by bobwolfson » Fri Dec 28, 2012 4:06 am
Thanks for replying Garth. Since I'm new here, I'm glad to "meet" you.
As I said in my question, I already know XEQ can accept numeric parameters, and I see what that ability can be used for. But my question was not about that.
My point was that, at least as a newbie, by far the majority of the time, whether in execution or program mode, I want to invoke XEQ with an alpha parameter. Yes, I can see that one might write programs that take advantage of XEQ (numeric label), but long before one gets there, one is going to have to use XEQ (alpha label) and XEQ (function) a ton of times. And every time, one is going to have to remember to press ALPHA right after XEQ, with problematic consequences if one forgets.
For example, the manual introduces the non-keyboard FACT function in an early chapter. Say I want to check it out for myself and I press XEQ F U N C, and while focused on finding the keys with the right letters I fail to look at the display and don't realize I've forgotten to go into ALPHA mode. By the time I look, "9_" is in the display, and, uh-oh, what else have I done. Well, I've swapped X and Y, added a stat observation, and taken the square root of what used to be Y. Ugh, I've messed up my state. Tell me that never happened/happens to you!
The question is, why didn't HP design things in reverse, i.e. so that the calculator defaulted to assuming one would follow XEQ with an alpha parameter, and allow one to get back to numeric parameter entry mode by pressing ALPHA (with the alpha entry empty)? It would save a keystroke every time one actually wanted to provide an alpha parameter to XEQ (which I sincerely believe is the majority case by far). Plus, if one meant to supply a numeric parameter but forgot to press ALPHA to go to numeric entry mode, one would merely be mistyping digits into the alpha scratch register, which isn't going to mess up the calculator's state at all.
E.g., suppose it worked as I'm suggesting and, intending to provide a numeric param to XEQ, one mistakenly pressed XEQ 1 0 instead of XEQ ALPHA 1 0. He looks up at the display, sees "10_", and realizing his error just backspaces twice, presses ALPHA and is now where he wants to be. The cost of a mistake in this scenario is insignificant, where in the prior example one has to seriously think about how to reverse the messed up state (if it's even possible).
Please understand, I'm not trying to "dis" HP or the 41. It's a marvelous machine and it's designers should rightfully have been proud of themselves. Yet, they don't seem to have optimized the entry of an XEQ instruction around the most common usage scenario, leaving the user in greater danger of hurting himself than if they had. Unless they had a reason I'm not grasping, I feel it was a fairly obvious mistake.