Limits with HP50G

[DavidM]

(08-23-2022 07:23 PM)Gil Wrote:  When pressing ENTER, an error appears relative to the = sign.

Yes, that is due to the same error.

(08-23-2022 07:23 PM)Gil Wrote:  It seems impossible to edit your given example and replace, for tan(x), x=pi/2 +0 by x=pi/2-0.

Actually, I think I may have stumbled on a way to do it. It's ugly, but it appears to work.

Let's say you want to type in the limit expression instead of using the Equation Writer app. I'll use the example given above and change the "+0" to a "-0".

Let's start with the same string identified in my previous post:
"'lim(TAN(X),X=\pi/2+0)'"

Edit the string as follows:

1. Place a single backquote character (`) at the very beginning of the string
2. Change the "+0" to a "-0"
   

This leaves us with a rather ugly string on the stack:
"`'lim(TAN(X),X=\pi/2-0)'"

Assuming the flags are set as described, executing STR→ will successfully convert that limit expression to what is intended. This works because the backquote essentially changes the interpreter for what follows in the string to one that knows how to compile a limit expression properly.

(08-23-2022 07:23 PM)Gil Wrote:  By the way, how to have the full list of flags appear on the calculator?
If MODE Flags, the flags status 1..3 appear,
but then there are laps ("holes"), with for instance next flag status shown being 14.

The flag browser section of MODE is hard-wired to show what it does. I don't know of any way to have it show additional flags -- it simply wasn't designed to be configurable.

The best set of descriptions of 50g flags that I know of is in the 50g Advanced Users Reference, Appendix C. Some of the descriptions are still vague and don't give much insight to what the flags actually do, but it's better than no description at all!