LUA Progress bar

[FrederikTheisen]

Hi there

I'm working on a project where I need to find the distance between up to 2000 points in 3D space.
It takes a lot of time on the nSpire CX calculator, so I wanted to make a progress bar, showing how far it was in the process.

Here is the code for the loading:

Code: Select all

function getMaxDist()
   maxDist = 0
   for i = 1,molTable["nAtoms"] do
      for j = 1,molTable["nAtoms"] do
         local dist = math.sqrt((molTable[i]["x"] - molTable[j]["x"])^2  +  (molTable[i]["y"] - molTable[j]["y"])^2  +  (molTable[i]["z"] - molTable[j]["z"])^2)
         if dist > maxDist then
            maxDist = dist
         end
      end
   end
end

It's not finished, but you get the idea.

But I'm not able to update the screen while I'm inside the loop.
It only updates once it has finished.

Is there any possible way to make a loading bar in LUA on the nSpire CX?

regards
Frederik

[Ti64CLi++]

I don't know.
Why will you do a progress bar?

[Bisam]

1) Ton algorithme de recherche est inefficace : tu fais 2 fois plus de boulot que nécessaire. Tu peux t'arrêter à j = i-1 dans ta 2ème boucle puisque la distance de i à j est la même que celle de j à i.
2) Tu devrais localiser les fonctions que tu utilises souvent, comme la fonction "math.sqrt".
3) Encore mieux, tu devrais créer une fonction qui renvoie la distance entre 2 atomes, directement...

1) Your search algorithm is inefficient : you work twice as needed. You can stop your second loop at j=i-1 as the distance between i and j is the same as the distance between j and i.
2) You should localize the functions used very often, as for "math.sqrt".
3) Even better, you should create a function returning the distance between 2 atoms, directly...

[Ti64CLi++]

Salut Bisam
pourquoi parle-tu en français alors qu'il ne comprends peut-être pas le français.

[Bisam]

J'ai répondu en français ET en anglais...

[Ti64CLi++]

Je ne vois pas d'anglais pourtant.

[Bisam]

Regarde mieux !

[Ti64CLi++]

a oui mais mon ordinateur bug et donc des fois il cache les liens.

[Jens_K]

Hi, I once messed around with progressbars using coroutines. I tried to use that principle with your algorithm (and I optimized it a bit ) and it seems to work:

Code: Select all

function getMaxDist()
   local sqrt = math.sqrt
   local maxDist = 0
   local dist
   local nAtoms = molTable["nAtoms"]
   for i = 1,nAtoms-1 do
      for j = i+1,nAtoms do
         dist = sqrt((molTable[i]["x"] - molTable[j]["x"])^2  +  (molTable[i]["y"] - molTable[j]["y"])^2  +  (molTable[i]["z"] - molTable[j]["z"])^2)
         if dist > maxDist then
            maxDist = dist
         end
      end
      coroutine.yield(i/(nAtoms-1))
   end
end

CRgetMaxDist=coroutine.create(getMaxDist)
local progress=0
local finished=false

timer.start(0.01)
function on.timer()
    platform.window:invalidate()
    _, progress = coroutine.resume(CRgetMaxDist)
    if progress==1 then
        timer.stop()
        finished=true
    end
end

function on.paint(gc)
    if finished then
        gc:drawString("finished",50,50)
    else
        gc:fillRect(0,100,318*progress,10)
    end
end

Edit: It's now optimized, so that it measures the distanced between the same 2 points only once

[FrederikTheisen]

Wow, thanks a bunch!
I'm going to work on this once I get home.

I know that the code is not optimized (not checking double will be a nice fix for sure).
Though many o the constants are declared (as local) outside the code snippet i shared (program is currently 700 lines + 8000 lines database)

I'm not familiar with the coroutine 'function', but I hope that it will address the problem.