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Python 2.7 with pandas to_csv() gives UnicodeEncodeError: 'ascii' codec can't encode character u'\xc7' in position 4: ordinal not in range(128)

I am using Python 2.7, and to overcome UTF-8 issues, I am using pandas to_csv method. The issue is, I am still getting unicode errors, which I dont get when I run the script on my local laptop with python 3 (not an option for batch processing).
df = pd.DataFrame(stats_results)
df.to_csv('/home/mp9293q/python_scripts/stats_dim_registration_set_column_transpose.csv', quoting=csv.QUOTE_ALL, doublequote=True, index=False,
index_label=False, header=False, line_terminator='\n', encoding='utf-8');
Gives error:
UnicodeEncodeError: 'ascii' codec can't encode character u'\xc7' in position 4: ordinal not in range(128)

I believe you might be having one of these two problems (or maybe both):-
As you mentioned in the comments, the file in which you are trying
to save Unicode Data, already exists. Then there are quite
likely chances that the destination file, may not have
UTF-8/16/32 as it encoding scheme.
By this I mean, when the file was originally created, it's encoding
scheme may not be UTF-8, it could possibly be ANSI. So,
check whether the destination file's encoding scheme is of UTF
family or not.
Encode the Unicode string to UTF-8,
before storing it in a file. By this I mean, any content that you
are trying to save to your destination file, if contains Unicode
text, then it should be first encoded.
Ex.
# A character which could not be encoded via 8 bit ASCII
Uni_str = u"Ç"
# Converting the unicode text, into UTF-8 format
Uni_str = Uni_str.encode("utf-8")
The above code works differently in python 2.x and 3.x, the reason
being that 2.x uses ASCII as default encoding scheme, and 3.x uses
UTF-8. Another difference between the two is how they treat a string
after passing it via encode().
In Python 2.x
type(u"Ç".encode("utf-8"))
Outputs
<type 'str'>
In Python 3.x
type(u"Ç".encode("utf-8"))
Outputs
<class 'bytes'>
As you can notice, in python 2.x the return type of encode() is
string, but in 3.x it is bytes.
So for your case, I would recommend you to encode each string value containing unicode data in your dataframe using encode() before trying to store it in the file.

Python3, issues using ctf-8 encode/decode (on some ocassions)

So, I'm having issues with Python3 encoding. I have a few bytes I want to work as strings. (long story)
In few words, this works
a = "\x85".encode()
print(a.decode())
But this doesn't
b = (0x85).to_bytes(1,"big")
print(b.decode())
UnicodeDecodeError: utf-8 codec can't decode byte 0x85 in position 0:
invalid start byte
I have read a handful of articles on the subject, but they insist that 'python3 is broken' or that 'you shouldn't be using strings for that'. Plenty articles on Stackoverflow just use "work arounds" (such as "use replace on error" or "user utc-16").
Could anyone tell me where the difference lies and why the function works while the second one doesn't? Shouldn't both of them work identically? Why can't utf-8 decode the byte on the second attempt?

In the first case '\x85'.encode() encodes the Unicode code point U+0085 in the Python 3 default encoding of UTF-8. So the output is the correct two-byte UTF-8 encoding of that code point:
>>> '\x85'.encode()
b'\xc2\x85'
Decode then works because it was correctly encoded in UTF-8 to begin with:
>>> b'\xc2\x85'.decode()
'\x85'
The second case is a complicated way of creating a single byte string:
>>> (0x85).to_bytes(1,'big')
b'\x85'
This byte string is not correctly encoded as UTF-8, so it fails to decode:
>>> b'\x85'.decode()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'utf-8' codec can't decode byte 0x85 in position 0: invalid start byte
Python 3 is definitely not "broken". It cleanly separates byte data from text.
If you have raw bytes, work with them as bytes. Raw data in Python 3 is intended to be manipulated in byte strings or byte arrays. Unicode strings are for text. Decode bytes to text to manipulate it, then encode back to bytes to serialize to file, socket, database, etc.
If for some reason you feel the need to use Unicode strings for raw data, the first 256 code points of Unicode correspond to the latin1 codec for 1:1 mapping of one to the other.
>>> '\x85'.encode('latin1')
b'\x85'
>>> b'\x85'.decode('latin1')
'\x85'
This is often used to correct programming errors due to encoding/decoding with the wrong encodings.

