newRPL: Angles revisited

[Nigel (UK)]

(04-01-2016 01:12 AM)Claudio L. Wrote:  It seems we think alike. Your tags are pretty much the same thing I'm proposing.
The only difference is my proposal of keeping the format of the first argument.
My logic is a bit different, I think of operations as something applied to the number that's on the stack. For example, you have a hex number and you want to increase it. For easy typing, you just want to type 1 +, but you still want the result to be a hex number, hence keeping the first argument format is useful. Same concept helps with temperatures, etc.

For angles, I think the same applies: if you have an angle, it's reasonable to assume if you add a number to it you are adding another angle and want the result to be an angle, you just don't type it as an angle to save keystrokes.
However, when you have a real number and you add an angle, I'm not sure you are working with numbers or angles, so the type should remain "unknown"= real number. At least that's my logic, or it was until I read your post.
I think your logic makes sense too, but I have to think a little more before I break the consistency with all the other parts of newRPL.

Out of interest, what should the calculations 90D 1 + and 1 90D + give in radian mode? On my calculator, 90D 1 + gives 147D and 1 90D + gives 2.57R. In each case, the "1" is treated as 1 radian and the tag for the answer is taken from the first argument. I agree that other approaches can make sense; however, I think it is very desirable that addition should remain commutative. In degrees mode your suggested logic respects this - 91D and 91 are the same quantity, so far as trig functions are concerned. So long as the same is true in radian mode, I'll be content.

Nigel (UK)