bbchallenge's undecided index

The goal of https://bbchallenge.org/ is to decided the behavior of all 5-state Turing machine (from all-0 tape), see Story.

We do so by writing deciders, which are programs that decide machines.

The machines that have not yet be decided by any decider are compiled in the index bb5_undecided_index stored in this repository. See undecided machines index file.

This file is a binary file containing a sorted succession of big-endian uint32 (4-byte). Each of these integers is the index of an undecided machine in the seed database. See https://github.com/bbchallenge/bbchallenge-seed.

Why on github?

By definition, this index file is meant to evolve thanks to new deciders being coded and hopefully reach a size of 0 when all the machines are decided.

Note also that sometimes we discover bugs in already applied deciders hence we may want to restore the index to a precedent version.

This is why using git is handy as we can keep track of each index's version and backtrack if needed.

Reading the index

Here are some routines to help you reading the index:

Python

def get_indices_from_index_file(index_file_path):
  index_file_size = os.path.getsize(index_file_path)

  machines_indices = []
  with open(index_file_path, "rb") as f:
    for i in range(index_file_size//4):
      chunk = f.read(4)
      machines_indices.append(int.from_bytes(chunk, byteorder="big"))

  return machines_indices

Go

func GetIndicesFromIndexFile(indexFilePath string) (
 machinesIndices []uint32, err error) {

 var rawIndex []byte
 rawIndex, err = ioutil.ReadFile(indexFilePath)

 if err != nil {
   return machinesIndices, err
 }

 for i := 0; i < len(rawIndex)/4; i += 4 {
   machinesIndices = append(
   machinesIndices, binary.BigEndian.Uint32(rawIndex[i:i+4]))
 }

 return machinesIndices, err
}

License

This data is licensed under a Creative Commons Attribution 4.0 International License.

You should have received a copy of the license along with this work. If not, see http://creativecommons.org/licenses/by/4.0/.