Geometry: angle measure bug?

[jeffwahl]

Am I doing this incorrectly?

1. Home Setup indicates that angle measure is in degrees (System setting?)
2. Starting Geometry app with cleared variables.
3. Symbolic setup indicates Angle Measure is using System setting, and small green indicator in upper right confirms this.
4. Created a triangle in Plot view, then through Cmds soft key, asked for Measure->Angle and input the three points of the triangle.
5. "angle(GA,GC,GB)" in top right gives result in radians
6. Changing (but not just viewing) angle measure setting in Home Setup or Symbolic Setup to degrees results in Plot view reporting the result in degrees as desired.

Why is the command not using the system setting in the first place? This happens as described above on both my calculator [fw 2.1.14433 (2020 01 21), Hardware Ver. D] and the HP Prime Virtual Calculator in Windows 10 [fw 2018 02 12 (13441), Hardware "Emu"]

[roadrunner]

I think that issue has been known to to Prime team for a while. The fastest way you can correct the display is to press Apps and then Start. But every time you add a new angle measurement they all go back to radians, necessitating the correction again.

-road

[jeffwahl]

Thanks, roadrunner, for the speedy reply, and indeed, your fix works. After posting my question, I saw this behavior was noted and described by Denis Bisson in a comment posted in 2015 on Eddie Shore's blog, "HP Prime Geometry App Tutorial Part 2: Triangles. So apparently it's a feature grandfathered into the operating system.
When this happens, it seems that the angle measure setting is different between Home (degrees) and CAS (radians), yet setting it in either Setup screen will set the other accordingly. I gather that Geometry is a CAS-type app, so perhaps it defers to the CAS setting, whatever it happens to be at the time.

[Joe Horn]

In addition to the global "Home Angle Measure" setting (stored in the HAngle system variable), each app has its own "App Symbolic Setup Angle Measure" setting (stored in the AAngle system variable).

Press Shift Symb to change the current App angle setting. If it's set to "System", then you can press Shift Home to change the current global angle setting. But if the App angle setting is not "System", then you won't be able to change the angle setting in Shift Home (but you WILL be able to change the app angle setting by tapping the angle symbol below the clock display).

The CAS angle setting is the same as the Home angle setting, as you noticed. No, the Geometry app does not prefer the CAS angle setting.

Does the above shed any light on the issue at hand?

[roadrunner]

(04-05-2021 12:36 AM)Joe Horn Wrote:  Does the above shed any light on the issue at hand?

I don't think that's the issue. Try these steps:

1. Reset and then start the geometry app
2. Put 3 non collinear points anywhere on the plot area
3. Press shift/home settings
4. Set angle measure to degrees
5. press shift/symb setup
6. set angle measure to degrees
7. press plot
8. tap cmds/measure/angle
9. tap on A then press enter, repeat for B and C
10. observe the angel in the upper left corner in radians, not degrees
11. press Apps/Start
12. observe the angel in the upper left corner in degrees
13. repeat steps 8,9, and 10 and the angles all jump back to radians

I remember one of the Prime team saying something about it a long time ago. I'm thinking it must be hard to fix or they would have done it by now. Or maybe it's that way for a reason.

-road

[Joe Horn]

(04-05-2021 01:24 AM)roadrunner Wrote:  

(04-05-2021 12:36 AM)Joe Horn Wrote:  Does the above shed any light on the issue at hand?

I don't think that's the issue. Try these steps: ...

Aha, I see what you mean! The mode setting is still degrees, but the result is in radians. Most unfortunate.