Hello,
I am having trouble writing the code to read a binary string. I would
like to extract the values for use in a calculation.
Any help would be great.
Here is my function that takes in a string.
def parseSequence(data, start):
group_num = data[start:start+2]
element_num = data[start+2:start+4]
vl_field = data[start+4:start+8]
length = struct.unpack('hh', vl_field)[0]
value = data[start+8:(start+8+length)]
pos = start+8+length
element = (group_num+element_num)
if element == '\xfe\xff\x00\xe0':
data = value
while start < length:
group_num = data[start:start+2]
element_num = data[start+2:start+4]
vl_field = data[start+4:start+8]
length = struct.unpack('hh', vl_field)[0]
value = data[start+8:(start+8+length)]
start = start+8+length
element = (group_num+element_num)
if element == '\xfe\xff\x00\xe0':
data = value
while start < length:
group_num = data[start:start+2]
element_num = data[start+2:start+4]
vl_field = data[start+4:start+8]
length = struct.unpack('hh', vl_field)[0]
value = data[start+8:(start+8+length)]
start = start+8+length
element = (group_num+element_num)
return element, start, value
else:
return element, start, value
else:
return element, pos, value
And, here is a sample string (I have split up and indented for
readability). There is an identifier (\xfe\xff\x00\xe0) followed by
the length of the nested values.
'\xfe\xff\x00\xe0\x18\x02\x00\x00 -length=536
\n0q\x00\x02\x00\x00\x001
\n0x\x00\x02\x00\x00\x0010
\n0\x80\x00\x02\x00\x00\x004
\n0\xa0\x00\x02\x00\x00\x000
\x0c0\x04\x00\xe8\x01\x00\x00
\xfe\xff\x00\xe0p\x00\x00\x00 -length=112
\n0\x82\x002\x00\x00\x0042.9068704277562\\-392.3545926477\
\189.182112099444
\n0\x84\x00\x0c\x00\x00\x008.9617062e-1
\n0\x86\x00\x10\x00\x00\x00127.378510918301
\x0c0\x06\x00\x02\x00\x00\x001
\xfe\xff\x00\xe0p\x00\x00\x00 -length=112
\n0\x82\x002\x00\x00\x0042.9068704277562\\-392.3545926477\
\189.182112099444
\n0\x84\x00\x0c\x00\x00\x001.629998e-1
\n0\x86\x00\x10\x00\x00\x0023.159729257873
\x0c0\x06\x00\x02\x00\x00\x004
\xfe\xff\x00\xe0t\x00\x00\x00 -length=116
\n0\x82\x002\x00\x00\x0042.9068704277562\\-392.3545926477\
\189.182112099444
\n0\x84\x00\x10\x00\x00\x001.26285318894435
\n0\x86\x00\x10\x00\x00\x00227.690980638769
\x0c0\x06\x00\x02\x00\x00\x003
\xfe\xff\x00\xe0t\x00\x00\x00 -length=116
\n0\x82\x002\x00\x00\x0042.9068704277562\\-392.3545926477\
\189.182112099444
\n0\x84\x00\x10\x00\x00\x001.52797639111557
\n0\x86\x00\x10\x00\x00\x00263.433384670643
\x0c0\x06\x00\x02\x00\x00\x002 ')
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