Square Root Function

[Xmlspy]

Does anyone know if Leadwerks has a square root function for LUA?

 

EDIT:

sqrt is highlighted in blue, but it doesn't work.

 

The reason I want a square root function is to determine the distance between two points using xy positions and the good ol distance formula sqrt( (x2-x1)^2 + (y2-y1)^2 ). Since there is no square root function (that I have found) one workaround is to create two pivot points, give them the x and y positions of each point, then use pivotOne:GetDistance(pivotTwo).

[Rick]

http://lua-users.org/wiki/MathLibraryTutorial

[Xmlspy]

I'm still getting used to LUA, but I find this to be a bit weird because I really want to write Math:Sqrt because many functions are written in that way. I guess it will be math.sqrt for now. Thanks.

[Rick]

The functions in the link I provided are part of the lua language. The ones you see like, Math:Sqrt, are part of the Leadwerks library. Every language has some base functions/features they provide but then people can make libraries using that language. I'm not 100% sure why Josh felt the need to duplicate some of these built in functions that Lua already had.

[Naughty Alien]

...i think you should avoid that particular function, if purpose is to get distance for comparison.. then use of ((x2-x1)^2 + (y2-y1)^2) without Sqrt is as good as Sqrt, but much faster, especially because you using Lua..

[nick.ace]

That's a good point Naughty Alien, because from a machine standpoint, a Taylor series is usually used to compute more complex mathematical functions (not too sure about square root, but I would guess so).

 

Would it be much slower for Lua? I would suspect that since it is a built-in Lua function, the interpretation would call the machine code for computing a square root. I feel that the interpretation overhead wouldn't come close to the calculation time. I might be wrong about this though, I just like to learn about these things!