ATOM 99998 SD MET L9999 48.231 -64.383 -9.257 1.00 11.54 S ATOM 99999 CE MET L9999 49.398 -63.242 -10.211 1.00 14.60 C ATOM A0000 N VAL LA000 52.228 -67.689 -12.196 1.00 8.76 N ATOM A0001 CA VAL LA000 53.657 -67.774 -12.458 1.00 3.40 C
The hybrid-36 counting system accommodates up to 87440031 ATOM serial numbers and up to 2436111 residue sequence numbers per chain. With the hybrid-36 system the distinction between "traditional" and "extended" PDB files becomes evident only if there are more than 99999 atoms to be stored.
Programs that are updated to support the hybrid-36 system will continue to interoperate with programs that do not as long as there are less than 100000 atoms. Updating existing programs to support the hybrid-36 system requires very little effort since the decoded numbers are still stored as 4-byte integers. The only change is to replace a few "normal" read and write statements with calls of the hy36decode() and hy36encode() functions.
All implementations have NO external dependencies!
Overview and Python reference implementation:
approx. 60 lines of real code
Java version of hy36encode() and hy36decode()
approx. 190 lines of real code
ANSI C (1989) version of hy36encode() and hy36decode()
Optional: hybrid_36_c.h (as text) (view)
approx. 240 lines of real code
Fortran 77 version of hy36encode() and hy36decode()
approx. 290 lines of real code