I need help with absolute values!

[Fourex]

Specifically, this snippet of code. :

Code: Select all

Axvel = Axvel + ((Mx - Ax) / sqrt(abs((Mx-Ax)^2 + (My-Ay)^2))) * (Aacc / (sqrt(abs((Mx-Ax)^2 + (My-Ay)^2)))^2) * dt

FYI, Axvel, Mx, Ax, My, Ay, and Aacc are variables. And,

Ax = 100
Ay = 100
Axvel = 0
Aacc = 30
Mx = 0
My = 0

When I try to run the script this is in I get the ERROR! message "main.lua:43: attempt to call global 'abs' (a nil value)" (the line above is line 43)
Am I correct it assuming "abs()" is an absolute value function?
Can anyone help me? Thanks in advance!

This is the full code:

Code: Select all

function load()

	font = love.graphics.newFont(love.default_font, 12)
    love.graphics.setFont(font)

	Aball = love.graphics.newImage("greenball.png")
	Bball = love.graphics.newImage("pinkball.png")
	
	--Aball
	Ax = 100
	Ay = 100
	Axvel = 0
	Ayvel = 20
	
	Aacc = 30
	Afric = .99
	
	-- Bball
	Bx = 300
	By = 300
	
	Bxvel = 20
	Byvel = 0
	
	Bacc = .2
	Bfric = .999
	
	-- Mouse
	Mx = 0
	My = 0
	
end

function update(dt)
	
	-- Mouse
		Mx , My = love.mouse.getPosition() 
	
	-- Aball
		--Axvel = Axvel + (((Bx - Ax) * Aacc) * dt)
		--Ayvel = Ayvel + (((By - Ay) * Aacc) * dt)
		
		Axvel = Axvel + ((Mx - Ax) / sqrt(abs((Mx-Ax)^2 + (My-Ay)^2))) * (Aacc / (sqrt(abs((Mx-Ax)^2 + (My-Ay)^2)))^2) * dt
		Ayvel = Ayvel + ((MY - AY) / sqrt(abs((Mx-Ax)^2 + (My-Ay)^2))) * (Aacc / (sqrt(abs((Mx-Ax)^2 + (My-Ay)^2)))^2) * dt
		
		Axvel = Axvel * Afric
		Ayvel = Ayvel * Afric
		
	-- Bball
		Bxvel = Bxvel + (((Ax - Bx) * Bacc) * dt)
		Byvel = Byvel + (((Ay - By) * Bacc) * dt)
	
		Bxvel = Bxvel + (((Mx - Bx) * Bacc) * dt)
		Byvel = Byvel + (((My - By) * Bacc) * dt)
			
		Bxvel = Bxvel * Bfric
		Byvel = Byvel * Bfric
	
	if love.keyboard.isDown(love.key_space) then
	Axvel = 0
	Ayvel = 0
	Bxvel = 0
	Byvel = 0
	
	Ax = 100
	Ay = 100
	
	Bx = 300
	By = 300
	end
	
	Ax = Ax + Axvel
	Ay = Ay + Ayvel
	
	--Bx = Bx + Bxvel
	--By = By + Byvel
	
	
	
end

function draw()

	-- balls
	love.graphics.draw(Bball, Bx, By)
	love.graphics.draw(Aball, Ax, Ay)
	-- mouse
	love.graphics.draw("mouse", Mx, My)
	-- x coordinates
	love.graphics.draw("000", 0, 10)
	love.graphics.draw("100", 100, 10)
	love.graphics.draw("200", 200, 10)
	love.graphics.draw("300", 300, 10)
	love.graphics.draw("400", 400, 10)
	love.graphics.draw("500", 500, 10)
	love.graphics.draw("600", 600, 10)
	love.graphics.draw("700", 700, 10)
	love.graphics.draw("800", 800, 10)
end

[bartbes]

It's math.abs.

[Fourex]

*sigh* it seems like all of the problems I have with love are so simple to fix... I guess that's a good thing though.