A case against the x<>y key

[hansklav]

(05-10-2015 02:20 AM)Mark Hardman Wrote:  

(05-09-2015 10:49 PM)hansklav Wrote:  The implied parentheses should be placed as follows:
\(1 - b + c + d = (1 - b) + c + d\)
So you have to do this part of the calculation backwards using …CHS 1 +:
\(1 - b + c + d = 1 + -b + c + d\)
or you should do the \(1 - b\) before adding it to the rest of the calculation: … 1 x<>y – +.

Your point is valid. But, why do you feel that a negative b term (-b) is even necessary?

Simply let the stack do its job:

Code:

1 [Enter]
3 [Enter]
4
Y^X
2
x
5
/
-
etc.

"Inside out, left to right"

Well, as Paul Dale pointed out, on a four level stack RPN calculator then you will run into trouble (stack overflow, leading to a wrong answer, without warning), unless, of course, you make use of STO and RCL.

Hans