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1. In CAS mode, start with a blank command line. Enter the Units menu and press Const if necessary. Then press - for example 2 (Chemistry) and then 2 (k: 1.3806488e-23). This number is then copied into the command line, but pressing Enter leads to some sort of error. It isn't possible to do any calculation with the number. The error seems to occur with any constant with a negative exponent.

2. In CAS mode, enter (for example) 1_(yd)+2_(in) either directly from the keyboard or using the Units->Units->Length menu to create the unit objects. The calculator gives an error.

3. In CAS mode, MKSA(unit-expression) gives an "Error: Unmatch control word" error message, if MKSA is entered from the Units->Tools menu. However, entering "mksa" (lower case) from the keyboard does not give an error.

These problems only arise in CAS mode (and there may be more - I haven't looked at everything fully yet). Am I doing something silly (entirely possible - it's late here!) or do units no longer work in CAS mode?

Nigel (UK)

_in should be _inch, the reason is that in is a CAS reserved word.

(05-28-2014 06:27 AM)parisse Wrote: [ -> ]_in should be _inch, the reason is that in is a CAS reserved word.

Thank you! That explains one issue - although it would be nice if the Length menu in CAS mode entered "inch" rather than "in". Before anyone starts to question why I was using "yards" and "inches" in the first place, I'd like to point out that it was late, I was tired, and I'd been reading English detective stories from the early twentieth century all day. It won't happen again!

Nigel (UK)

(05-27-2014 10:15 PM)Nigel (UK) Wrote: [ -> ]This number is then copied into the command line, but pressing Enter leads to some sort of error. It isn't possible to do any calculation with the number. The error seems to occur with any constant with a negative exponent.

When the number is copied into the command line, edit it and replace the "E" with a "e".
Then press "enter".

(05-28-2014 11:30 AM)phgerin Wrote: [ -> ]

(05-27-2014 10:15 PM)Nigel (UK) Wrote: [ -> ]This number is then copied into the command line, but pressing Enter leads to some sort of error. It isn't possible to do any calculation with the number. The error seems to occur with any constant with a negative exponent.

When the number is copied into the command line, edit it and replace the "E" with a "e".
Then press "enter".

Thanks - this works. It's strange that this problem doesn't arise when the exponent is positive (e.g., for N_A = 6.02E23).

So it seems all three of the "bugs" mentioned in my opening post can be worked around by entering things differently in CAS mode - changing "E" to "e", replacing the unit "in" with "inch", and entering "MKSA" as "mksa". I would prefer the Prime's menus to enter the correct CAS mode form automatically rather than leaving the correction to me.

It's great having the power of XCAS/Giac on the calculator, but CAS mode is still not living happily side-by-side with some of the non-CAS functions.

However, I'm delighted with the new display modes. "Floating" is great and having separators makes the display so much easier to read. I also note that mksa(_h_) no longer gives zero - thanks, Tim and Parisse!

Nigel (UK)