Using rsolve with hp prime - Printable Version +- HP Forums (https://www.hpmuseum.org/forum) +-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html) +--- Forum: HP Prime (/forum-5.html) +--- Thread: Using rsolve with hp prime (/thread-5313.html)

Using rsolve with hp prime - wawa - 12-11-2015 06:45 PM Hi I'm trying to get an explicit formula for the sequence u(n)=4*u(n-1)-5*u(n-2)+2*u(n-3) u(1)=1 u(2)=14 u(3)=43 With Xcas, I have no problem with the following line : rsolve(u(n)=4*u(n-1)-5*u(n-2)+2*u(n-3),u(n),[u(1)=1,u(2)=14,u(3)=43]) I get the correct answer. With the prime, I don't know how to do the same It is the [u(1)=1,u(2)=14,u(3)=43] part I don't see. I tried [] and {} delimiters with no success. Do you have any idea how to solve this on the prime ? Thank you. RE: Using rsolve with hp prime - Helge Gabert - 12-11-2015 07:18 PM Works for me. I get [-3*n+2^n*8-12]. Are you sure you are running rsolve in CAS? RE: Using rsolve with hp prime - wawa - 12-12-2015 11:24 AM Thank you for your answer. Yes I am in cas. I tried the rsolve command on the emulator and it does work, but on the calculator, the same command gives me nothing. RE: Using rsolve with hp prime - DrD - 12-12-2015 01:55 PM I get the attached result, with software version 8151, on the hardware calc: (Find your software version: Help | Tree | About HP Prime) [attachment=2941] [attachment=2944] -Dale- RE: Using rsolve with hp prime - wawa - 12-12-2015 02:58 PM I don't get it. I have the 8151 firmware. Here is another screenshot with the end of the line. Maybe I mistyped something or maybe there is something special with my settings but I compared with the emulator on which the rsolve command is doing OK and I don't see any difference. RE: Using rsolve with hp prime - Helge Gabert - 12-12-2015 03:31 PM Hmm . . . maybe something to do with the CAS settings? However, I can only see that unchecking "exact" throws an error message, but not empty brackets. What are your settings, especially the recursive values on p. 2? RE: Using rsolve with hp prime - wawa - 12-12-2015 03:55 PM my CAS settings are : and I tried the DrD's setting for page 2, with no more success : still empty brackets. RE: Using rsolve with hp prime - wawa - 12-12-2015 04:15 PM I think I figured out the problem : I have a CAS variable named n with a value of 0. Now my problem is to purge this variable. I tried purge(n) and purge() but with no success Edit : It works ! I had a Hanoi program with an "EXPORT ...,n,..." command inside. I deleted this program and my variable n disapeared. The rsolve command is now running properly RE: Using rsolve with hp prime - Helge Gabert - 12-12-2015 04:21 PM Did you try restart? RE: Using rsolve with hp prime - wawa - 12-12-2015 04:52 PM yes I tried the restart command with no success because my variable n was exported in a program. I had to delete this program to get things work. RE: Using rsolve with hp prime - Helge Gabert - 12-12-2015 09:25 PM Good to know - - I'm glad you figured it out!