How to simulate 'INV' or 'TAN ^ -1'...?

[Burgs]

Greetings,

  I have a need to use a Tan function to a power of "-1".  On a calculator this is normally the "INV" key or possibly the "2nd" key.  The "Tan ^ -1" should return a value in degrees.  This seems to not be exactly possible using AutoIT.  Here is a sample script:

 

#include <MsgBoxConstants.au3>
#include <Math.au3>

Local $_value = .25
ConsoleWrite("tan convert to degrees value is: " & _Degree(Tan($_value)) & @CRLF)  ;returns 14.63   *....SEEMS CLOSE...*  should be 14.036

And I also attempted:

ConsoleWrite("inverse tan of value is: " & Tan($_value) ^ -1 & @CRLF)  ;returns 3.916 however should be 14.036 
ConsoleWrite("inverse tan of value is: " & _Degree(Tan($_value) ^ -1) & @CRLF)  ;returns 224.388 however should be 14.036
ConsoleWrite("inverse tan of value is: " & (Tan ^ -1) * ($_value) & @CRLF)  ;returns 1.#INF

As can be seen in the code...the closest answer (from what I get on a calculator) is "14.63"...when the calculator indicates it should be "14.036"...is there some reason for the discrepancy?  Is simulation of a "INV" or "2nd" key on the calculator possible using AutoIT?  I thank you in advance for any suggestion.   

[ahmet]

Try with ATan(). I think this function is mentioned in the helpfile for Tan function, under Related functions.

[jchd]

3 hours ago, Burgs said:

_Degree(Tan($_value))

This doesn't make sense! Tan($x) is a scalar value, not an angle.

As @ahmet just said, you need ATan($x)

[Burgs]

Thanks to both of you that replied.  I have attempted the ATan function, however I am seeing a value returned of "0.244978663126864", which is not what my Windows 11 calculator is returning (using '2nd' and 'Tan ^ -1').

Sorry about the "Degree(Tan($_value))" I mis-read the documentation and thought the value was returned in radians and I wanted to convert to degrees...however I see the INPUT is in radians. 

I am trying to reproduce the values in this information, "https://www.usgs.gov/educational-resources/determine-percent-slope-and-angle-slope".  Specifically the information located in the second part of the page beginning at "Angle of Slope" in a bold font.

 

 

[Melba23]

Burgs,

These are my results for Tan-1(.25) in radians:

• AutoIt ATan function:                  0.244978663126864
• My Sharp scientific calculator:  0.24497866
• My Windows 10 calculator:        0.24497866312686415417208248121128

The 26.5 degrees mentioned for ATan(.5) on the page to which you linked is obviously floored from the actual value of 26.565051. All 3 methods mentioned above match to 6 decimal places.

Do you still have a problem?

M23

[Burgs]

Thanks for your input Melba, I think I have it now...just need to convert those results to degrees, which the calculator did automatically.  I am old also...hahaha .  Regards to you and the others that replied.