Table of Contents
How to copy string in Python?
Today, we are going to discuss strings in python. We will discuss strings, how to manipulate strings using python, how to copy strings, etc.
So, let’s start with the basic intuition of strings. Strings are basically an array. Characters are arranged in a string. In Python, a string is anything enclosed in quotations. Additionally, you can use single or double quotations. For instance: message = "This is a Python string." This is also a string, the message says.
Website = 'GoLinuxCloud'
Programming_language = "Python"We can define strings using a single quotation or double quotation as shown in the above code snippet. Before discussing the many ways to copy a string in Python, it is essential to remember that a string cannot be duplicated and copied directly. Strings in Python are permanent, which means that their value cannot change while the program is running. Because strings are immutable, they cannot be copied directly.
You may think that we can copy the strings as shown below:
website = 'GoLinuxCloud'
copy = website
print(copy)Output:
GoLinuxCloud
We have declared a variable website and assigned it a string value, we have declared another variable called copy and we assigned the value of website to it. In this case, we are actually not copying the string, This would not duplicate the initial string. Instead, the same string would be referenced by both newly formed variables.
In this article, we are discussing how we can copy a string, there are some ways where you can easily copy the string value. Let’s discuss this one by one.
Method-1: Using an empty string to copy a string
We can copy a string value from one variable to another variable by using an empty string. The empty string will be concatenated with the actual string that we are copying. To do this, we must declare the new string and use the concatenation operator (+) to join the new string to the original string. We will take the above example to understand this very well.
Example: copying a string using an empty string in python
website = 'GoLinuxCloud'
copy = '' + website
print(copy)Output:
GoLinuxCloud
In the code snippet above, we are copying a string from a variable website to another variable called copy, As you can see that we have initialized an empty string using two single quotes (‘’) and we are using the concatenation operator (+) to combine the empty string with the actual string. This way, we are copying the whole string value from one variable to another.
Method-2: Using slicing to copy a string
In Python, we can use slicing to slice the sequence of strings. The slicing function returns the sliced object, the best thing about slicing in python is that we can specify from where to start slicing the sequence and where to stop. We can use the slice() function and slice operator (:). To slice the original string and create a new one, use the slice or the (:) operator. The syntax of the slicing operator requires a start value and an index value. The old string would be transferred unchanged to the new variable if neither of these values is given.
Example: copying a string using slicing in python
Have a look at the code below where slicing is used to copy the string from one variable to another.
website = 'GoLinuxCloud'
copy = website[:]
print(copy)Output:
GoLinuxCloud
We are not giving any starting point and ending, so the (:) will copy the whole string from the first variable to the second one. Let’s understand this better by giving starting and ending points.
website = 'GoLinuxCloud'
copy = website[0:2]
print(copy)Output:
Go
We are now giving a starting point and the ending point to copy the string. The slicer will now take the first two characters from the string and copy them to the next variable.
website = 'GoLinuxCloud'
copy = website[2:7]
print(copy)Output:
Linux
Here, we are giving the starting point 2 which means that it will miss the first two characters and copy up to the 7 characters.
Method-3: Using str() to copy a string
There is a very well know built-in function in python which is the str() function. This function takes a string as a parameter and returns the original string as the copy. So this function can also be used to copy a string. Let’s see an example using the str() function.
Example: copying a string using str()
website = 'GoLinuxCloud'
copy = str(website)
print(copy)Output:
GoLinuxCloud
Wow! The str() function is very easy to use and it copied the string from one variable to another. But str() returns the copy of a string as a whole. If you want to copy some of the characters from the string then slicing is the best way.
That’s all for today. Stay connected.
Thank you!
Summary
Today, we discussed how you can copy a string from one variable to another variable. You cannot directly copy a string by assigning the string variable next to another, it will not copy the string but reference it only. We discussed some other ways which can be used to copy the original string.
Further Reading
How can I copy a Python string? - Stack Overflow
