negative number raised to even power

[rprosperi]

(04-26-2015 09:39 PM)Marcus von Cube Wrote:  

(04-26-2015 08:17 PM)rprosperi Wrote:  Playing further however, I've discovered that:

Starting with 0.00 in display, I type:

[-] [2] [shift] [Y^X] [2] [=] yields 4

whereas [-] [2] [x^2] [=] yields -4

Are you using chain mode? [Y^X] is an operator with two arguments and thus completes the pending operation [-] before being executed. [x^2] just squares what is in the display, 2 actually, and the [-] operation is carried out with the result of this operation.

These subtle cases are useful to see how even consistent rules of precedence can lead to unintuitive and even seemingly inconsistent results. I didn't realize the 2-arg operator needed to complete the pending operation prior to being evaluated. Like many things, once you see it, it makes sense, but as noted earlier, one wouldn't expect different results using these 2 different function methods.

I would not have guessed this original topic/question could lead to such an interesting and revealing discussion. Thanks for the additional comments Marcus.