Clear Stack (CLST, CLSTK) and LastX

[Dieter]

(03-12-2015 09:14 PM)MarkHaysHarris777 Wrote:  First, its not necessary because it is not a 'necessary' use case... I can use the 35s all day and 'never' touch the LASTX key; similar, I can use the 35s all day and 'never' touch the [ENTER] key either... they are not necessary.

Sure - you can always store X in a separate register before any operation is performed. This way the additional effort is limited to one STO command (and 7 to 37 bytes of additional memory usage). But the idea behind LastX is to avoid exactly this STO as it is done automatically on every operation.

(03-12-2015 09:14 PM)MarkHaysHarris777 Wrote:  Second, give me one use case where LASTX is a mandated case where the computation could not be done using another method as easily or more easily?

Since you suggest there is always another method at least as easy (if not easier) than LastX, let me ask the question the other way round: please give an example that can be done easier than with the usage of LastX. ;-)

(03-12-2015 09:14 PM)MarkHaysHarris777 Wrote:  I do not question you. You probably do make use of LASTX frequently... the question is not whether you use it, or like it, the question is whether LASTX is mandated, required, or necessary?

Not even the [–] key is necessary as you can always use [+/–] [+]. The same holds for [√x], for [1/x] or for [tan] (which is [SIN] [LastX] [COS] [/] ;-)). With more or less additional effort many functions can be replaced. You can even press [STO][A] before every single operation to avoid LastX and still have the last operand saved somewhere. But that's not the idea behind a decent calculator. ;-)

Dieter