How to extract digits from a string? (extract numbers from text)

In this article we will learn how to extract digits from a string – thus being able to separate numbers from other characters of any text in Python

What’s up programmer, ok? Let’s learn how to manipulate strings in Python and separate the numbers from it!

In Python we have the possibility to traverse a string as if it were a list, that is, character by character with a loop

See this example:

text = "9a3b4c5x"

for letter in text:
 print(letter)

We will have the following return:

9
a
3
b
4
c
5
x

Now that we have a way to check each character we just need to validate if it is a digit

And then separate them into a list or do whatever other logic is needed in your software

Let’s implement this check:

text = "9a3b4c5x"
onlyDigits = []

for char in text:
 if char.isdigit():
  onlyDigits.append(char)

print(onlyDigits)

Now the validation done by isdigit() checks whether the character is a digit or not

Then we insert only the digits in the list through the append method

See the end result:

['9', '3', '4', '5']

That way we can separate the digits of a string!

Conclusion

In this article we learned how to extract digits from a string

We submit a string to a “loop for” to iterate through each character in it.

Then we apply a check to see if the character is a digit, finally we add the digits to a list with the append method

Do you want to learn more about Python? Click here!