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Read binary from file - Printable Version

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Read binary from file - nextor - Nov-27-2018

I have some trouble reading binary file 



with open('myfile', 'rb') as fl:
    b = fl.read( 1 )
    for x in range( 0,4):
         tuppleCounter[ ( ( 3 << ( x * 2 ) ) & b ) >> ( x*2 ) ]+=1
The interpreter says
TypeError: unsupported operand type(s) for &: 'int' and 'str'

Also
b = int( fl.read( 1 ), 10 )
and
b = int( fl.read( 1 ) )
for both says
ValueError: invalid literal for int() with base 10: 'i'

i dont know what im doing wrong

RE: Read binary from file - Larz60+ - Nov-27-2018

Please post entire error traceback verbatim
supple sample file if possible, or where it can be downloaded
b will read 1 byte, starting at byte number 1 in file
You don't show tuppleCounter
is this what you wanted?

You don't need to supply number base to int if decimal
If I try with random binary file:
>>> with open('image_002.jpg', 'rb') as fp:
...     b = fp.read(1)
... 
>>> b
b'\xff'
>>> for x in range( 0,4):
...     tuppleCounter[ ( ( 3 << ( x * 2 ) ) & b ) >> ( x*2 ) ]+=1
... 
Traceback (most recent call last):
  File "<stdin>", line 2, in <module>
NameError: name 'tuppleCounter' is not defined


RE: Read binary from file - nextor - Nov-27-2018 

if __name__ == "__main__":

    tuppleCounter = [ 0, 0, 0 ,0 ]

    with open('myfile', 'rb') as fl:
        b = fl.read( 1 )

        for x in range( 0,4):
            tuppleCounter[ ( ( 3 << ( x * 2 ) ) & b ) >> ( x*2 ) ]+=1

    print tuppleCounter;

nextor@leon:~/Projects/tmp/pypress$ python test.py
Traceback (most recent call last):
File "test.py", line 10, in <module>
tuppleCounter[ ( ( 3 << ( x * 2 ) ) & b ) >> ( x*2 ) ]+=1
TypeError: unsupported operand type(s) for &: 'int' and 'str'
nextor@leon:~/Projects/tmp/pypress$


RE: Read binary from file - Gribouillis - Nov-27-2018

Are you using PYTHON 2 ?????

RE: Read binary from file - nextor - Nov-27-2018

(Nov-27-2018, 08:45 PM)Gribouillis Wrote: Are you using PYTHON 2 ?????
it says Python 2.7.15+
And with Python 3.6.7rc1 it says the same

RE: Read binary from file - Gribouillis - Nov-27-2018

Python 2 is almost dead (still supported during one year), you should be using python 3.5 or 3.6 or 3.7.
You need to convert the char you read to an int. In python 2, do
b = fl.read(1)
b = ord(b)
In python 3, use
b = fl.read(1)
b = b[0]


RE: Read binary from file - nextor - Nov-27-2018

It works, Thanks Gribouillis