Using Python to replace characters in a stringIn this short tutorial, we look at how you could use Python to replace a character in a string. We break down the code to help you understand the function. Show
Table of Contents: Python replace character in string
Unlike lists, Python strings are immutable and hence they cannot be changed once initialized. Because of this, methods used to edit lists cannot be used on a string. However, Python has a few functions that can replace characters in strings. The Python replace() method is used to find and replace characters in a string. It requires a substring to be passed as an argument; the function finds and replaces it. The replace() method is commonly used in data cleaning. However, given strings are immutable, the function replaces characters on a copy of the original string. So ensure you save the new string in case you intend to further use it. Syntax of replace():
Here “string” refers to the string you are looking to replace characters with. Parameter (Python replace character in string):
Code and Explanation:
The above code snippet outputs the following:
As you can see the substring was replaced but the original string still remains the same. Also, given we did not specify a count argument, all the occurrences were replaced. Let us look at a case where we replace multiple instances of a string.
In the above code snippet, we have first replaced “p” only once whereas in the second print statement we have not passed a counter-argument. This means all the occurrences would be replaced. The output is as follows:
Closing thoughts - Python replace character in string:There are other methods that can be used apart from the replace method to replace characters in strings. However, these methods would involve typecasting or slicing, and concatenation. Although these methods work, they are not preferred over the replace() method. However, I would recommend you give them a read and understand the concept. In Python everything is object and string are an object too. Python string can be created simply by enclosing characters in the double quote. For example: var = “Hello World!” In this tutorial, we will learn –
Accessing Values in StringsPython does not support a character type, these are treated as strings of length one, also considered as substring. We use square brackets for slicing along with the index or indices to obtain a substring. var1 = "Guru99!" var2 = "Software Testing" print ("var1[0]:",var1[0]) print ("var2[1:5]:",var2[1:5]) Output var1[0]: G var2[1:5]: oftw Various String OperatorsThere are various string operators that can be used in different ways like concatenating different string. Suppose if a=guru and b=99 then a+b= “guru99”. Similarly, if you are using a*2, it will “GuruGuru”. Likewise, you can use other operators in
string.
Some more examplesYou can update Python String by re-assigning a variable to another string. The new value can be related to previous value or to a completely different string all together. x = "Hello World!" print(x[:6]) print(x[0:6] + "Guru99") Output Hello Hello Guru99 Note : – Slice:6 or 0:6 has the same effect Python String replace() MethodThe method replace() returns a copy of the string in which the values of old string have been replaced with the new value. oldstring = 'I like Guru99' newstring = oldstring.replace('like', 'love') print(newstring) Output I love Guru99 Changing upper and lower case stringsIn Python, you can even change the string to upper case or lower case. string="python at guru99" print(string.upper()) Output PYTHON AT GURU99 Likewise, you can also do for other function as well like capitalize string="python at guru99" print(string.capitalize()) Output Python at guru99 You can also convert your string to lower case string="PYTHON AT GURU99" print(string.lower()) Output python at guru99 Using “join” function for the stringThe join function is a more flexible way for concatenating string. With join function, you can add any character into the string. For example, if you want to add a colon (:) after every character in the string “Python” you can use the following code. print(":".join("Python")) Output P:y:t:h:o:n Reversing StringBy using the reverse function, you can reverse the string. For example, if we have string “12345” and then if you apply the code for the reverse function as shown below. string="12345" print(''.join(reversed(string))) Output 54321 Split strings is another function that can be applied in Python let see for string “guru99 career guru99”. First here we will split the string by using the command word.split and get the result. word="guru99 career guru99" print(word.split(' ')) Output ['guru99', 'career', 'guru99'] To understand this better we will see one more example of split, instead of space (‘ ‘) we will replace it with (‘r’) and it will split the string wherever ‘r’ is mentioned in the string word="guru99 career guru99" print(word.split('r')) Output ['gu', 'u99 ca', 'ee', ' gu', 'u99'] Important Note: In Python, Strings are immutable. Consider the following code x = "Guru99" x.replace("Guru99","Python") print(x) Output Guru99 will still return Guru99. This is because x.replace(“Guru99″,”Python”) returns a copy of X with replacements made You will need to use the following code to observe changes x = "Guru99" x = x.replace("Guru99","Python") print(x) Output Python Above codes are Python 3 examples, If you want to run in Python 2 please consider following code. Python 2 Example #Accessing Values in Strings var1 = "Guru99!" var2 = "Software Testing" print "var1[0]:",var1[0] print "var2[1:5]:",var2[1:5] #Some more examples x = "Hello World!" print x[:6] print x[0:6] + "Guru99" #Python String replace() Method oldstring = 'I like Guru99' newstring = oldstring.replace('like', 'love') print newstring #Changing upper and lower case strings string="python at guru99" print string.upper() string="python at guru99" print string.capitalize() string="PYTHON AT GURU99" print string.lower() #Using "join" function for the string print":".join("Python") #Reversing String string="12345" print''.join(reversed(string)) #Split Strings word="guru99 career guru99" print word.split(' ') word="guru99 career guru99" print word.split('r') x = "Guru99" x.replace("Guru99","Python") print x x = "Guru99" x = x.replace("Guru99","Python") print x Output var1[0]: G var2[1:5]: oftw Hello Hello Guru99 I love Guru99 PYTHON AT GURU99 Python at guru99 python at guru99 P:y:t:h:o:n 54321 ['guru99', 'career', 'guru99'] ['gu', 'u99 ca', 'ee', ' gu', 'u99'] Guru99 Python Python has introduced a .format function which does way with using the cumbersome %d and so on for string formatting. » Learn more about Python String split() Summary:Since Python is an object-oriented programming language, many functions can be applied to Python objects. A notable feature of Python is its indenting source statements to make the code easier to read.
How do you replace multiple characters in a string in Python?Replace Multiple Characters in a String in Python. Use str.replace() to Replace Multiple Characters in Python.. Use re.sub() or re.subn() to Replace Multiple Characters in Python.. translate() and maketrans() to Replace Multiple Characters in Python.. How do you change a range of a string in Python?Below are 6 common methods used to replace the character in strings while programming in python.. 1) Using slicing method.. 2) Using replace() method.. 3) Using the list data structure.. 4) Replace multiple characters with the same character.. 5) Replace multiple characters with different characters.. 6) Using regex module.. How do you replace certain letters in Python?The Python replace() method is used to find and replace characters in a string. It requires a substring to be passed as an argument; the function finds and replaces it. The replace() method is commonly used in data cleaning.
How do you replace a character in a specific position in a string in Python?Strings in Python are immutable meaning you cannot replace parts of them. You can however create a new string that is modified. Mind that this is not semantically equivalent since other references to the old string will not be updated.
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