Search found 571 matches

by Walter
Sat Feb 16, 2019 10:16 am
Forum: Discuss!
Topic: Little Problem with Complex Mathematics on Calculators
Replies: 7
Views: 221

Re: Little Problem with Complex Mathematics on Calculators

Thanks to Bob, Didier, and Haakon for responding so far. My basic question was: why is i ∞ = 0 + i ∞ but it looks that (i ∞)^2 ≠ (0 + i ∞)^2 ? Reasoning for the second equation: (i ∞)^2 = -∞ while (0 + i ∞)^2 = 0 - ∞ + 2 i 0 ∞ (this expansion of the squared parenthesis doesn't assume anything IMO). ...
by Walter
Fri Feb 15, 2019 9:25 pm
Forum: Hardware issues
Topic: Improved Keyboard????
Replies: 14
Views: 406

Re: Improved Keyboard????

The problem has been identified. It seems the metal sheets from which the metal domes were stamped weren't cleaned properly. An oil film prevents reliable contact. The domes and the contact area on the PCB can be cleaned, which significantly improves the reliability. I am really sorry, but every de...
by Walter
Thu Feb 14, 2019 8:57 pm
Forum: Discuss!
Topic: Little Problem with Complex Mathematics on Calculators
Replies: 7
Views: 221

Little Problem with Complex Mathematics on Calculators

I came across the following quite simple calculation: 0 [1/x] [+/-] returns -∞ . We all know that SQRT( -∞ ) = i ∞ . The calculator returns 0. + i ∞ which is perfectly equivalent. Now let's revert this last operation by squaring: (i ∞ )^2 = -∞ . So far so good. But (0 + i ∞ )^2 = 0 + ( -∞ ) + 2 i 0 ...
by Walter
Thu Feb 14, 2019 12:16 pm
Forum: Hardware issues
Topic: Improved Keyboard????
Replies: 14
Views: 406

Re: Improved Keyboard????

The problem has been identified. It seems ... Hear, hear! ... the metal sheets from which the metal domes were stamped weren't cleaned properly. An oil film prevents reliable contact. The domes and the contact area on the PCB can be cleaned, which significantly improves the reliability. We encourag...
by Walter
Wed Feb 13, 2019 9:56 am
Forum: DM42
Topic: Looking forward to the DM42 update utilizing the Free42 2.023 update...
Replies: 16
Views: 469

Re: Looking forward to the DM42 update utilizing the Free42 2.023 update...

The point being discussed here is not IF the 2.023 changes should be included in the DM42, of course they should! The point being discussed is WHEN to include the changes and make a new release. ... ... I just don't understand all this frenzy about updates: it's not that the calc doesn't work, nor ...
by Walter
Sun Feb 10, 2019 10:57 pm
Forum: DM42
Topic: Benchmark test e^x^3
Replies: 5
Views: 225

Re: Benchmark test e^x^3

Beginner wrote:
Sun Feb 10, 2019 9:12 pm
The TI NSpire can calculate the intervall of e^x^3 between 0 and 13 (result: 2,75 E951) quite fast. It's limit is E999.
How fast is "quite fast"? Just for curiousity ...
by Walter
Sun Feb 10, 2019 10:51 pm
Forum: DM42
Topic: Finally deciding to purchase DM 42. I have a question first however.
Replies: 13
Views: 977

Re: Finally deciding to purchase DM 42. I have a question first however.

grsbanks wrote:
Sun Feb 10, 2019 9:14 pm
You're probably better off ordering direct from SwissMicros anyway: https://www.swissmicros.com/order.php
... and you won't be feeding Amazon.
by Walter
Wed Feb 06, 2019 10:07 pm
Forum: Hardware issues
Topic: Keyboard debouncing
Replies: 63
Views: 6533

Re: Keyboard debouncing

IIRC, far less people complained about ENTER at times when one-line displays were standard. More than two output lines seem to add confusion instead of enlightenment. Just an observation. ;) I've noticed this too Walter, quite weird and unexpected; it would seem that being able to view more of the ...
by Walter
Wed Feb 06, 2019 3:07 pm
Forum: Hardware issues
Topic: Keyboard debouncing
Replies: 63
Views: 6533

Re: Keyboard debouncing

The usual reason folks pursue this is if they learned RPL before RPN, where all terminated entries always enable stack lift. These tricks better simulate the behavior of RPL. Correct, and that's the main reason why we should avoid this and show them the light. :lol: One more reason why WP calculato...
by Walter
Tue Feb 05, 2019 3:21 am
Forum: DM42
Topic: Feature requests
Replies: 15
Views: 1269

Re: Feature requests

Since the release of the DM42, I read continuously complaints about the keyboard :( I don't plan to buy this calculator because of these recurrent and unsolved keyboard problems. Unhappy customers will more probably post their experience here than happy ones. To get an idea of the real order of mag...