piano keyboard help

[randomperson#5]

hi...someone pleasee help me.... i'm desperate!! i'm making this piano keyboard program, it kind of works, but the program keeps crashing, and says "variable has no value".

code:

%Some random parts of my code var notes : array 1 .. 53 of string procedure processPlay     for x : 1 .. totalInput         play (notes (x)) %variable has no value     end for end processPlay procedure userInput         for i : 1 .. 53         buttonwait ("down", rangex, rangey, button, buttonupdown)         for x : 0 .. 120 by 30             if rangex >= 0 + x and rangex <= 30 + x and rangey >= 470 and rangey <= 500 then                 if x = 0 then                     notes (i) := "1"                 elsif x = 30 then                     notes (i) := "2"........... (continues)     if rangex >= 630 and rangex <= 665 and rangey >= 80 and rangey <= 100 then % play btn             finished := true         end if         totalInput := i         exit when finished     end for processPlay end userInput

any help will be greatly appreciated!!

[TheOneTrueGod]

First of all, don't double post.

Second of all, read the [Turing FAQ] (Top of the help page)

[Cervantes]

I'm not seeing why that's causing a 'variable has no value' error just from the code you gave us.

Is it possible that you are calling 'processPlay' without having called 'userInput'? That would do it (unless you initialized totalInput to equal 0, which you should have).

This code can definately be cleaned up. You should look into parameters. Global variables are a bad way to go. Check out the Turing Walkthrough for a link to the tutorial on procedures and functions or check out the Turing Help file under 'prcoedure', 'function', and 'param...'

randomperson#5 wrote:

if x = 0 then
notes (i) := "1"
elsif x = 30 then
notes (i) := "2"........... (continues)

Do you see a pattern here? There's no need to have a giant if structure for this. Even if you did need to do it with conditionals like this, you'd use a case statement.

But we can still do better. Try this:

code:

notes (i) := ceil ((x + 1) / 30)

'ceil' is a function that rounds up to the nearest integer.
But that's not quite right, is it. That's assigned an integer to 'notes (i)'. We want to give it a string. Easy enough: we can type cast it, using 'intstr'.

code:

notes (i) := intstr (ceil ((x + 1) / 30))

[Clayton]

or if you dont understand where that came from you could use some kind of a nested for loop, also, i think that maybe one of your if conditions is wrong, so if one of them doesnt work (mainly the ones that give the variables values) then the variables dont get a value and your processPlay is called with no value to the variables