Lucas Oskorep
55 lines
1.9 KiB
Python
55 lines
1.9 KiB
Python
from bitstring import BitArray
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def chunker(seq, size):
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return (seq[pos:pos + size] for pos in range(0, len(seq), size))
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class BinToFloat(object):
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def __init__(self, exponent=8, mantissa=23):
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# self.signed = signed
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self.signed = True
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self.exponent = exponent
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self.mantissa = mantissa
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self.tot_len = exponent + mantissa + (1 if self.signed else 0)
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def process(self, bin_string, reverse_marshalling=False):
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var = BitArray(bin_string)
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chunked_bytes = [x for x in chunker(var, 8)]
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ordered_bytes = []
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for group in reversed(chunked_bytes) if reverse_marshalling else chunked_bytes:
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ordered_bytes.extend(group)
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# ordered_bytes = [x for x in reversed(ordered_bytes)]
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# print(
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# "".join(["1" if x else "0" for x in ordered_bytes[0:1]]),
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# "".join(["1" if x else "0" for x in ordered_bytes[1:1+self.exponent]]),
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# "".join(["1" if x else "0" for x in ordered_bytes[1+self.exponent:1+self.exponent+self.mantissa]])
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# )
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mant = [x for x in reversed(ordered_bytes[:self.mantissa])]
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exp = ordered_bytes[self.mantissa:self.mantissa + self.exponent]
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sign = ordered_bytes[self.mantissa + self.exponent] if self.signed else True
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exp = self.convert_exp(exp)
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mant = self.convert_mantissa(mant)
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val = 2.0 ** exp * mant
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return -val if sign else val
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def convert_exp(self, exp):
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total_val = 0
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digit_val = 1
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for i in exp:
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total_val += digit_val if i else 0
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digit_val *= 2
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tot = (2 ** (self.exponent-1))-1
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# print(tot)
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# print(total_val)
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return total_val - (tot)
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def convert_mantissa(self, mant):
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total_val = 1
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digit_val = .5
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for i in mant:
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total_val += digit_val if i else 0
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digit_val /= 2
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return total_val
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