HP Prime Bug



#21

1. Go in CAS-Settings and deactivate "Exact"

2. Then In CAS-View type "solve(x³+x²=x,x)"

3. Look what happen.

Whats the matter ? (I have firmware 2013 8 13)


#22

What do you get?

I get the 3 approx results wich seems OK

-1.6...., 0, 0.618...


#23

Look at my video on 0:38. The calculator crash.

http://www.youtube.com/watch?v=YE1LiY6wOZo&feature=youtu.be

Sorry for the bad quality.


#24

Is there anybody who can explain?


#25

I cannot. I have never seen that before. Have you made any changes in the CAS settings screen? If so, please post them.

TW

Edited: 13 Oct 2013, 10:23 a.m.


#26

Hi Tim,

please look also to the video of Edwin. He had the same problem.

I make no other changes in the CAS or general settings. I unpacked the calculator, go in CAS mode, change the exact-mode setting an try to solve the equation.

Tim, can you reproduce the bug of a real HP Prime with firmware 213 8 13 (5106)?

By the way: I have another HP Prime with firmware 2013 7 22. This calculator doesn't reboot but show only the answer {0.} in non-exact mode.


#27

Quote:
By the way: I have another HP Prime with firmware 2013 7 22. This calculator doesn't reboot but show only the answer {0.} in non-exact mode.


press enter again and get a second solution :)

eq0:= x^3+x=x; [ENTER]

solve(eq0, x); [ENTER] => returns a different answer every time you press enter


#28

Quote:
press enter again and get a second solution :)

eq0:= x^3+x=x; [ENTER]

solve(eq0, x); [ENTER] => returns a different answer every time you press enter


The answers are somewhat close to 0. The solutions are on the order of 1E-9 or 1E-18. This behavior is at least consistent with the fact that the CAS is in non-exact mode, but certainly the solver could be more accurate.

That said, there is a setting in the CAS for epsilon. So users will likely expect that the solver be at least within epsilon. The default is 1E-12, so values on the order of 1E-9 are not sufficient.

#29

yes, it is a bug.
I made another video:
http://youtu.be/I1CtxqS5W4g


#30

+1 here. Reboot.


#31

Do you know the reason of the mistake?


#32

No, I've just reproduced the steps and the calculator did a reboot.


#33

really phat!

#34

What is your firmware version?

#35

/!\ TESTED on HP-PRIME VIRTUAL CALCULATOR (Is Not an Emulator)

[CAS MODE & EXACT MODE ON & HP-PRIME "EMULATOR"]

solve( x^3+x=x,x); [ENTER] =>

{((-(v¬(5))-1)/2),0,((v¬(5)-1)/2)} // OK

[CAS & EXACT MODE OFF] (APPROXIMATE)

solve( x^3+x²=x,x); [ENTER] => { -1.61803398875, 0, 0.61803398875} // OK

decoding the previous output

x=-1.61803398875 OR x=0 OR x= 0.61803398875

x^3+x²=x|x=-1.61803398875; [ENTER] =>

-1.61803398875 = -1.61803398875

EVAL(Ans); [ENTER] => 1 (TRUE)

x^3+x²=x|x=0; [ENTER] =>

0 = 0

EVAL(Ans); [ENTER] => 1 (TRUE)

but
eq0:= x^3+x=x;

solve(eq0, x); [ENTER] => returns a different answer every time you press enter

[enter] => ...

Another BUG with equations

solve( x²-10*x+y² = -8 AND x*y²+x-10*y = -8 , { x ,y } ); [ENTER]

=> { [ 1, 1 ], [ 2.19343941541,3.02046646812 ] }

decoding the previous output

x = 1 and y = 1 or x = 2.19343941541 and y = 3.02046646812

[CAS MODE & EXACT MODE ON]

purge(x,y);
x²-10*x+y² = -8 AND x*y²+x-10*y = -8; => 0 ????? BUG

x²-10*x+y² = -8 AND x*y²+x-10*y = -8 | x = 1,y = 1; ==> 1 (true)

Left part (step to step):

x²-10*x+y² = -8|x= 1; => y²-9 = -8

y²-9 = -8|y = 1; =>

-8 = -8 => true

Right part:

x*y²+x-10*y = -8 |x= 1; => y²-10*y+1 = -8

y²-10*y+1 = -8|y = 1; =>

-8 = -8 => true

true and true => true

but

x²-10*x+y² = -8 AND x*y²+x-10*y = -8 | x = 1; => 0 ???? BUG

=> OK => y²-9 = -8 AND y²-10*y+1 => y²-9 = -8 AND y²-10*y+1

Ans| y=1 => true

[CAS & EXACT MODE OFF] (APPROXIMATE)

purge(x,y);
x²-10*x+y² = -8 AND x*y²+x-10*y = -8; => x²-10*x+y² = -8 AND x*y²+x-10*y = -8; // OK


x²-10*x+y² = -8 AND x*y²+x-10*y = -8 | x = 1,y = 1 ==> 1 (true)

x:=1;
y:=1;

x²-10*x+y² = -8 AND x*y²+x-10*y = -8 => 1 (true)


Edited: 13 Oct 2013, 5:10 p.m.

#36

Who is responsible for bugs? Is there an email-address for bugs? Or leaves hp ourselves?


#37

Who is responsible for bugs?

HP-PRIME TEAM

Is there an email-address for bugs? Or leaves hp ourselves?

required bug reporting page

#38

Quote:
Who is responsible for bugs? Is there an email-address for bugs? Or leaves hp ourselves?

I am fairly positive that the folks at HP read the forums here, as well as other forums. I know that Tim, Cyrille, and Bernard in particular are active with the community, as well as many of the beta testers. You may be surprised that they frequent this board, adictoshp, cemetech, omnimaga, tiplanet, comp.sys.hp48 and many other forums.


#39

One reasonable forum would be sufficient.


#40

Quote:
One reasonable forum would be sufficient.

My point was that users can choose to stick to any one forum they prefer. The folks working on the calculator do check all of them so that regardless of where you post, they will be read.

Edited: 14 Oct 2013, 10:48 p.m.


Possibly Related Threads...
Thread Author Replies Views Last Post
  Sending little images to the Prime (...and Program name bug?) Erwin Ried 19 661 12-10-2013, 05:35 PM
Last Post: Erwin Ried
  [HP Prime] Plots containing complex numbers bug? Chris Pem10 7 383 12-05-2013, 07:40 AM
Last Post: cyrille de Brébisson
  [HP Prime] plotfunc() bug in CAS Chris Pem10 2 223 12-04-2013, 02:46 PM
Last Post: Chris Pem10
  HP Prime Spreadsheet Copy bug Michael de Estrada 1 216 12-03-2013, 11:34 PM
Last Post: Walter B
  HP Prime Matrix TERRIBLE bug and question uklo 19 822 11-25-2013, 12:10 PM
Last Post: Mic
  HP Prime graphing bug BruceH 1 175 11-19-2013, 08:14 AM
Last Post: Joe Horn
  [Prime] Shutdown timer bug? Cristian Arezzini 2 178 11-16-2013, 10:34 AM
Last Post: Cristian Arezzini
  HP Prime: Linear Solver app bug BruceH 0 130 11-15-2013, 06:36 PM
Last Post: BruceH
  Possible bug with sqrt function in the HP prime Michael de Estrada 6 317 11-15-2013, 12:49 PM
Last Post: Michael de Estrada
  [HP Prime] Calculating Prandtl Number with Units (bug found in USIMPLIFY) Timothy Roche 1 166 11-13-2013, 04:07 PM
Last Post: cyrille de Brébisson

Forum Jump: