Repeat string n times python

Repeat string n times python

Last updated: Feb 21, 2023
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# Table of Contents

# Repeat a string N times in Python

Use the multiplication operator to repeat a string N times, e.g. new_str = my_str * 2 .

The multiplication operator will repeat the string the specified number of times and will return the result.

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my_str = 'bobby' # ✅ Repeat a string N times new_str = my_str * 2 print(new_str) # 👉️ bobbybobby # --------------------------------------- # ✅ Repeat a substring N times new_str = my_str[0:3] * 2 print(new_str) # 👉️ bobbob # --------------------------------------- # ✅ Repeat a string N times with a separator new_str = ' '.join([my_str] * 2) print(new_str) # 👉️ bobby bobby 

The first example uses the multiplication operator to repeat a string N times.

When the multiplication operator is used with a string and an integer, it repeats the string the specified number of times.

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print('ab-' * 2) # 👉️ ab-ab- print('ab-' * 3) # 👉️ ab-ab-ab- 

If you need to repeat a substring N times, use string slicing.

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my_str = 'bobby' new_str = my_str[0:3] * 2 print(new_str) # 👉️ bobbob 

The syntax for string slicing is my_str[start:stop:step] .

Python indexes are zero-based, so the first character in a string has an index of 0 , and the last character has an index of -1 or len(my_str) — 1 .

# Repeat an integer multiple times using the multiplication operator

If you need to print an integer multiple times, make sure to convert it to a string before using the multiplication operator.

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my_int = 9 print(str(my_int) * 4) # 👉️ '9999' 

# Repeat a string multiple times using a formatted string literal

You can also use a formatted string literal to print a string multiple times.

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my_str = 'z' result = f'Result: my_str * 4>' print(result) # 👉️ Result: zzzz 

Formatted string literals (f-strings) let us include expressions inside of a string by prefixing the string with f .

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my_num = 100 print(f'my_num>' * 2) # 👉️ 100100 print(f'my_num> ' * 2) # 👉️ 100 100 

Make sure to wrap expressions in curly braces — .

# Repeat a string to a certain length in Python

To repeat a string to a certain length:

1. Multiply the string by the specified length to repeat it N times.
2. Use string slicing to select a part of the string from index 0 up to the specified length.

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def repeat_to_length(string, length): return (string * (length//len(string) + 1))[:length] print(repeat_to_length('asd', 6)) # 👉️ asdasd print(repeat_to_length('asd', 4)) # 👉️ asda 

The first thing to note is that we can repeat a string by multiplying it with an integer.

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print('asd' * 2) # 👉️ 'asdasd' 

The first function aims to repeat the string fewer times and might be a little faster for longer strings.

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def repeat_to_length(string, length): return (string * (length//len(string) + 1))[:length] print(repeat_to_length('asd', 6)) # 👉️ asdasd print(repeat_to_length('asd', 4)) # 👉️ asda 

The function takes the string and the desired length as arguments and repeats the string to the specified length.

We used the floor division // operator to get an integer from the division.

Division / of integers yields a float, while floor division // of integers results in an integer.

The result of using the floor division operator is that of a mathematical division with the floor() function applied to the result.

This is important because division / of integers always returns a float , and trying to multiply a string by a float would raise a TypeError .

The last step is to use string slicing to get a part of the string from index 0 up to the specified length.

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print('asdasd'[:4]) # 👉️ 'asda' print('asdasd'[:3]) # 👉️ 'asd' 

The syntax for string slicing is my_str[start:stop:step] , where the start value is inclusive and the stop value is exclusive.

This is exactly what we need because indexes are zero-based in Python. In other words, the last index in a string is len(my_str) — 1 .

# Repeat a string to a certain length by multiplying

Alternatively, you can use a simpler and more direct approach by multiplying the string by the provided length and getting a slice of the string up to the specified length .

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def repeat_to_length_2(string, length): return (string * length)[:length] print(repeat_to_length_2('asd', 6)) # 👉️ asdasd print(repeat_to_length_2('asd', 4)) # 👉️ asda 

We multiply the string by the specified length to repeat it N times.

The string is repeated many more times than necessary, but this is probably not going to be an issue if working with relatively short strings.

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# 👇️ asdasdasdasdasdasd print('asd' * 6) # 👇️ asdasd print('asdasdasdasdasdasd'[:6]) 

This approach might be slower for longer strings, but it is much easier to read.

# Repeat a string N times with a separator in Python

If you need to repeat a string N times with a separator:

1. Wrap the string in a list and multiply it by N.
2. Use the str.join() method to join the list of strings.
3. The str.join() method will join the repeated strings with the provided separator.

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my_str = 'bobby' new_str = ' '.join([my_str] * 2) print(new_str) # 👉️ bobby bobby new_str = ' '.join([my_str] * 3) print(new_str) # 👉️ bobby bobby bobby new_str = '-'.join([my_str] * 2) print(new_str) # 👉️ bobby-bobby 

We wrapped the string in square brackets to pass a list to the str.join() method.

When the multiplication (*) operator is used with a list and an integer, it repeats the items in the list N times.

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print(['bobby'] * 2) # 👉️ ['bobby', 'bobby'] print(['bobby'] * 3) # 👉️ ['bobby', 'bobby', 'bobby'] print(['a', 'b'] * 2) # 👉️ ['a', 'b', 'a', 'b'] 

Once we have a list containing the string N times, we can use the str.join() method.

The str.join method takes an iterable as an argument and returns a string which is the concatenation of the strings in the iterable.

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my_str = 'bobby' new_str = ' '.join([my_str] * 2) print(new_str) # 👉️ bobby bobby 

The string the method is called on is used as the separator between the elements.

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my_str = 'bobby' new_str = '-'.join([my_str] * 2) print(new_str) # 👉️ bobby-bobby 

If you need to repeat a slice of a string N times with a separator, use string slicing.

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my_str = 'bobbyhadz.com' new_str = ' '.join([my_str[0:5]] * 2) print(new_str) # 👉️ bobby bobby 

The syntax for string slicing is my_str[start:stop:step] .

Python indexes are zero-based, so the first character in a string has an index of 0 , and the last character has an index of -1 or len(my_str) — 1 .

The slice my_str[0:5] starts at index 0 and goes up to, but not including index 5 .

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my_str = 'bobbyhadz.com' print(my_str[0:5]) # 👉️ 'bobby' 

Make sure to wrap the slice in square brackets to pass a list to the str.join() method.

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my_str = 'bobbyhadz.com' new_str = ' '.join([my_str[0:5]] * 2) print(new_str) # 👉️ bobby bobby 

If you pass a string to the method, the string would get split on each character.

If you use the more manual approach of adding the separator with the addition (+) operator and using the multiplication operator, you’d get a trailing separator.

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my_str = 'bobby' new_str = (my_str + '-') * 3 print(new_str) # 👉️ bobby-bobby-bobby- 

Notice that there is a hyphen at the end of the string.

You could use the str.rstrip() method to remove the hyphen, but the str.join() method approach is more elegant and intuitive.

# Repeat each character in a string N times in Python

To repeat each character in a string N times:

1. Use a generator expression to iterate over the string.
2. Use the multiplication operator to repeat each character N times.
3. Use the str.join() method to join the object into a string.

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my_str = 'asd' N = 2 new_str = ''.join(char * N for char in my_str) print(new_str) # 👉️ aassdd 

We used a generator expression to iterate over the string.

Generator expressions are used to perform some operation for every element or select a subset of elements that meet a condition.

On each iteration, we use the multiplication operator to repeat the character N times.

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my_str = 'asd' # 👇️ ['aa', 'ss', 'dd'] print([char * 2 for char in my_str]) 

The last step is to use the str.join() method to join the strings in the generator object into a single string.

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my_str = 'asd' N = 3 new_str = ''.join(char * N for char in my_str) print(new_str) # 👉️ aaasssddd 

The str.join method takes an iterable as an argument and returns a string which is the concatenation of the strings in the iterable.

The string the method is called on is used as the separator between the elements.

We used an empty string as the separator to join the strings in the generator object without a delimiter.

Alternatively, you can use the map() function.

# Repeat each character in a string N times using map()

This is a three-step process:

1. Pass a lambda function and the string to the map() function.
2. The lambda function should repeat each character N times.
3. Use the str.join() method to join the map object into a string.

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my_str = 'asd' N = 3 new_str = ''.join(map(lambda char: char * N, my_str)) print(new_str) # 👉️ aaasssddd 

The map() function takes a function and an iterable as arguments and calls the function with each item of the iterable.

The lambda function we passed to map gets called with each character in the string.

The function uses the multiplication operator to repeat the character N times and returns the result.

The last step is to use the str.join() method to join the map object into a string.

Which approach you pick is a matter of personal preference. I’d use a generator expression because I find them quite direct and easy to read.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

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Repeat String N Times in Python

1. Repeat String N Times With the * Operator in Python
2. Repeat String to a Length With a User-Defined Function in Python

In this tutorial, we will learn the methods to repeat a string n times in Python.

Repeat String N Times With the * Operator in Python

In python, it is very straightforward to repeat a string as many times as we want. We have to use the * operator and specify the number of times we want to repeat the whole string. The code example below shows how to use the * operator to repeat a string n times.

text = "txt" repeated = text * 4 print(repeated) 

In the code above, we created a string variable text , repeated it 4 times, and stored the repeated string inside the new string variable repeated . In the end, we displayed the value of the repeated variable to the user.

This method is convenient when we want to repeat the entire string n times, as shown in the output txttxttxttxt . But if we’re going to repeat a string to a certain length, we have to write our implementation. For example, if the specified length was 10 characters, the above string would look like txttxttxtt .

Repeat String to a Length With a User-Defined Function in Python

The previous method fails if we want to repeat a string but also stay inside a character limit. In python, there is no built-in method for it, so we have to implement our own logic inside a function. The code example below shows how to repeat a string to a certain length with a user-defined function.

def repeat(string_to_repeat, length):  multiple = int(length/len(string_to_repeat) + 1)  repeated_string = string_to_repeat * multiple  return repeated_string[:length]  r = repeat("txt", 10) print(r) 

This time, we have repeated the string txt to length 10 . We wrote the repeat() function that takes the original string string_to_repeat and the length of the repeated string length as input parameters. We then initialized the multiple integer variable that determines how many times the original string needs to be repeated to fit the length limit. This can be determined by dividing the length parameter by the actual length of the string_to_repeat parameter. We added 1 to compensate for the lost values after the decimal point. We then stored a repeating string inside the repeated_string variable by multiplying string_to_repeat with the multiple variable. In the end, we returned the values inside the repeated_string from 0 to the length index.

We used the repeat() function to repeat the string txt to the length 10 and displayed the output. The output shows txttxttxtt , which is what we discussed in the previous section.

Maisam is a highly skilled and motivated Data Scientist. He has over 4 years of experience with Python programming language. He loves solving complex problems and sharing his results on the internet.

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