+- 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: Equation in solve app not solving (/thread-3748.html)
Equation in solve app not solving - Alfon - 04-30-2015 01:26 AM
Hi,
I put an equation into the Solve app- E1-
L= (P)* (1- (1/(1+R)^N))/R
Then put numerical values into L,P,R and tried to solve for N. I did this by pressing the Num key on the calculator then first pressing Blue-Shift clear to zero out anything in the variables then entering values. Then highlighted the value I wanted to solve for and pressed Solve then nothing happened.
It remained 0 (incorrectly).
Am I missing something here?
RE: Equation in solve app not solving - Tim Wessman - 04-30-2015 03:55 AM
Which variable? What values did you enter?
RE: Equation in solve app not solving - John Colvin - 05-01-2015 07:19 PM
The formula will solve for N with the appropriate guess values for the other variables. By clearing out all of the variables to zero, you will always get a "Bad Guess" error.
For example: L = 100, P = 50, R = 0.25 and solving for N gives N = 3.10628...
RE: Equation in solve app not solving - Alfon - 05-13-2015 11:37 PM
Unfortunately it seems the solver app doesn't work right. I used eg L=100000 P=2000 R= 0.00281, tried to solve for N and nothing happened. Then I used my HP 50 and got the correct result (N=53.95...). I tried several other values as well, but the result doesn't come up correctly on the Prime?
RE: Equation in solve app not solving - Helge Gabert - 05-14-2015 12:00 AM
Works fine for me in the solve app (53.956...). Version 6975.
What are your home settings? Did you try fsolve?
RE: Equation in solve app not solving - Marcio - 05-14-2015 12:02 AM
The same here. In actually, this is one of the few areas where the Prime outperforms the 50g.
RE: Equation in solve app not solving - Alfon - 05-14-2015 12:23 AM
Changed integers setting in Home Settings to Binary (was some other value before) and it works! Thanks.
PS subsequently also checked the digit grouping Setting in Home--looks like the , (comma) used for thousand place holder was giving me this error.