Filtering Characters from a String
iteration, python, string
Solution
Just use `str.translate()`:
In [4]: 'abcdefabcd'.translate(None, 'acd')
Out[4]: 'befb'
From the documentation:
string.translate(s, table[, deletechars])
Delete all characters from `s` that are in `deletechars` (if present), and then translate the characters using `table`, which must be a 256-character string giving the translation for each character value, indexed by its ordinal. If `table` is None, then only the character deletion step is performed.
If -- for educational purposes -- you'd like to code it up yourself, you could use something like:
''.join(c for c in str1 if c not in str2)
Problem
I need to make a function that takes two strings as imnput and returns a copy of str 1 with all characters from str2 removed. First thing is to iterate over str1 with a for loop, then compare to str2, to accomplish subtraction I should create a 3rd string in which to store the output but I'm a little lost after that. ``` def filter_string(str1, str2): str3 = str1 for character in str1: if character in str2: str3 = str1 - str2 return str3 ``` This is what I've been playing with but I don't understand how I should proceed.