100 lines
2.4 KiB
Python
100 lines
2.4 KiB
Python
#!/usr/bin/env python
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# -*- coding: utf-8 -*-
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"""
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Generates latex tables for hamming codes
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(C) 2022 Louis Heredero louis.heredero@edu.vs.ch
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"""
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start = r""" \begin{tabu}{|[2pt]c|c|c|c|c|c|c|c|[2pt]}
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\tabucline[2pt]{-}
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& 1 & 2 & 3 & 4 & 5 & 6 & 7 \\
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\tabucline[1pt]{-}
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"""
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end = r""" \tabucline[2pt]{-}
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\end{tabu}
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"""
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class HammingError(Exception):
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pass
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def encode(data, blocksize=7):
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A = start
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B = start
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result = []
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datasize = blocksize-blocksize.bit_length()
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data = list(map(int, data))
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if len(data) % datasize:
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raise HammingError(f"Length of data is not a multiple of {datasize}")
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nblocks = int(len(data)/datasize)
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last = 0
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for b in range(nblocks):
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if b > 0:
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A += " \\hline\n"
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B += " \\hline\n"
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A += f" Group {b+1}"
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B += f" Group {b+1}"
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count = 0
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for i in range(blocksize):
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A += " & "
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count += data[0]
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# Power of 2
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if (i+1)&i == 0 or i == 0:
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A += "\_"
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result.append(0)
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else:
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A += str(data[0])
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result.append(data.pop(0))
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A += " \\\\\n"
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for i in range(blocksize.bit_length()):
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p = 1 << i
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c = sum([result[b*blocksize+j] for j in range(blocksize) if (j+1)&p])
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if c%2:
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result[b*blocksize+p-1] = 1
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for i in range(blocksize):
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B += " & "
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B += str(result[b*blocksize+i])
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B += " \\\\\n"
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if count == 0:
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if last >= 2:
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A = A.rsplit("\n",2)[0]
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A += "\n ... & ... & ... & ... & ... & ... & ... & ... \\\\\n"
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B = B.rsplit("\n",2)[0]
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B += "\n ... & ... & ... & ... & ... & ... & ... & ... \\\\\n"
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break
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last += 1
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else:
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last = 0
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#return "".join(list(map(str, result)))
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A += end
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B += end
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return A, B
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if __name__ == "__main__":
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data = "00000000001111101011000010100110101100111"
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ds = 4
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total_bits = (3**2 * 24 - 6)
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data_bits = total_bits * ds // 7
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data += "0"*(ds-len(data)%ds)
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s = ""
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i = 0
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left = data_bits-len(data)
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while len(s) < left:
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s += f"{i:0b}"
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i += 1
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s = s[:left]
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data += s
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a, b = encode(data)
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print(a)
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print(b)
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