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Trigonometric Functions, Degrees and cas - Printable Version

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Trigonometric Functions, Degrees and cas - Arno K - 07-17-2015 04:21 PM

Today I entered sin(22.5°) in cas-mode, angle-mode is radians, to check if it provides the intended solution, 1/2*sqrt(2-sqrt(2)). Instead it delivered: sin(22.5*°), using deg from convert didn't help either, sin(45/2) was not better. Clearly with sin(45*PI/360) it worked, so I think this is another bug in the Prime, interoperation between the cas and other parts of the OS is concerned.
Arno


RE: Trigonometric Functions, Degrees and cas - roadrunner - 07-17-2015 06:47 PM

That's nothing, I tried converting 1_deg to radians and got the correct number, 0.0174 but instead of the expected _rad unit I got 1.74532925199e−2_譕诬Ѝ抹嘁疋(ၶᯨ�ᑵ事ꄐ뤄Ţ痿0౵ҍֈඤ

Don't believe me? Here's the screen shot:

[attachment=2340]


Smile

Road


RE: Trigonometric Functions, Degrees and cas - Marcel - 07-17-2015 07:14 PM

Hi,
In CAS mode, this make my Prime reboot!
Marcel.


RE: Trigonometric Functions, Degrees and cas - parisse - 07-17-2015 08:28 PM

I just tried convert(1_deg,_rad) and I get 1.74...e-2_rad. Make sure to type convert in lowercase.
If you want to use ° inside CAS, just do that
°:=pi/180
Or run sin(45/2*pi/180)


RE: Trigonometric Functions, Degrees and cas - Arno K - 07-17-2015 08:28 PM

(07-17-2015 06:47 PM)roadrunner Wrote:  0.0174 but instead of the expected _rad unit I got 1.74532925199e−2_譕诬Ѝ抹嘁疋(ၶᯨ�ᑵ事ꄐ뤄Ţ痿0౵ҍֈඤ
Don't believe me? Here's the screen shot:
Road
at least the number is correct, sometimes I wish me a 50G with the speed, the form-factor and the display of the Prime. In other words: Everytime I do something I come to the point I find some new "difficulties" hidden in the Prime which my program on the mobile and on the pc don't have, but as the Prime was too expensive to be kept in the drawer..., and somehow I like it.
Arno


RE: Trigonometric Functions, Degrees and cas - roadrunner - 07-17-2015 08:35 PM

Hi Marcel,

I think I figured it out.

Typing convert in lower case works in cas: convert(1_(deg),1_(rad))

Using the sto soft button works in cas: 1_(deg)▶_(rad) but don't type a number before _rad.

Using the built-in menu item shift/units/tools/CONVERT or typing CONVERT (upper case) in CAS doesn't work but does work in home and rpn.


RE: Trigonometric Functions, Degrees and cas - roadrunner - 07-17-2015 08:39 PM

Hi Arno,

The prime is an awesome machine. Software bugs are to be expected. They'll work them out eventually.

Road


RE: Trigonometric Functions, Degrees and cas - Marcel - 07-17-2015 10:10 PM

Hi!
Sorry, I used the CONVERT (upper case) in CAS mode and not the convert (lower case) !

In fact, to be an expert with the Prime, we have to use it a lot!

I do a lot of programming (Astro Lab) for the past two months ... now I will return to the basic!

Marcel