[A83] Re: TI83 CAS


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[A83] Re: TI83 CAS




Root/Great Overall Dictator replies:
> Here's just a few ideas I've come up with about it.
> 
> TI83 Computer Algebra System
> Requirements:
> Expansion of equations, for example, binomial expansion
> Solving of equations for a single variable (two isn't practical for a TI83)
> Factorising of equations (like Factor7, but without the need to enter terms
> separately)
> Exact answers (eg, display 1.41421356 as the square root of two)
> Deriving/Antideriving of equation (eg, antideriving 2x gives x^2+c), not
> just a numerical answer between 2 points
> Link all the CAS functions into a new menu, possibly accessable by using a
> combination of buttons like MirageOS does to load up
> 

I know some of this can be done in basic (i have done some of it), but only
as a really specific case. (eg 1st and second derivative of polynomials)

> Problems:
> Only 27k of memory to work with, and practically can only use a percentage
> of that

That could be fixed (on 83+): Create it as an app (one or more 16K pages) and
have it archive all programs when it starts, leaving all ~27K free. 

> Speed problems; string manipulation takes ages on a TI83

Going to be a problem for any z80 even the 83+SE

> Actually working out how to manipulate the equations

Have fun :)

> Using letters as constants in equations rather than numbers
> 

The way tios works, it isn't (practically) possible. 

> If anyone has any ideas on any parts of this, please reply!

Essentially, you are going to have to dump the whole TIOS's way of doing
things. Basically writing a whole OS in RAM (83) or Flash (83+)

I know several people have started on one, but haven't gotten very far. My
guess is that trying to get a c compiler to work well (port gcc, get zcc
working well), you could use one of the gpled CASes (after extensive
modification)

James L

 > Tim Crockford




References: