Sometime ago I've bored all people in this list with a wish espressed by a
teacher of the high school were I work.
He wanted to restrict the plotting functions only to the real scope of
numbers (I'm not a mathematician and my knowledge of english is poor so
please forgive my mistakes, eventually). To extend the concept Maxima could
be made avare to treat some "base tipes" numbers like integer, natural, rational,
real or complex (and it could be made extensible too). Such a "typized" CAS would
resolve automatically the problem of having to plot the result of an
equation like this:
plot2d([sqrt(x-2) * sqrt(x-4)], [x,-5,5]);
only in the _real_ field.
I suggested the broken hack of tracing the single results for having the
immaginary part different from zero for plotting. Someone, rightly, argued
that this way of working is not well defined since one could always add -i*i
(where i = sqrt(-1)) anywhere in the formula invalidating any part of it.
Well, defining the field of operations from the start could be the answer to
this point since in the real field the "i" number is not defined so you
cannot arbitrarly add it in the formula.
This feature will make Maxima the first professional CAS enabled for the more
wide audience of the high school!
Please be patient, sometimes I do not know what I say! :-)
--
Marco Ciampa
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| Linux User #78271 |
| FSFE fellow #364 |
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