Threaded Mode | Linear Mode

Ummon · 03-06-2018, 09:09 AM

I'm using the latest version : 2018.02.12 1.4.1.13441

Put the calculator in degree mode
In numeric mode evaluate an integral from 0 to 10 of sin(X^2)dX
The calculator reboot nearly instantaneous

It also crashes with the virtual calculator on Windows.

Marcel · 03-07-2018, 02:04 PM

Hi!

Same for me... my calculator reboot.

Marcel

Arno K · 03-07-2018, 03:11 PM

Funny enough that you tried to integrate a trigonometric function in degrees.
Arno

Marcel · 03-07-2018, 05:34 PM

Hi,
Here, the angular mode is not the problem..
The prime don't have to reboot on this simple calculation.
Marcel

John Colvin · 03-07-2018, 07:23 PM

Mine crashes also. Interestingly, the same integral dosen't crash my 49G+ in degree
mode, but it does give an incorrect answer - 4.66682...
But the fact remains that the Prime should not crash simply because the degree
mode is used instead of radian mode. Definitely a bug.

Carsen · (This post was last modified: 03-08-2018 04:57 AM by Carsen.)

John Colvin. My HP 50g got the right answer of 4.66829167156. I believe the 49G+ should get the right answer as well. Did you accidentally put in the lower and upper bound in the wrong order?

Joe Horn · 03-08-2018, 05:04 AM

(03-08-2018 04:48 AM)Carsen Wrote: My HP 50g got the right answer of 4.66829167156.

Your answer is what the 50g gets in FIX 4 mode, leaving a pretty big value stored in IERR. STD mode takes a few seconds longer but returns 4.66829104623 with a much smaller IERR.

parisse · 03-08-2018, 06:37 AM

This bug is already fixed in source code. Until it is available in a new firmware, you can run int(sin(x^2),x,0,10.0)

Carsen · 03-08-2018, 06:45 AM

(03-08-2018 05:04 AM)Joe Horn Wrote:
(03-08-2018 04:48 AM)Carsen Wrote: My HP 50g got the right answer of 4.66829167156.

Your answer is what the 50g gets in FIX 4 mode, leaving a pretty big value stored in IERR. STD mode takes a few seconds longer but returns 4.66829104623 with a much smaller IERR.

Huh. That's neat. I did not know about Integration Error (IERR) variable. I also didn't know (or forgot) that the number format changes the precision of the answer. Like the 15C. Learn something new everyday. Thanks Joe Horn.

DA74254 · 03-08-2018, 02:41 PM

I tried in on my SM42. It went into an indefinite loop. Even with accuracy of 0.1

jebem · (This post was last modified: 03-08-2018 03:06 PM by jebem.)

(03-08-2018 02:41 PM)DA74254 Wrote: I tried in on my SM42. It went into an indefinite loop. Even with accuracy of 0.1

"SM42" or "DM42"?

Anyway, it is always better to experience a machine reset than an infinite loop, so in this regard the HP Prime wins hands down Smile

DA74254 · 03-08-2018, 03:20 PM

(03-08-2018 03:04 PM)jebem Wrote:
(03-08-2018 02:41 PM)DA74254 Wrote: I tried in on my SM42. It went into an indefinite loop. Even with accuracy of 0.1

"SM42" or "DM42"?

Anyway, it is always better to experience a machine reset than an infinite loop, so in this regard the HP Prime wins hands down

SM DM42

Anyway, I was a bit quick as I set up sin (x^3) which went on and on. With the correct integration it spent abt 4 sec. to get 0.5836... in RAD and almost instantly 4.6682... in DEG mode. (And 4.3825... in GRAD mode)

John Colvin · 03-08-2018, 08:25 PM

(03-08-2018 04:48 AM)Carsen Wrote: John Colvin. My HP 50g got the right answer of 4.66829167156. I believe the 49G+ should get the right answer as well. Did you accidentally put in the lower and upper bound in the wrong order?

Am I missing something here? How is 4.6668.... the correct answer? If I convert
10 deg. to pi/18 red. in the upper boundary, I get a result of 0.001772.... on my
50G as well. A graph of sin(x^2) clearly indicates that in this interval, the area
under the curve is quite small.

Joe Horn · (This post was last modified: 03-08-2018 08:54 PM by Joe Horn.)

(03-08-2018 08:25 PM)John Colvin Wrote:
(03-08-2018 04:48 AM)Carsen Wrote: John Colvin. My HP 50g got the right answer of 4.66829167156. I believe the 49G+ should get the right answer as well. Did you accidentally put in the lower and upper bound in the wrong order?

Am I missing something here? How is 4.6668.... the correct answer? If I convert
10 deg. to pi/18 red. in the upper boundary, I get a result of 0.001772.... on my
50G as well. A graph of sin(x^2) clearly indicates that in this interval, the area
under the curve is quite small.

Yes, 10_deg = pi/18_rad, but sin((10_deg)^2) is not the same as sin((pi/18_rad)^2). Plot the sin(x^2) from 0_deg to 10_deg and you'll see it. The integral from 9 to 10 alone is almost 1.

[Image: int10.png]

John Colvin · 03-08-2018, 09:09 PM

(03-08-2018 08:47 PM)Joe Horn Wrote:
(03-08-2018 08:25 PM)John Colvin Wrote: Am I missing something here? How is 4.6668.... the correct answer? If I convert
10 deg. to pi/18 red. in the upper boundary, I get a result of 0.001772.... on my
50G as well. A graph of sin(x^2) clearly indicates that in this interval, the area
under the curve is quite small.

Yes, 10_deg = pi/18_rad, but sin((10_deg)^2) is not the same as sin((pi/18_rad)^2). Plot the sin(x^2) from 0_deg to 10_deg and you'll see it. The integral from 9 to 10 alone is almost 1.

That''s what I missed, Joe. Thanks.