Math.cos Math.sin = Math.HELP

Question

Hello Everyone,
I was hoping to create a JS script to move objects away from common center based upon their current position. I was thinking to use a single selected path item as the center based on its position x/y and width/height. Using this reference point the script would then move away all other path items from this center point based on a desired amount and with uniform increments given their current location from this center. I was thinking cos and sin would be my friend in this case, however they seem to have become my foe instead. ;-)
Does this sound doable? What am I missing, doing wrong, misinterpreting? Below is a non-working attempt, I can't seem to sort things out, perhaps I was close and missed it or maybe I am super way off and its more complex than I thought. However at this point I am confused across my various failed attempts this only being one of them.
Thanks in advance for any assistance and sanity anyone can provide.
// Example failed code, nonworking concept
var docID = app.activeDocument;
var s0 = docID.selection[0];
pID = docID.pathItems;
var xn, yn;
var stepNum = 20;
for (var i = 0; i < pID.length; i++) {
    var p = pID[i];
    var dx = ((s0.position[0] + s0.width) / 2 - (p.position[0] + p.width) / 2);
    var dy = ((s0.position[1] + s0.height) / 2 - (p.position[1] + p.height) / 2);
    xn = Math.cos(Number(dx) * Math.PI / 180)+stepNum;
    yn = Math.sin(Number(dy) * Math.PI / 180)+stepNum;
    var moveMatrix = app.getTranslationMatrix(xn, yn);
    p.transform(moveMatrix);
    stepNum+=stepNum;

Answer 1

Hi W_J_T, here's one way to do what I think you want to do, I commented out the step increment so all items will "explode" the same distance, not sure if that's what you need.
first I'd move the calculation of the Selected object's center out of the loop, you only need to make the math once.
also, (s0.position[0] + s0.width) / 2  has a problem, it will not give you the center, check below
// calculate Selection center position
var cx = s0.position[0] + s0.width/2;
var cy = s0.position[1] + s0.height/2;
then we're going to loop thru all items and calculate their center
        // calculate pathItem's center position
        var px = p.position[0] + p.width/2;
        var py = p.position[1] + p.height/2;
we're going to skip calculating the distance from the selection's center to each item's center, we don't need it for this method, other methods could use this info.
now, your actual question about Sin/Cos
xn = Math.cos(Number(dx) * Math.PI / 180)+stepNum;
sin(angle) and cos(angle) expect angles in Radians, you are not providing any angles in the formula above. We need to calculate the angle between Selection's center and each path's center
        // get the angle formed between selection's center and current path's center
        var angle = get2pointAngle ([cx,cy], [px,py]);
once we have the angle we can apply it to our "Explosion" variable, I'm assuming is stepNum, and get its x and y distance it needs to move away from selection
        // the distance to move is "stepNum" in the same direction as the angle found previously, get x and y vectors
        var dx = stepNum*Math.cos(angle);// distance x
        var dy = stepNum*Math.sin(angle);// distance y
all is left to do is move the paths, here's the whole thing
// Explosion, AKA move all items away from selection
// carlos canto
// http://forums.adobe.com/thread/1382853?tstart=0
var docID = app.activeDocument;
var s0 = docID.selection[0];
pID = docID.pathItems;
var stepNum = 20; // this is the distance to "explode"
// calculate Selection center position
var cx = s0.position[0] + s0.width/2;
var cy = s0.position[1] + s0.height/2;
for (var i = 0; i < pID.length; i++) {
    var p = pID[i];
    // skip selected item
    if (!p.selected) {
        // calculate pathItem's center position
        var px = p.position[0] + p.width/2;
        var py = p.position[1] + p.height/2;
        // get the angle formed between selection's center and current path's center
        var angle = get2pointAngle ([cx,cy], [px,py]);
        // the distance to move is "stepNum" in the same direction as the angle found previously, get x and y vectors
        var dx = stepNum*Math.cos(angle);// distance x
        var dy = stepNum*Math.sin(angle);// distance y
        var moveMatrix = app.getTranslationMatrix(dx, dy);
        p.transform(moveMatrix);
        //stepNum+=stepNum;
// return the angle from p1 to p2 in Radians. p1 is the origin, p2 rotates around p1
function get2pointAngle(p1, p2) {
    var angl = Math.atan2(p2[1] - p1[1], p2[0] - p1[0]);
    if (angl<0) {   // atan2 returns angles from 0 to Pi, if angle is negative it means is over 180 deg or over Pi, add 360 deg or 2Pi, to get the absolute Positive angle from 0-360 deg
        angl = angl + 2*Math.PI;
  return angl;