I have a binary file and I want to extract all ascii characters while ignoring non-ascii ones. Currently I have:
with open(filename, 'rb') as fobj:
text = fobj.read().decode('utf-16-le')
file = open("text.txt", "w")
file.write("{}".format(text))
file.close
However I'm encountering an error when writing to file UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 0: ordinal not in range(128). How would I get Python to ignore non-ascii?
Use the built-in ASCII codec and tell it to ignore any errors, like:
with open(filename, 'rb') as fobj:
text = fobj.read().decode('utf-16-le')
file = open("text.txt", "w")
file.write("{}".format(text.encode('ascii', 'ignore')))
file.close()
You can test & play around with this in the Python interpreter:
>>> s = u'hello \u00a0 there'
>>> s
u'hello \xa0 there'
Just trying to convert to a string throws an exception.
>>> str(s)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 6: ordinal not in range(128)
...as does just trying to encode that unicode string to ASCII:
>>> s.encode('ascii')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\xa0' in position 6: ordinal not in range(128)
...but telling the codec to ignore the characters it can't handle works okay:
>>> s.encode('ascii', 'ignore')
'hello there'
Basically, the ASCII table takes value in range [0, 27) and associates them to (writable or not) characters. So, to ignore non-ASCII characters, you just have to ignore characters whose code isn't comprise in [0, 27), aka inferior or equal to 127.
In python, there is a function, called ord, which accordingly to the docstring
Return the integer ordinal of a one-character string.
In other words, it gives you the code of a character. Now, you must ignore all characters that, passed to ord, return a value greater than 128. This can be done by:
with open(filename, 'rb') as fobj:
text = fobj.read().decode('utf-16-le')
out_file = open("text.txt", "w")
# Check every single character of `text`
for character in text:
# If it's an ascii character
if ord(character) < 128:
out_file.write(character)
out_file.close
Now, if you just want to conserve printable characters, you must notice that all of them - in the ASCII table at least - are between 32 (space) and 126 (tilde), so you must simply do:
if 32 <= ord(character) <= 126:
ord(char) < 128 and ord(char) > 31?31 < ord(char) < 127 is simpler.
ord(character) <= 126 and ord(character) >= 3232 <= ord(character) <= 126, as that's apparently what she wants anyway. That should be enough change then.if ord(character) >= 32 and ord(character) <= 126... why?