Python3 using UTF-8 data from bytes [duplicate]

Why is the below item failing? Why does it succeed with "latin-1" codec?
o = "a test of \xe9 char" #I want this to remain a string as this is what I am receiving
v = o.decode("utf-8")
Which results in:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "C:\Python27\lib\encodings\utf_8.py",
line 16, in decode
return codecs.utf_8_decode(input, errors, True) UnicodeDecodeError:
'utf8' codec can't decode byte 0xe9 in position 10: invalid continuation byte

I had the same error when I tried to open a CSV file by pandas.read_csv
method.
The solution was change the encoding to latin-1:
pd.read_csv('ml-100k/u.item', sep='|', names=m_cols , encoding='latin-1')

In binary, 0xE9 looks like 1110 1001. If you read about UTF-8 on Wikipedia, you’ll see that such a byte must be followed by two of the form 10xx xxxx. So, for example:
>>> b'\xe9\x80\x80'.decode('utf-8')
u'\u9000'
But that’s just the mechanical cause of the exception. In this case, you have a string that is almost certainly encoded in latin 1. You can see how UTF-8 and latin 1 look different:
>>> u'\xe9'.encode('utf-8')
b'\xc3\xa9'
>>> u'\xe9'.encode('latin-1')
b'\xe9'
(Note, I'm using a mix of Python 2 and 3 representation here. The input is valid in any version of Python, but your Python interpreter is unlikely to actually show both unicode and byte strings in this way.)

It is invalid UTF-8. That character is the e-acute character in ISO-Latin1, which is why it succeeds with that codeset.
If you don't know the codeset you're receiving strings in, you're in a bit of trouble. It would be best if a single codeset (hopefully UTF-8) would be chosen for your protocol/application and then you'd just reject ones that didn't decode.
If you can't do that, you'll need heuristics.

Because UTF-8 is multibyte and there is no char corresponding to your combination of \xe9 plus following space.
Why should it succeed in both utf-8 and latin-1?
Here how the same sentence should be in utf-8:
>>> o.decode('latin-1').encode("utf-8")
'a test of \xc3\xa9 char'

If this error arises when manipulating a file that was just opened, check to see if you opened it in 'rb' mode

Use this, If it shows the error of UTF-8
pd.read_csv('File_name.csv',encoding='latin-1')

utf-8 code error usually comes when the range of numeric values exceeding 0 to 127.
the reason to raise this exception is:
1)If the code point is < 128, each byte is the same as the value of the code point.
2)If the code point is 128 or greater, the Unicode string can’t be represented in this encoding. (Python raises a UnicodeEncodeError exception in this case.)
In order to to overcome this we have a set of encodings, the most widely used is "Latin-1, also known as ISO-8859-1"
So ISO-8859-1 Unicode points 0–255 are identical to the Latin-1 values, so converting to this encoding simply requires converting code points to byte values; if a code point larger than 255 is encountered, the string can’t be encoded into Latin-1
when this exception occurs when you are trying to load a data set ,try using this format
df=pd.read_csv("top50.csv",encoding='ISO-8859-1')
Add encoding technique at the end of the syntax which then accepts to load the data set.

Well this type of error comes when u are taking input a particular file or data in pandas such as :-
data=pd.read_csv('/kaggle/input/fertilizers-by-product-fao/FertilizersProduct.csv)
Then the error is displaying like this :-
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xf4 in position 1: invalid continuation byte
So to avoid this type of error can be removed by adding an argument
data=pd.read_csv('/kaggle/input/fertilizers-by-product-fao/FertilizersProduct.csv', encoding='ISO-8859-1')

This happened to me also, while i was reading text containing Hebrew from a .txt file.
I clicked: file -> save as and I saved this file as a UTF-8 encoding

TLDR: I would recommend investigating the source of the problem in depth before switching encoders to silence the error.
I got this error as I was processing a large number of zip files with additional zip files in them.
My workflow was the following:
Read zip
Read child zip
Read text from child zip
At some point I was hitting the encoding error above. Upon closer inspection, it turned out that some child zips erroneously contained further zips. Reading these zips as text lead to some funky character representation that I could silence with encoding="latin-1", but which in turn caused issues further down the line. Since I was working with international data it was not completely foolish to assume it was an encoding problem (I had problems with 0xc2: Â), but in the end it was not the actual issue.

