Pack and unpack MPC designations

Overview of tools for asteroid observers on this site

If you run into questions/problems, please contact me. You can click here for the source code (look specifically at unpack.cpp and mpc_fmt.cpp; see desigcgi.c for the code underlying this on-line tool to see how the functions are actually used.)

This should handle all the Byzantine ways in which MPC designations can be packed and unpacked. To provide some specific examples :

<- Packed ->    <- Unpacked ->
     J95X00A    1995 XA
     K07Tf8A    2007 TA418
    SK03J020    S/2003 J 2
    SJ45Ux90    S/1945 U 599
0041P           P/41
3141P      e    P/3141-E
3141P     az    P/3141-AZ
    DJ65Az9c    D/1965 A619-C
    XJ65K810    X/1965 K81
     PLS2040    2040 P-L
     T3S3141    3141 T-3
00433           (433)
G4060           (164060)
n1415           (491415)
~0000           (620000)
~000a           (620036)
~AZaz           (3140113)
~zzzz           (15396335)
U024S           Uranus XXIV
N924S           Neptune CMXXIV
N089S           Neptune LXXXIX
U410S           Uranus CDX
     _QC0000    2026 CA620
     _QC0aEM    2026 CZ6190
     _QCzzzz    2026 CL591673
     _AH9fZ7    2010 HJ92809
    P_WY0Mpc    P/2032 YT4130
    C_MPCmpc    C/2022 PY122525

(The above are drawn from a file of test cases used in a test program to verify that my code correctly packs/unpacks designations.)

MPC cheerfully states that the extension allowing packed provisional designations past cycle 620 = 15500th object in a half-month will not be used after the end of 2035, and that therefore the year in such designations (including the last five lines shown above) will be designated by an uppercase letter. I am less sanguine and am allowing lowercase letters (hence base-62) to allow the extension scheme to work to the end of 2061. With any luck, I'll be dead by then and somebody else can worry about it :

     _cRAZaz    2038 RO101424
     _xMDZ3v    2059 MX129941
    X_rAndom    X/2053 AM473865