Inverse trigonometric functions notation


(Aris Nikolopoulos) #1

Hi everyone,

simple question:
I couldn’t find the notation for

  • arccotangent
  • arcsine
  • arccosine
  • and cotangent

in expression does anybody know how you type them?
I couldn’t even find them in the provided list.
thanks.


(David Rutten) #2

You get Acos, Asin, Atan, and Atan2, more are not available.


(Aris Nikolopoulos) #3

not even cotangent?
it’s no big deal, you can put the complementary of course but it adds a level of complexity.
could you please put it in next release?
thanks.


(Laurent Delrieu) #4

Hello
am I dumb or atan disapeared for me ?


image
image
image


(qythium) #5

I think it’s pretty standard among math programming libraries to only provide sin, cos, and tan along with their inverses, everything else can be derived easily from those three.

cot(θ) = 1/tan(θ)
acot(x) = atan(1/x)

Your expression can be simplified to
image


(Aris Nikolopoulos) #6

still, you have to admit you were thinking for about 5 mins hehehe
anyway thank you. I will use it.
and I will try to make my expressions ‘cleaner’ in the future :smile:


(qythium) #7

I got distracted looking up the wiki page for historical trig functions and deciding whether to include this screenshot :stuck_out_tongue:

And it gets worse down the page:


(David Rutten) #8

Could still be both of course. But it seems to be gone here too. Very strange.


(Aris Nikolopoulos) #9

good think about this forum: people always help you with your problem.
bad think about this forum: people always distract you with interesting things :smile:


(David Rutten) #10

The expression language in GH1 was modelled on VBScript. It has very limited support for everything. In GH2 the expressions can be typed in C# and VB (and, presumably, Python) and the aim is to provide a much richer mathematical toolset both to expressions and as regular components.


(David Rutten) #11

Yeah, found the issue, turns out it was me who was dumb.