The Museum of HP Calculators

HP Forum Archive 21

 HP Prime - Cross product suggestionMessage #1 Posted by bluesun08 on 7 Nov 2013, 3:30 p.m. It will be amazing and user friendly if after pressing the Cross product key automatically come two imput-fields for vectors: cross([],[]) So i can immediately imput the vectors for example cross([1 2 3],[4 5 6]) or cross([a],[b]) if the vectors stored in variable a and b. It also will be helpful in other vector-operations.

 Re: HP Prime - Cross product suggestionMessage #2 Posted by Han on 7 Nov 2013, 4:29 p.m.,in response to message #1 by bluesun08 Quote: It will be amazing and user friendly if after pressing the Cross product key automatically come two imput-fields for vectors: cross([],[]) So i can immediately imput the vectors for example cross([1 2 3],[4 5 6]) or cross([a],[b]) if the vectors stored in variable a and b. It also will be helpful in other vector-operations. What if I already have two vectors stored as a and b? Then this would make me have to delete the []'s since I would want to have cross(a,b). One person's convenience may be another's hassle. Edited: 7 Nov 2013, 4:39 p.m.

 Re: HP Prime - Cross product suggestionMessage #3 Posted by bluesun08 on 7 Nov 2013, 4:51 p.m.,in response to message #2 by Han Think different: It would be amazing if the calculator recognize if there a numbers or a variable. For example you have stored [1 2 3] in a and [4 5 6] in b then cross([a],[b]) expand it internally to cross([1 2 3],[4 5 6]) and calculate the result. In another case if i imput cross([7 8 9],[8 7 6]) the calculator recognize the numbers an calculate the result. As I said, it would be amazing.

 Re: HP Prime - Cross product suggestionMessage #4 Posted by Gerson W. Barbosa on 7 Nov 2013, 5:44 p.m.,in response to message #3 by bluesun08 Quote: As I said, it would be amazing I think you're ahead of your time :-)

 Re: HP Prime - Cross product suggestionMessage #5 Posted by bluesun08 on 7 Nov 2013, 6:22 p.m.,in response to message #4 by Gerson W. Barbosa I write my postings on an apple. And as you can see in the video, apple was always ahead of time.

 Re: HP Prime - Cross product suggestionMessage #6 Posted by Gerson W. Barbosa on 7 Nov 2013, 6:31 p.m.,in response to message #5 by bluesun08 My first computer was an Apple. Well, sort of: I'd like to switch to Apple, but unfortunately Apple hasn't bothered providing a Brazilian keyboard so far... Edited: 7 Nov 2013, 6:34 p.m.

 Re: HP Prime - Cross product suggestionMessage #7 Posted by Jamil on 8 Nov 2013, 5:57 p.m.,in response to message #6 by Gerson W. Barbosa Mine was this complete with manual... Still with me. A very basic "basic"...

 Re: HP Prime - Cross product suggestionMessage #8 Posted by Gerson W. Barbosa on 9 Nov 2013, 7:51 a.m.,in response to message #7 by Jamil Olá, Jamil! Do you remember this ad from 1983? The 16KB version cost about R\$ 1700, or US\$ 750 (today's dollars and reais). Edited: 9 Nov 2013, 7:54 a.m.

 Re: HP Prime - Cross product suggestionMessage #9 Posted by Jamil on 9 Nov 2013, 5:16 p.m.,in response to message #8 by Gerson W. Barbosa Oi Gérson, I can´t remember this entire add but in the 80's I used to listen one radio program (in 93,7 MHz - USP-FM) and they played full "programs" that could be recorded (in cassete tapes)and loaded in TK series computers. I think it was in 1988, I downloaded that background image with "Humphrey Bogart" ( is he?) and impressionate all my family and friends... Great old times... Thanks for makes me remember this. Jamil

 Re: HP Prime - Cross product suggestionMessage #10 Posted by BruceH on 7 Nov 2013, 7:39 p.m.,in response to message #3 by bluesun08 Quote: Think different: It would be amazing if the calculator recognize if there a numbers or a variable. For example you have stored [1 2 3] in a and [4 5 6] in b then cross([a],[b]) expand it internally to cross([1 2 3],[4 5 6]) and calculate the result. In another case if i imput cross([7 8 9],[8 7 6]) the calculator recognize the numbers an calculate the result. As I said, it would be amazing. Yes. What if there were a way you could just pile some values up somewhere - numbers, or matrices, or variables containing matrices - whatever, and then run the cross command and have it just take off the pile exactly the right number of arguments that it needs and interpret them properly according to their type? That would be cool.

 Re: HP Prime - Cross product suggestionMessage #11 Posted by cyrille de Brébisson on 8 Nov 2013, 1:38 a.m.,in response to message #3 by bluesun08 Hello, It would be amazing if as I just brought my fingers close to the calculator keyboard it would recognize that I am trying to type DOT([1,2,3],[4,5,6]), input it for me and gave me the result! Cyrille

 Re: HP Prime - Cross product suggestionMessage #12 Posted by Han on 8 Nov 2013, 1:43 a.m.,in response to message #11 by cyrille de Brébisson Quote: Hello, It would be amazing if as I just brought my fingers close to the calculator keyboard it would recognize that I am trying to type DOT([1,2,3],[4,5,6]), input it for me and gave me the result! Cyrille That's a lot of work -- moving fingers. I should just know what I am thinking and display the answer! Jokes aside, the calculator can only handle so much ambiguity and hence we have to resort to some basic, common means of input that would be appropriate for the largest audience size.

 Re: HP Prime - Cross product suggestionMessage #13 Posted by Wes Loewer on 9 Nov 2013, 12:31 a.m.,in response to message #12 by Han Quote: That's a lot of work -- moving fingers. I should just know what I am thinking and display the answer! Jokes aside, the calculator can only handle so much ambiguity and hence we have to resort to some basic, common means of input that would be appropriate for the largest audience size. You know it's just a matter of time till computers are embedded in the body. I can see it now... "Grandpa, is it true you used to have to push buttons with your fingers and read with your eyes? Wasn't that slower than our direct interface?" or "Come on Mom, I really need the 4-d graphing implant for math class. All the other kids have it but I only have the 3-d graphing implant." It's only a matter of time... -wes :-)

 Re: HP Prime - Cross product suggestionMessage #14 Posted by Patrice on 8 Nov 2013, 1:49 a.m.,in response to message #11 by cyrille de Brébisson Que la force soit avec toi :) May the force be with you Edited: 8 Nov 2013, 1:51 a.m.

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