Create element at center of artboard, move to next artboard and repeat

Question

Hey All! I've been lurking around here for quite some time and i've always been able to find what i needed. Until now. =)
I'm writing a Javascript to create multiple rectangles on the center of the active artboard and then repeat for all remaining artboards. However, i'm getting hung up on how to shift focus to the next artboard. I've read about  "setActiveArtboardIndex();" but whenever i try to use this feature, i get the error "setActiveArtboardIndex(); is not a function".
Here's the code i'm working with. Could anyone please tell me how to get the loop to switch to the next artboard before creating the next set of color blocks?
//Beginning of Script
#target illustrator
if (app.documents.length > 0) {
var docRef = app.activeDocument
else {
alert("No Document Open");
//Add Color Block Layer
artLayers.locked = true;
function existBlockLayer(layers, name) {
    for (i=0; i<docRef.layers.length; i++){
        if (layers[i].name===name) return true;
    return false;
if (existBlockLayer(docRef.layers,"Color Blocks")) {
    var removeLayer = artLayers.getByName("Color Blocks");
    removeLayer.locked = false;
    removeLayer.remove();
    var blockLayer = docRef.layers.add();
    blockLayer.name = "Color Blocks"
else {
    var blockLayer = docRef.layers.add();
    blockLayer.name = "Color Blocks"
blockLayer.locked = false;
//Get Document Swatches
var swatchList = docRef.swatches;
var artLayers = docRef.layers
var aB = docRef.artboards
var colorList = [];
for(var k=0; k< swatchList.length; k++) {
    if (swatchList[k].name.toLowerCase() != "thru-cut" && swatchList[k].name.toLowerCase() != "[registration]"//
    && swatchList[k].name.toLowerCase() != "[none]" && swatchList[k].name.toLowerCase() != "cut line"){
       colorList.push(swatchList[k].name);
//Create 1 Color Block per Swatch and Apply Swatch
for (var a=0; a<aB.length; a++) {
    var aBLeft = aB[a].artboardRect[0];
    var aBRight = aB[a].artboardRect[2]
    var aBTop = aB[a].artboardRect[1]
    var aBBottom = aB[a].artboardRect[3]
    var W = (aBRight/2);
    var H = (aBBottom/2);
    var posH = (H/2);
    var posW = (W/2);
    alert(W + " width " + H + " height");
    var activeArtboard = aB[a];
    //var aBPlus = setActiveArtboardIndex(a);
    for(var c=0,len=colorList.length;c<len;c++){
        var newBlock = docRef.pathItems.rectangle(posH, posW,10,10);
        newBlock.stroked = false;
    for (var i=0; i < colorList.length; i++) {
        docRef.pathItems[i].fillColor=docRef.swatches.getByName(colorList[i]).color;
artLayers.locked = false;
blockLayer.zOrder (ZOrderMethod.SENDTOBACK);
blockLayer.locked = true;
Thanks in advance all!

Answer 1

woah... ok. so what  you posted didn't really work (i had made a revision to that part of the code after my initial post. i realized i was dividing by two twice, so i removed one of those. as a result, i had to remove this "var posW = aBLeft+(aBRight + aBLeft)/2" and i had to add the right edge and left edge instead of subtracting).. but i removed some stuff and switched my variables and now it does work. this is what i ended up doing
for (var a=0; a<aB.length; a++) {
    var aBLeft = aB[a].artboardRect[0];
    var aBRight = aB[a].artboardRect[2]
    var aBTop = aB[a].artboardRect[1]
    var aBBottom = aB[a].artboardRect[3]
    var posH = (aBRight+aBLeft)/2;
    var posW = (aBBottom+aBTop)/2;
    var activeArtboard = aB[a];
    docRef.rulerOrigin[aBLeft, aBTop]
    aB.setActiveArtboardIndex(a);
    makeBlocks();
So.. i'm really glad that it's working.. but i don't really know why it is.. as has been the bane of my existence as a self teaching coder.. if you have a moment, could you explain what's different about my part and your correction? I'm sure something like that will come up again in the future and i'd love to know where i went wrong. =)
I really really appreciate your help, kind friend. pixxxel schubser
Oh and one more thing, if you could. Is there a cleaner way for me to negate those certain swatches? I know i can put them in an array,  but it doesn't seem to work when it comes time to say "if swatchList[k].name != [array of colors not to use]". I'd like this thing to be as nice and clean as possible when i surprise my boss with it.. Almost like it looks like i knew what i was doing.