In this case, I tried to execute a .py which active a path/file.sql.
My solution was to modify the codification of the file.sql to "UTF-8 without BOM" and it works!
You can do it with Notepad++.
i will leave a part of my code.
con = psycopg2.connect(host = sys.argv[1],
port = sys.argv[2],dbname = sys.argv[3],user = sys.argv[4], password = sys.argv[5])
cursor = con.cursor()
sqlfile = open(path, 'r')

I encountered this problem, and it turned out that I had saved my CSV directly from a google sheets file. In other words, I was in a google sheet file. I chose, save a copy, and then when my browser downloaded it, I chose Open. Then, I DIRECTLY saved the CSV. This was the wrong move.
What fixed it for me was first saving the sheet as an .xlsx file on my local computer, and from there exporting single sheet as .csv. Then the error went away for pd.read_csv('myfile.csv')

The solution was change to "UTF-8 sin BOM"

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.

UnicodeDecodeError during encode?

We're running into a problem (which is described http://wiki.python.org/moin/UnicodeDecodeError) -- read the second paragraph '...Paradoxically...'.
Specifically, we're trying to up-convert a string to unicode and we are receiving a UnicodeDecodeError.
Example:
>>> unicode('\xab')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xab in position 0: ordinal not in range(128)
But of course, this works without any problems
>>> unicode(u'\xab')
u'\xab'
Of course, this code is to demonstrate the conversion problem. In our actual code, we are not using string literals and we can cannot just pre-pend the unicode 'u' prefix, but instead we are dealing with strings returned from an os.walk(), and the file name includes the above value. Since we cannot coerce the value to a unicode without calling unicode() constructor, we're not sure how to proceed.
One really horrible hack that occurs is to write our own str2uni() method, something like:
def str2uni(val):
r"""brute force coersion of str -> unicode"""
try:
return unicode(src)
except UnicodeDecodeError:
pass
res = u''
for ch in val:
res += unichr(ord(ch))
return res
But before we do this -- wanted to see if anyone else had any insight?
UPDATED
I see everyone is getting focused on HOW I got to the example I posted, rather than the result. Sigh -- ok, here's the code that caused me to spend hours reducing the problem to the simplest form I shared above.
for _,_,files in os.walk('/path/to/folder'):
for fname in files:
filename = unicode(fname)
That piece of code tosses a UnicodeDecodeError exception when the filename has the following value '3\xab Floppy (A).link'
To see the error for yourself, do the following:
>>> unicode('3\xab Floppy (A).link')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeDecodeError: 'ascii' codec can't decode byte 0xab in position 1: ordinal not in range(128)
UPDATED
I really appreciate everyone trying to help. And I also appreciate that most people make some pretty simple mistakes related to string/unicode handling. But I'd like to underline the reference to the UnicodeDecodeError exception. We are getting this when calling the unicode() constructor!!!
I believe the underlying cause is described in the aforementioned Wiki article http://wiki.python.org/moin/UnicodeDecodeError. Read from the second paragraph on down about how "Paradoxically, a UnicodeDecodeError may happen when encoding...". The Wiki article very accurately describes what we are experiencing -- but while it elaborates on the cuases, it makes no suggestions for resolutions.
As a matter of fact, the third paragraph starts with the following astounding admission "Unlike a similar case with UnicodeEncodeError, such a failure cannot be always avoided...".
Since I am not used to "cant get there from here" information as a developer, I thought it would be interested to cast about on Stack Overflow for the experiences of others.

I think you're confusing Unicode strings and Unicode encodings (like UTF-8).
os.walk(".") returns the filenames (and directory names etc.) as strings that are encoded in the current codepage. It will silently remove characters that are not present in your current codepage (see this question for a striking example).
Therefore, if your file/directory names contain characters outside of your encoding's range, then you definitely need to use a Unicode string to specify the starting directory, for example by calling os.walk(u"."). Then you don't need to (and shouldn't) call unicode() on the results any longer, because they already are Unicode strings.
If you don't do this, you first need to decode the filenames (as in mystring.decode("cp850")) which will give you a Unicode string:
>>> "\xab".decode("cp850")
u'\xbd'
Then you can encode that into UTF-8 or any other encoding.
>>> _.encode("utf-8")
'\xc2\xbd'
If you're still confused why unicode("\xab") throws a decoding error, maybe the following explanation helps:
"\xab" is an encoded string. Python has no way of knowing which encoding that is, but before you can convert it to Unicode, it needs to be decoded first. Without any specification from you, unicode() assumes that it is encoded in ASCII, and when it tries to decode it under this assumption, it fails because \xab isn't part of ASCII. So either you need to find out which encoding is being used by your filesystem and call unicode("\xab", encoding="cp850") or whatever, or start with Unicode strings in the first place.

for fname in files:
filename = unicode(fname)
The second line will complaint if fname is not ASCII. If you want to convert the string to Unicode, instead of unicode(fname) you should do fname.decode('<the encoding here>').
I would suggest the encoding but you don't tell us what does \xab is in your .link file. You can search in google for the encoding anyways so it would stay like this:
for fname in files:
filename = fname.decode('<encoding>')
UPDATE: For example, IF the encoding of your filesystem's names is ISO-8859-1 then \xab char would be "«". To read it into python you should do:
for fname in files:
filename = fname.decode('latin1') #which is synonym to #ISO-8859-1
Hope this helps!

