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Python 2.7: Printing out an decoded string

I have an file that is called: Abrázame.txt
I want to decode this so that python understands what this 'á' char is so that it will print me Abrázame.txt
This is the following code i have on an Scratch file:
import os
s = os.path.join(r'C:\Test\AutoTest', os.listdir(r'C:\\Test\\AutoTest')[0])
print(unicode(s.decode(encoding='utf-16', errors='strict')))
The error i get from above is:
Traceback (most recent call last):
File "C:/Users/naythan_onfri/.PyCharmCE2017.2/config/scratches/scratch_3.py", line 12, in <module>
print(unicode(s.decode(encoding='utf-16', errors='strict')))
File "C:\Python27\lib\encodings\utf_16.py", line 16, in decode
return codecs.utf_16_decode(input, errors, True)
UnicodeDecodeError: 'utf16' codec can't decode byte 0x74 in position 28: truncated data
I have looked up the utf-16 character set and it does indeed have 'á' character in it. So why is it that this string cannot be decoded with Utf-16.
Also i know that 'latin-1' will work and produce the string im looking for however since this is for an automation project and i wanting to ensure that any filename with any registered character can be decoded and used for other things within the project for example:
"Opening up file explorer at the directory of the file with the file already selected."
Is looping through each of the codecs(Mind you i believe there is 93 codecs) to find whichever one can decode the string, the best way of getting the result I'm looking for? I figure there something far better than that solution.

You want to decode at the edge when you first read a string so that you don't have surprises later in your code. At the edge, you have some reasonable chance of guessing what that encoding is. For this code, the edge is
os.listdir(r'C:\\Test\\AutoTest')[0]
and you can get the current file system directory encoding. So,
import sys
fs_encoding = sys.getfilesystemencoding()
s = os.path.join(r'C:\Test\AutoTest',
os.listdir(r'C:\\Test\\AutoTest')[0].decode(encoding=fs_encodig, errors='strict')
print(s)
Note that once you decode you have a unicode string and you don't need to build a new unicode() object from it.
latin-1 works if that's your current code page. Its an interesting curiosity that even though Windows has supported "wide" characters with "W" versions of their API for many years, python 2 is single-byte character based and doesn't use them.
Long live python 3.

python cleaning high or non-ascii out of a file [duplicate]

I'm working on a series of parsers where I get a bunch of tracebacks from my unit tests like:
File "c:\Python31\lib\encodings\cp1252.py", line 23, in decode
return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 112: character maps to <undefined>
The files are opened with open() with no extra arguemnts. Can I pass extra arguments to open() or use something in the codec module to open these differently?
This came up with code that was written in Python 2 and converted to 3 with the 2to3 tool.
UPDATE: it turns out this is a result of feeding a zipfile into the parser. The unit test actually expects this to happen. The parser should recognize it as something that can't be parsed. So, I need to change my exception handling. In the process of doing that now.

Position 0x81 is unassigned in Windows-1252 (aka cp1252). It is assigned to U+0081 HIGH OCTET PRESET (HOP) control character in Latin-1 (aka ISO 8859-1). I can reproduce your error in Python 3.1 like this:
>>> b'\x81'.decode('cp1252')
Traceback (most recent call last):
...
UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 0: character maps to <undefined>
or with an actual file:
>>> open('test.txt', 'wb').write(b'\x81\n')
2
>>> open('test.txt').read()
Traceback (most recent call last):
...
UnicodeDecodeError: 'utf8' codec can't decode byte 0x81 in position 0: unexpected code byte
Now to treat this file as Latin-1 you pass the encoding argument, like codeape suggested:
>>> open('test.txt', encoding='latin-1').read()
'\x81\n'
Beware that there are differences between Windows-1257 and Latin-1 encodings, e.g. Latin-1 doesn't have “smart quotes”. If the file you're processing is a text file, ask yourself what that \x81 is doing in it.

