How do I remove ASCII number 13?

Question

I have always wondered why I can\'t replace an unknown whitespace character until just an hour ago that I decided to loop through it and using php ord function I found out that

Answer 1

13 in hexadecimal is 19 in decimal, which is the ASCII control character DC3, which isn't properly whitespace.

You probably mean decimal 13, which is a carriage return. In hexadecimal, that's D, so you'd use \x0D instead.