Hello all,
Fair warning, I didn't know what a bitfield was a few hours ago.
I am working with a program via the dbus module and I am wondering if
there is built-in support to deal with bitfields in Python. I query
my application and it returns a bitfield 119. The bitfield "key" is
NONE = 0,
CAN_GO_NEXT = 1 << 0,
CAN_GO_PREV = 1 << 1,
CAN_PAUSE = 1 << 2,
CAN_PLAY = 1 << 3,
CAN_SEEK = 1 << 4,
CAN_PROVIDE_METADATA = 1 << 5,
CAN_HAS_TRACKLIST = 1 << 6
And a call to the method returns 119. I have gotten far enough to
understand that 119 is
>>> (1<<0)+(1<<1)+(1<<2)+(0<<3)+(1<<4)+(1<<5)+(1<<6)
119
119 is 01110111 as a binary byte (I'm reaching back to high school
computer science here...)
So I guess I understand the basics of what it's telling me, but I'd
like to unpack 119 into binary, so I can read it and use the
information in my program. I've adapted a code snippet that I found
online to do this, but I'm wondering if there is a better way in
python maybe using binascii or struct?
Here is the helper function I've adapated
def int_2_binary(int):
const = 0x80000000
output = ""
## for each bit
for i in range(1,33):
## if the bit is set, print 1
if( int & const ):
output = output + "1"
else:
output = output + "0"
## shift the constant using right shift
const = const >> 1
output = list(output)
output = "".join(output[-8:])
return output
As you can see const is the smallest signed 32-bit integer, and it
would return a length 32 string. But I know that my bitfield will be
8-bit, I just don't know what this is in hexadecimal (?) to define
const. Any pointers to do this in a better way would be appreciated.
Thanks,
Skipper
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