You can relax the error handling.
For instance:
f = open(filename, encoding="...", errors="replace")
Or:
f = open(filename, encoding="...", errors="ignore")
See the docs.
EDIT:
But are you certain that the problem is in reading the file? Could it be that the exception happens when something is written to the console? Check http://wiki.python.org/moin/PrintFails

All files are "not Unicode". Unicode is an internal representation which must be encoded. You need to determine for each file what encoding has been used, and specify that where necessary when the file is opened.
As the traceback and error message indicate, the file in question is NOT encoded in cp1252.
If it is encoded in latin1, the "\x81" that it is complaining about is a C1 control character that doesn't even have a name (in Unicode). Consider latin1 extremely unlikely to be valid.
You say "some of the files are parsed with xml.dom.minidom" -- parsed successfully or unsuccessfully?
A valid XML file should declare its encoding (default is UTF-8) in the first line, and you should not need to specify an encoding in your code. Show us the code that you are using to do the xml.dom.minidom parsing.
"others read directly as iterables" -- sample code please.
Suggestion: try opening some of each type of file in your browser. Then click View and click Character Encoding (Firefox) or Encoding (Internet Explorer). What encoding has the browser guessed [usually reliably]?
Other possible encoding clues: What languages are used in the text in the files? Where did you get the files from?
Note: please edit your question with clarifying information; don't answer in the comments.

Python3: Why i'm getting a UnicodeDecodeError or is this a Memory issue?

I'm writing a program to iterate my Robocopy-Log (>25 MB). It's by far not ready, cause I'm stuck with a problem.
The problem is that after iterating ~1700 lines of my log -> I get an "UnicodeError":
Traceback (most recent call last):
File "C:/Users/xxxxxx.xxxxxx/SkyDrive/#Python/del_robo2.py", line 6, in <module>
for line in data:
File "C:\Python33\lib\encodings\cp1252.py", line 23, in decode
return codecs.charmap_decode(input,self.errors,decoding_table)[0]
UnicodeDecodeError: 'charmap' codec can't decode byte 0x81 in position 7869: character maps to <undefined>
The program looks as follows:
x="Error"
y=1
arry = []
data = open("Ausstellungen.txt",mode="r")
for line in data:
arry = line.split("\t")
print(y)
y=y+1
if x in arry:
print("found")
print(line)
data.close()
If I reduce the txt file to 1000 lines then the program works.
If I delete line 1500 to 3000 and run again, I get again the unicode error around line 1700.
So have I made an error or is this some memory limiting problem of Python?

Given your data & snippet, I would be surprised if this is a memory issue. It's more likely the encoding: Python is using your system's default encoding to read the file, which is "cp1252" (the default MS Windows encoding), but the file contains byte sequences/bytes which cannot be decoded in that encoding. A candidate for the file's actual encoding might be "latin-1", which you can make Python 3 use by saying
open("Ausstellungen.txt",mode="r", encoding="latin-1")
A possibly similar issue is Python 3 chokes on CP-1252/ANSI reading. A nice talk about the whole thing is here: http://nedbatchelder.com/text/unipain.html

Python decodes all file data to Unicode values. You didn't specify an encoding to use, so Python uses the default for your system, the cp1252 Windows Latin codepage.
However, that is the wrong encoding for your file data. You need to specify an explicit codec to use:
data = open("Ausstellungen.txt",mode="r", encoding='UTF8')
What encoding to use exactly, is unfortunately something you need to figure out yourself. I used UTF-8 as an example codec.
Be aware that some versions of RoboCopy have problems producing valid output.
If you don't yet know what Unicode is, or want to know about encodings, see:
The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!) by Joel Spolsky
The Python Unicode HOWTO
Pragmatic Unicode by Ned Batchelder
The reason you see the error crop up for different parts of your file is that your data contains more than one codepoint that the cp1252 encoding cannot handle.

UnicodeDecodeError

I got an UnicodeDecodeError,
'utf8' codec can't decode byte 0xe5 in position 1923: invalid continuation byte
I have use Danish letter "å" in my template. How can I solve the problem, then I can use non-English letter in my Django project and database?

I can get a similar error (mentioning the same byte value) doing this:
>>> 'å'.encode('latin-1')
b'\xe5'
>>> _.decode('utf-8')
Traceback (most recent call last):
File "<pyshell#18>", line 1, in <module>
_.decode('utf-8')
UnicodeDecodeError: 'utf8' codec can't decode byte 0xe5 in position 0: unexpected end of data
This implies that your data is encoded in latin-1 rather than utf-8. In general, there are two solutions to this: if you have control over your input data, re-save it as UTF-8. Otherwise, when you read the data in Python, set the encoding to latin-1. For a django template, you should be able to use the first - the editor you use should have an 'encoding' option somewhere, change it to utf-8, resave, and everything should work.

