See https://github.com/bitcoin/bips/commits/master/bip-0340 for a list
of contributors. I have obtained permission to do this change from all
contributors in private. Nevertheless, it would be good to get an ACK
from every contributor in order to have publicly available evidence.
- [ ] @sipa
- [ ] @jonasnick
- [ ] @theStack
- [ ] @ysangkok
I haven't contacted @Sajjon and @satsie, whose contributions constitute
of fixing not more than two typos and are thus below the threshold of
originality required for copyright to be applicable.
The `lift_x` function in the BIP and the reference implementation
expect an integer to be passed rather than a byte array.
Can be tested with:
```
$ python3 test-vectors.py > expected.csv
$ diff test-vectors.csv expected.csv
```
bip-0340.mediawiki defines lift_x as taking an integer argument. This commit
changes the argument of lift_x in the reference code to be identical to the
specification. Previously it took a byte array.
This avoids having to update the BIP with a fresh graph every time there's a
change to libsecp and suggests that the expected speedup depends on the specific
implementation.
