How to detect any unsupported character other than number

I have series of data in my excel file. But there are some unsupported characters present in the file like 1 0, 0h0,0.>68,1L1 etc. I want to detect all of these using regular expression or any method and replace it by zero. My main moto is detect anything which is not a number and replace it by zero.

Answer 1

[Walter Roberson]

L(L < '0' | L > '9') = '0';

[Aditya]

Can you please clarify your answer

[Walter Roberson]

L is the character string.

The code detects anything that is not a number and replaces it with 0.

The digits are all together as characters, in the order '0' '1' '2' '3' '4' '5' '6' '7' '8' '9' . So anything less than '0' is not a digit and anything greater than '9' is not a digit.