to append double quotes to a string in python.

How to append to a string in python

In python, to append a string in python we will use the ” + ” operator and it will append the variable to the existing string.

name = 'Misheil' salary = 10000 print('My name is ' + name + 'and my salary is around' + str(salary))

After writing the above Python code (how to append to a string in python), Ones you will print then the output will appear ” My name is Misheil and my salary is around 10000 “. Here, the ” + ” operator is used to append the variable. Also, you can refer to the below screenshot append to a string in python.

How to append to a string in python

In this Python tutorial, we have learned about how to Append to a string python. Also, we covered these below topics:

  • Append to a string python
  • Prepend to a string python
  • Insert to a string python
  • Append 0 to a string python
  • Append character to a string python
  • Python append to the beginning of a string in a loop
  • Add letter to a string python
  • Add variable to a string python
  • Add int to a string python
  • Append to the end of a string in python
  • How to append a new line to a string in python
  • How to append backslash to a string in python
  • How to append to an empty string in python
  • How to append double quotes to a string in python
  • How to append to a string in python

I am Bijay Kumar, a Microsoft MVP in SharePoint. Apart from SharePoint, I started working on Python, Machine learning, and artificial intelligence for the last 5 years. During this time I got expertise in various Python libraries also like Tkinter, Pandas, NumPy, Turtle, Django, Matplotlib, Tensorflow, Scipy, Scikit-Learn, etc… for various clients in the United States, Canada, the United Kingdom, Australia, New Zealand, etc. Check out my profile.

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