this helped me https://stackoverflow.com/a/23278373/2571607
Basically, open C:\Python27\Lib\mimetypes.py
replace
‘default_encoding = sys.getdefaultencoding()’
with
if sys.getdefaultencoding() != 'gbk':
reload(sys)
sys.setdefaultencoding('gbk')
default_encoding = sys.getdefaultencoding()

Python Encoding\Decoding for writing to a text file

I've honestly spent a lot of time on this, and it's slowly killing me. I've stripped content from a PDF and stored it in an array. Now I'm trying to pull it back out of the array and write it into a txt file. However, I do not seem to be able to make it happen because of encoding issues.
allTheNTMs.append(contentRaw[s1:].encode("utf-8"))
for a in range(len(allTheNTMs)):
kmlDescription = allTheNTMs[a]
print kmlDescription #this prints out fine
outputFile.write(kmlDescription)
The error i'm getting is "unicodedecodeerror: ascii codec can't decode byte 0xc2 in position 213:ordinal not in range (128).
I'm just messing around now, but I've tried all kinds of ways to get this stuff to write out.
outputFile.write(kmlDescription).decode('utf-8')
Please forgive me if this is basic, I'm still learning Python (2.7).
Cheers!
EDIT1: Sample data looks something like the following:
Chart 3686 (plan, Morehead City) [ previous update 4997/11 ] NAD83 DATUM
Insert the accompanying block, showing amendments to coastline,
depths and dolphins, centred on: 34° 41´·19N., 76° 40´·43W.
Delete R 34° 43´·16N., 76° 41´·64W.
When I add the print type(raw), I get
Edit 2: When I just try to write the data, I receive the original error message (ascii codec can't decode byte...)
I will check out the suggested thread and video. Thanks folks!
Edit 3: I'm using Python 2.7
Edit 4: agf hit the nail on the head in the comments below when (s)he noticed that I was double encoding. I tried intentionally double encoding a string that had previously been working and produced the same error message that was originally thrown. Something like:
text = "Here's a string, but imagine it has some weird symbols and whatnot in it - apparently latin-1"
textEncoded = text.encode('utf-8')
textEncodedX2 = textEncoded.encode('utf-8')
outputfile.write(textEncoded) #Works!
outputfile.write(textEncodedX2) #failed
Once I figured out I was trying to double encode, the solution was the following:
allTheNTMs.append(contentRaw[s1:].encode("utf-8"))
for a in range(len(allTheNTMs)):
kmlDescription = allTheNTMs[a]
kmlDescriptionDecode = kmlDescription.decode("latin-1")
outputFile.write(kmlDescriptionDecode)
It's working now, and I sure appreciate all of your help!!

My guess is that output file you have opened has been opened with latin1 or even utf-8 codec hence you are not able to write utf-8 encoded data to that because it tries to reconvert it, otherwise to a normally opened file you can write any arbitrary data string, here is an example recreating similar error
u = u'सच्चिदानन्द हीरानन्द वात्स्यायन '
s = u.encode('utf-8')
f = codecs.open('del.text', 'wb',encoding='latin1')
f.write(s)
output:
Traceback (most recent call last):
File "/usr/lib/wingide4.1/src/debug/tserver/_sandbox.py", line 1, in <module>
# Used internally for debug sandbox under external interpreter
File "/usr/lib/python2.7/codecs.py", line 691, in write
return self.writer.write(data)
File "/usr/lib/python2.7/codecs.py", line 351, in write
data, consumed = self.encode(object, self.errors)
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe0 in position 0: ordinal not in range(128)
Solution:
this will work, if you don't set any codec
f = open('del.txt', 'wb')
f.write(s)
other option is to directly write to file without encoding the unicode strings, if outputFile has been opened with correct codec e.g.
f = codecs.open('del.text', 'wb',encoding='utf-8')
f.write(u)

Your error message doesn't seem to appear to relate to any of your Python syntax but actually the fact you're trying to decode a Hex value which has no equivalent in UTF-8.
HEX 0xc2 appears to represent a latin character - an uppercase A with an accent on the top. Therefore, instead of using "allTheNTMs.append(contentRaw[s1:].encode("utf-8"))", try:-
allTheNTMs.append(contentRaw[s1:].encode("latin-1"))
I'm not an expert in Python so this may not work but it would appear you're trying to encode a latin character. Given the error message you are receiving too, it would appear that when trying to encode in UTF-8, Python only looks through the first 128 entries given that your error appears to indicate that entry "0Xc2" is out of range which indeed it is out of the first 128 entries of UTF-8.