Getting the length of a string in Python means finding out how many characters make up that string. Getting a string’s length might seem at first like something you could probably do without in computer programming, but it really isn’t.
How to Get the Length of String in Python
Getting a string’s length helps perform several dynamic programming actions. As a side note, bear in mind that Twitter’s entire business runs on being able to get the length of a string.
There are various ways to get the length of a string in Python; below are some of them:
1. Using The Len() Function
The len() function is Python’s built-in means of checking the length of strings and objects, and it is the most straightforward way of going about this task. When we use the len() function on an object or string, it returns the number of characters in that string or object. The way you use the len() function to get a string’s length is as follows:
string = "cloudDevelop" x = len(string)
2. Using The For Loop
We use the for loop for going over each item in a Python sequence, which includes a string. Using the for loop, you can execute a command for each character in a string; here’s the default syntax:
string = "cloudDevelop" for x in string: print(x)
Running the loop above would lead the shell to output each character in the string individually whenever the loop runs. To count the string characters using a for loop, we would create a variable numbered 0 before the loop; then, we set the variable to increment by 1 each time with each run of the loop, then print the variable. Here’s an illustration:
string = "cloudDevelop" length = 0 for x in string: length += 1 print(length)
3. Using While Loop And Slice
The while loop in Python executes a set of commands as long as a defined condition is true. It’s important always to set your condition to be achievable; if not, you would stick your code in an infinite loop. Here’s what a typical while loop looks like:
x = 5 while x >= 1: print(x) x -= 1
To find the length of a string using the while loop, we would also need the slice function, which breaks up a string as you want. The basic syntax of the slice function is as follows:
string[start index:end index]
The start and end index are to be specified; however, if the start index is left empty, it starts from 0, and if the end index is left empty, it starts from the last index. The way we would use a while loop to get the length of a string is as follows:
- Set a counter variable equal to 0 outside the while loop.
- We would set the while condition to be a slice of our string.
- The start index of the slice would be 0, and the end index would be left empty.
- We would increase the counter variable by 1 each time it runs in the while loop.
- Each time the start index is less than the end index, the loop would run.
- We print our number and exit the loop.
Here’s what the code looks like:
string = "cloudDevelop" counter = 0 while string[counter:]: counter += 1 print(counter)
4. Using Lambda, Map And Sum
In Python, a lambda function is a small anonymous function that you can use to run quick expressions. A lambda function takes as many arguments as you want but can only have one expression. The syntax looks like this:
x = lambda arg1, arg2 : arg1 + arg2 print(x(8, 5))
The arguments are between the word “lambda” and the colon, while the expression is everything after the colon.
We use a map() function to execute a function as many times as is specified in an iterable. Therefore, you can put a lambda function in a map function and specify how many times the lambda function runs using a string; like this:
string = "cloudDevelop" map(lambda x : 1 , string)
I’ve just created a map function that creates the number “1” as many times as the number of characters in the string variable.
The map function only outputs an address; we need to wrap it in another function to make its output meaningful. In this case, we would use the sum() function, which adds up every value in an iterable of numbers.
The final code should look like this:
string = "cloudDevelop" print(sum(map(lambda x : 1 , string)))