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Full Version: Why did they separate Cas and non-cas?
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I googled and searched this forum without finding a satisfying answer. What are the advantages of separating the two modes?
A discussion on that topic was held last December before the board went to the new software: http://www.hpmuseum.org/cgi-sys/cgiwrap/...591#257591
Is that it? It boils down to me either wanting 3.46... or 2*sqrt(3)? Why not just something more like press enter for exact and shift enter for approx? (I don't even have the calculator yet it arrives Monday, but I really need to hit the ground running with it)
Can I turn off the default setting that each variable is initialized as 0 in the home mode? Im scared I forget about that in an exam.
(02-16-2014 03:25 AM)DeucesAx Wrote: [ -> ]Is that it? It boils down to me either wanting 3.46... or 2*sqrt(3)? Why not just something more like press enter for exact and shift enter for approx?

Good news: They must have either read your mind, or you read theirs. You can do exactly what you suggested in CAS. Check it out:

$$\sqrt{12}$$ Enter --> $$2\sqrt{3}$$
$$\sqrt{12}$$ Shift Enter --> 3.46410161514
$$\sqrt{12}$$ Enter [a b/c] --> both answers (best of both worlds!)

HP made it exactly the way you suggested. Cool, huh?

Quote:Can I turn off the default setting that each variable is initialized as 0 in the home mode?

No, because the built-in Home variables are like the 4 stack levels in traditional RPN calculators, always existing and always containing something. Prime's A through Z always exist, and contain zero until you replace the zero with some other real number; Z0 through Z9 always exist and contain zero until you store a complex number in them; and so on.

Quote:Im scared I forget about that in an exam.

No problem: to avoid accidentally using a variable that you didn't initialize, stick to user-created variables, which can nicely have descriptive names, and do not exist until you store something in them, and cease to exist when they are deleted.
Here is a similar apporach if Exact is checked in your CAS settings:

$$\sqrt{12}$$ Enter --> $$2\sqrt{3}$$ --> symbolic result
[a b/c] --> 3.46410161514 --> numeric result
[a b/c] --> 3650401 / 1053780 --> exact result

See the attached screenshot.

Best,
Dominik
Thank you. I guess for now Ill just use the CAS mode at all times.
Could you give some examples where it would be advantageous to use both at the same time?
:O maybe this separation (illogical from an engineer viewpoint) was to offer the ability to block the CAS :O? (I realized this thinking on how TI handled this... 2 different calculators, one without CAS, one with... a much worse decision, imagine if you got the non-cas as a gift, instant boomer; but at last something kinda required by education viewpoint)
One other nuance is that CAS mode doesn't currently support RPN entry: if you want exact results, you're stuck with algebraic entry—and extra keystrokes.

- John
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