As I understand it your issue is that os.walk(unicode_path) fails to decode some filenames to Unicode. This problem is fixed in Python 3.1+ (see PEP 383: Non-decodable Bytes in System Character Interfaces):
File names, environment variables, and command line arguments are
defined as being character data in POSIX; the C APIs however allow
passing arbitrary bytes - whether these conform to a certain encoding
or not. This PEP proposes a means of dealing with such irregularities
by embedding the bytes in character strings in such a way that allows
recreation of the original byte string.
Windows provides Unicode API to access filesystem so there shouldn't be this problem.
Python 2.7 (utf-8 filesystem on Linux):
>>> import os
>>> list(os.walk("."))
[('.', [], ['\xc3('])]
>>> list(os.walk(u"."))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python2.7/os.py", line 284, in walk
if isdir(join(top, name)):
File "/usr/lib/python2.7/posixpath.py", line 71, in join
path += '/' + b
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 1: \
ordinal not in range(128)
Python 3.3:
>>> import os
>>> list(os.walk(b'.'))
[(b'.', [], [b'\xc3('])]
>>> list(os.walk(u'.'))
[('.', [], ['\udcc3('])]
Your str2uni() function tries (it introduces ambiguous names) to solve the same issue as "surrogateescape" error handler on Python 3. Use bytestrings for filenames on Python 2 if you are expecting filenames that can't be decoded using sys.getfilesystemencoding().

'\xab'
Is a byte, number 171.
u'\xab'
Is a character, U+00AB Left-pointing double angle quotation mark («).
u'\xab' is a short-hand way of saying u'\u00ab'. It's not the same (not even the same datatype) as the byte '\xab'; it would probably have been clearer to always use the \u syntax in Unicode string literals IMO, but it's too late to fix that now.
To go from bytes to characters is known as a decode operation. To go from characters to bytes is known as an encode operation. For either direction, you need to know which encoding is used to map between the two.
>>> unicode('\xab')
UnicodeDecodeError
unicode is a character string, so there is an implicit decode operation when you pass bytes to the unicode() constructor. If you don't tell it which encoding you want you get the default encoding which is often ascii. ASCII doesn't have a meaning for byte 171 so you get an error.
>>> unicode(u'\xab')
u'\xab'
Since u'\xab' (or u'\u00ab') is already a character string, there is no implicit conversion in passing it to the unicode() constructor - you get an unchanged copy.
res = u''
for ch in val:
res += unichr(ord(ch))
return res
The encoding that maps each input byte to the Unicode character with the same ordinal value is ISO-8859-1. Consequently you could replace this loop with just:
return unicode(val, 'iso-8859-1')
(However note that if Windows is in the mix, then the encoding you want is probably not that one but the somewhat-similar windows-1252.)
One really horrible hack that occurs is to write our own str2uni() method
This isn't generally a good idea. UnicodeErrors are Python telling you you've misunderstood something about string types; ignoring that error instead of fixing it at source means you're more likely to hide subtle failures that will bite you later.
filename = unicode(fname)
So this would be better replaced with: filename = unicode(fname, 'iso-8859-1') if you know your filesystem is using ISO-8859-1 filenames. If your system locales are set up correctly then it should be possible to find out the encoding your filesystem is using, and go straight to that:
filename = unicode(fname, sys.getfilesystemencoding())
Though actually if it is set up correctly, you can skip all the encode/decode fuss by asking Python to treat filesystem paths as native Unicode instead of byte strings. You do that by passing a Unicode character string into the os filename interfaces:
for _,_,files in os.walk(u'/path/to/folder'): # note u'' string
for fname in files:
filename = fname # nothing more to do!
PS. The character in 3″ Floppy should really be U+2033 Double Prime, but there is no encoding for that in ISO-8859-1. Better in the long term to use UTF-8 filesystem encoding so you can include any character.