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newRPL: [UPDATED April 27-2017] Firmware for testing available for download
10-05-2015, 02:05 PM (This post was last modified: 10-05-2015 03:21 PM by Han.)
Post: #50
RE: newRPL: [UPDATED Oct-01-2015] Firmware for testing available for download
(10-05-2015 12:11 PM)Claudio L. Wrote:  
(10-04-2015 09:57 PM)Helix Wrote:  I don't know yet if this is a good idea. Existing programs for the HP50g with trigonometric functions inside will have to be entirely edited to be used with newRPL. Also, I'm afraid that function names like SIN COS TAN are so natural that it will be very easy to make errors in writing or editing programs…
The idea is that if you are writing or editing a program let's say in DEG mode, the SIN key will not only compute SIND, but also type SIND in your program and SIND() in your algebraic expressions, this makes it clear it's in degrees.
But yes, it breaks compatibility with any existing code using a mode other than radians. On the other hand, CAS programs are always forcing the radians mode on you, so those will not be affected. Non-CAS programs will be using SIN, so not affected either.
One advantage is that in CAS programs, by having a different name, the derivative of SIND for example, could automatically be PI/180*COSD(u)*u', no mode change needed.
I don't know, I'm still debating myself if this is really "better", hence is still not implemented. Perhaps more comments from people can help clear this out.

(10-04-2015 09:57 PM)Helix Wrote:  However, if you implement this feature, I think I would prefer command names like SIND, SING, instead of DSIN, GSIN…
Now that you mention, I prefer SIND too (so I started using it above already).

Sometimes less is more. I find that after some point, having too many commands becomes cumbersome. We have units, including ° should we want degrees. The trig functions should always assume radians (in my opinion) or at the very most depend on the angle mode. Users who wish to explicitly use an angle measure that is invariant under angle mode should specify the units. A custom key can be set up to quickly add the appropriate units. In programs, the explicit unit only needs to be appended once as subsequent operations would inherit the initial unit.

EDIT: My proposal also does away with the derivative issue; e.g. the derivative of SIN(X) will always be COS(X) since the trig functions should presumably know how to auto-adjust for inputs that are properly tagged with units of angle measure (and assume radians otherwise).

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RE: newRPL: [UPDATED Oct-01-2015] Firmware for testing available for download - Han - 10-05-2015 02:05 PM



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