64 lines
2.1 KiB
Python
64 lines
2.1 KiB
Python
from .consts import OFFSET
|
|
|
|
def bytes_to_unicode_original():
|
|
# Can call this through
|
|
# from transformers.models.gpt2.tokenization_gpt2 import bytes_to_unicode
|
|
"""
|
|
Returns list of utf-8 byte and a mapping to unicode strings. We specifically avoids mapping to whitespace/control
|
|
characters the bpe code barfs on.
|
|
|
|
The reversible bpe codes work on unicode strings. This means you need a large # of unicode characters in your vocab
|
|
if you want to avoid UNKs. When you're at something like a 10B token dataset you end up needing around 5K for
|
|
decent coverage. This is a significant percentage of your normal, say, 32K bpe vocab. To avoid that, we want lookup
|
|
tables between utf-8 bytes and unicode strings.
|
|
"""
|
|
bs = (
|
|
list(range(ord("!"), ord("~") + 1)) + list(range(ord("¡"), ord("¬") + 1)) + list(range(ord("®"), ord("ÿ") + 1))
|
|
)
|
|
cs = bs[:]
|
|
n = 0
|
|
for b in range(2**8):
|
|
if b not in bs:
|
|
bs.append(b)
|
|
cs.append(2**8 + n)
|
|
n += 1
|
|
cs = [chr(n) for n in cs]
|
|
return dict(zip(bs, cs))
|
|
|
|
def bytes_to_unicode_special(special_bytes, offset=OFFSET):
|
|
bs = (
|
|
list(range(ord("!"), ord("~") + 1)) + list(range(ord("¡"), ord("¬") + 1)) + list(range(ord("®"), ord("ÿ") + 1))
|
|
)
|
|
cs = bs[:]
|
|
n = 0
|
|
for b in range(2**8):
|
|
if b not in bs:
|
|
bs.append(b)
|
|
cs.append(2**8 + n)
|
|
n += 1
|
|
|
|
for b in special_bytes:
|
|
bs.append(offset+b)
|
|
cs.append(2**8 + n)
|
|
n += 1
|
|
|
|
cs = [chr(n) for n in cs]
|
|
return dict(zip(bs, cs))
|
|
|
|
byte2unic = bytes_to_unicode_original()
|
|
unic2byte = {value: key for key, value in byte2unic.items()}
|
|
|
|
def decode_uniced(scrambled):
|
|
unic_nums = [unic2byte[a] for a in scrambled]
|
|
char_byte = [chr(a) for a in unic_nums]
|
|
full = "".join(char_byte)
|
|
return full.encode("latin-1").decode()
|
|
|
|
|
|
def find_aether_bytes(encoding, range_start, range_end):
|
|
aether_bytes = set()
|
|
for i in range(range_start, range_end):
|
|
pieces = chr(i).encode(encoding)
|
|
for piece in pieces:
|
|
aether_bytes.add(piece)
|
|
return aether_bytes |