Reader's digest: The HP Prime heritage on case sensitivity

[jebem]

(09-01-2014 04:49 AM)Angus Wrote:  Hmmm. I would consider the behaviour described in the text being the result of case sensitive input. I don't see a real parallel to the prime. There is no auto-correction of templates mentioned. He can assign everything to any variable (if no reserved word of course). There is no need of changing the typing during usage etc. I agree with the last aspect. That is bad, but the prime gives lower and upper case letters in the display.
What triggered your mind? Or can you say it was the author's confusion some users experience with the prime?

I see what you mean and agree with you on all points.
However I would like to clarify one aspect:
This confusion comes from the machine's project designers, not from the the users. As i see it, the users are the victims here.

Even with very well documented features and behaviors (and we all know that this is not the case in most of the projects due to a number of good reasons, no matter what manufacturer we are talking about here), if something is not consistent or is implemented in a non efficient way from the operation point of view, it is still the manufacturer's fault, not the user's fault.

But I was not looking into specific details, I was just pointing out that this calculator designer's confusion between uppercase/lowercase command and variables in distinct environments (CAS vs Home) in the Prime has got an heritage from the 28 series machines where similar designers confusion were detected by the users at the time (the 28 series were the first world pocket calculators to feature symbolic calculus if I'm not wrong).

The whole concept of distinguish between lowercase and uppercase chars looks fine to me, as long as the machine can maintain the behavior consistency/integrity between the offered distinct environment modes (Home vs CAS).
The Prime has space for improvement here, as discussed by many posters in these forums.

Just a small example of this bad behavior that the users will face after 10 minutes playing with the machine:
- Type an expression in CAS mode using "x" variable (it will be entered as lowercase), for instance a simple definite integral and verify that the correct result is displayed in CAS;
- Now copy the expression into the Home mode and try to get the result: you will get an syntax error instead.
To fix this, the confused user need to manually edit the expression and replace the lowercase variable names with uppercase ones.
Now, I don't see any advantage in this Prime behavior, but maybe others may have a good explanation for this.