How does the DM42 accuracy compare to other calculators ?

[Logan]

(12-21-2017 07:01 PM)Dieter Wrote:  By pressing CPX on the 34s you do not tell the calculator to return a complex result. Instead, you tell it to calculate the function of a complex number in X and Y (instead of a real number in X). Of course the result may be real: Try 1 ENTER 0 CPX x² and get –1 as the correct answer.

So there is no need to know if the result is going to be complex or not. CPX tells the calculator that your input is complex.

That is likely technically correct, but when I tried taking the log of -2 on the 34s, it tells me domain error, or something like that.

While on say, my 42s, it simply returns a complex number (since I have complex results turned on). I suppose the problem with that method for the 34s is that you would have to have some indicator that there is a complex result stored in both the x and y register. Maybe there is a way to do that (some complex results equivalent switch).

So in this case, I tried ln(-2), received an error, and then did ln(-2 +i0), which returns the expected result. That's why I was saying you almost had to know the result was going to be complex. Unless there is some cpxres switch I haven't found (likely).