Formula - Printable Version

Formula - Printable Version

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Pages: 1 2

Formula - Chris - 10-02-2024

Hello
How to write this line so that the result is in degrees.
I# = ASIN(F# * SIN(H#))

Chris

RE: Formula - bplus - 10-02-2024

I# = _R2D(ASIN(F# * SIN(H#)))

_R2D() is built in function to convert radians to degrees

vise versa is _D2R()

RE: Formula - Chris - 10-02-2024

I# = _R2D(ASIN(F# * SIN(H#)))
Gives error. From what version of QB64 _R2D is valid.

RE: Formula - bplus - 10-02-2024

(10-02-2024, 08:16 PM)Chris Wrote: I# = _R2D(ASIN(F# * SIN(H#)))
Gives error. From what version of QB64 _R2D is valid.

QB64pe of course, QB64 should work with this as well.

You probably need _Asin() not Asin() or to get QB64pe Big Grin

RE: Formula - SMcNeill - 10-02-2024

(10-02-2024, 08:16 PM)Chris Wrote: I# = _R2D(ASIN(F# * SIN(H#)))
Gives error. From what version of QB64 _R2D is valid.

If only there was some source of reference information which one might could use to look up information like that... Perhaps, something... like a wiki??

Big Grin

https://qb64phoenix.com/qb64wiki/index.php/R2D

Quote:Availability
QB64 v1.0 and up

QB64-PE all versions

I'd say the issue is the lack of underline with the _ASIN command.

Honestly, I do recommend the wiki for looking up syntax and examples for stuff like this. There's a reason why we go through so much effort to document these things for the user base, you know. Wink

RE: Formula - Chris - 10-02-2024

It doesn't work in QB64pe either. Maybe someone who uses trigonometry will chime in

RE: Formula - bplus - 10-02-2024

It works fine!

Code: (Select All)
For a = 0 To _Pi(2) Step _Pi(2 / 18) ' stepping 20 degrees

    Print Int(_R2D(a) + .001); ' convert to rounded up integer

Next

RE: Formula - bplus - 10-02-2024

You know what! I wonder about the _ASin() function, it looks funky!!!

Code: (Select All)
For a = 0 To _Pi(2) Step _Pi(2 / 18) ' stepping 20 degrees

    Print Int(_R2D(a) + .001);

    sina = Sin(a)

    Print Int(_R2D(_Asin(sina)) + .001)

Next

Filename: Funky _Asin.PNG Size: 21.39 KB 10-02-2024, 09:31 PM

RE: Formula - SMcNeill - 10-02-2024

Are you expecting F# and H# to be in degrees as well?

Code: (Select All)

I# = _R2D(_Asin(_D2R(F#) * Sin(_D2R(H#))))

Out of the above, which is radian? Which is degree?

What is the value for F#? Is it 0 to 2 * _Pi? Or is it 0 to 360?
Same for H#.

And what do you expect back for I#?

Plug and play those commands into your formula until you get the degrees where you want them and the radians where you need them.

RE: Formula - SMcNeill - 10-02-2024

(10-02-2024, 09:28 PM)bplus Wrote: You know what! I wonder about the _ASin() function, it looks funky!!!

Code: (Select All)
For a = 0 To _Pi(2) Step _Pi(2 / 18) ' stepping 20 degrees Print Int(_R2D(a) + .001); sina = Sin(a) Print Int(_R2D(_Asin(sina)) + .001) Next

What's funky about it? The curve goes up, then down, then up...

[Image: sinegraph2.png]