[TIB] A TI-83 research question

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[TIB] A TI-83 research question



Since I managed to stir up so much controversy with my
first TI-basic question, here's a hopefully less-challenging
question.

  How do the following constructs affect the speed of a
Basic program on the TI-83 (yes, the "83-")?


  (1)  While loops as opposed to Repeat loops.
         I've heard that Repeats are faster, I think,
         but is this empirically true?

  (2)  Breaking out parts of a program into
       subprograms.
         In other words, which fragment is faster:

           prgm:ABCDE           or    prgm:ABCDE
           :If getKey:Then            :If getKey:Then
           :*do lots*                 :prgmFGHIJ
           :*of stuff*                :End
           :*here*
           :End                       prgm:FGHIJ
                                      :*do lots of stuff here*
                                      :Return

  (3)  Using Lbls with Gotos.
         I've heard that Goto scans the program for
         Lbls starting at the top and going down.  Is
         this empirically true?  Does it matter where in
         the program file the Goto occurs?
          Are one- or two-character Lbls significantly
         better with respect to speed?

I'm especially interested in point (2), since my philosophy
is to keep the number of program files to a minimum.  Rogue
has two files, one of which contains a subroutine library
that looks something like this:

     prgm:ZROGUE
     If Ans="DESCMONSTER
     Goto DM
     If Ans="DESCOBJECT
     Goto DO
     If Ans="TRYMOVE
     Goto TM
     Lbl DM
     name of monster -> Str1
     Return
     Lbl DO
     ...

Then when I need to print a message, I can call the subroutine:

     prgm:ROGUE
     ...
     "DESCMONSTER
     prgmZROGUE
     Disp "THE "+Str1+" HITS!

It would probably speed up the game to break out the subroutines
into prgmZDMONST, prgmZDOBJ, prgmZTRYMOVE, and so on, but would the
annoyance to the player (at having his calc Prgm menu be filled with
the programmer's subroutines) be worth the speed-up?  That's why I
want to know about empirical tests of point 2 in particular.

Thanks,
 -Arthur
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