Invalid Array Width without declaring new dimension - dc.js

Question

My web app is generating an "Invalid Array Width" error at line 462 of Crossfilter.js v1.3.12. This error seems to tell me I have >32 dimensions. The puzzle is that I am not knowingly declaring a new dimension when the error occurs.
I have 10 slider bars, which act as numeric filters on my dataset. At the end of a drag event on the second slider bar, a dimension is declared if none already exists at the second location within the numericDims array. (Edit: even when I declare all the 10 dimensions in advance, and remove the dynamic declaration, the problem still occurs.) About 10 dimensions already exist in the app for other graphics & filters.
The first time I move a slider handle, "new dimension" is logged. After that, every time I move a handle on the same slider, "new dimension" is not logged. This is expected behaviour. But if I move the handles enough times, I get the "Invalid Array Width" error. So, I think I must be accidentally declaring a new dimension every time I move a handle. Can anyone see how I am unwittingly declaring a new dimension? The most relevant code:
if (!numericDims[tempIndex]) {
console.log('new dimension');
numericDims[tempIndex] = facts.dimension(function(p){ return p[d]; });
}
if (flag==0) {
prt.classed("activeFilter",true);
numericDims[tempIndex].filterFunction(function(p){ return p>=min && p<=max; });
} else {
prt.classed("activeFilter",false);
numericDims[tempIndex].filterAll();
// numericDims[tempIndex].dispose(); ***I figure it's quicker to store them instead of disposing/deleting. Even when I dispose/delete, the problem still happens.
// delete numericDims[tempIndex];
// numericDims.splice(tempIndex,1);
prt.selectAll("g.handle.left").attr("title",null);
prt.selectAll("g.handle.right").attr("title",null);
}
console.log(numericDims);
Full function:
function dragended(d) {
let transformation = {
Y: Math.pow(10, 24),
Z: Math.pow(10, 21),
E: Math.pow(10, 18),
P: Math.pow(10, 15),
T: Math.pow(10, 12),
G: Math.pow(10, 9),
M: Math.pow(10, 6),
k: Math.pow(10, 3),
h: Math.pow(10, 2),
da: Math.pow(10, 1),
d: Math.pow(10, -1),
c: Math.pow(10, -2),
m: Math.pow(10, -3),
μ: Math.pow(10, -6),
n: Math.pow(10, -9),
p: Math.pow(10, -12),
f: Math.pow(10, -15),
a: Math.pow(10, -18),
z: Math.pow(10, -21),
y: Math.pow(10, -24)
}
let reverse = s => {
let returnValue;
Object.keys(transformation).some(k => {
if (s.indexOf(k) > 0) {
returnValue = parseFloat(s.split(k)[0]) * transformation[k];
return true;
}
})
return returnValue;
}
var facts = window.facts;
if (d3.select(this).attr("class").indexOf("left")==-1) { var otherHandle = 'left'; } else { var otherHandle = 'right'; }
d3.select(this).classed("dragging",false);
var filterFields = window.filterFields;
var tempIndex = filterFields[0].indexOf(d);
var min = filterFields[2][tempIndex];
var max = filterFields[3][tempIndex];
//console.log(min+', '+max);
var scale = filterFields[4][tempIndex];
var t = d3.transform(d3.select(this).attr("transform"));
var thisX = t.translate[0];
var flag=0;
var prt = d3.select("g#f_"+tempIndex);
var leftHandleX = d3.transform(prt.selectAll("g.handle.left").attr("transform")).translate[0];
var rightHandleX = d3.transform(prt.selectAll("g.handle.right").attr("transform")).translate[0];
var wid = prt.selectAll("g.axis").select("rect.numFilterBox").attr("width");
prt.selectAll("g.axis").select("rect.numFilterBox").attr("x",leftHandleX).attr("width",rightHandleX - leftHandleX);
var num = -1;
var pFlag = 0;
if (filterFields[3][tempIndex]<=1) { var fmt = d3.format('%'); pFlag=1; } else { var fmt = d3.format('4.3s'); }
if (otherHandle=='left') {
if (thisX>=300 && scale(min)==0) { flag=1; }
max = scale.invert(thisX);
if (isNaN(+fmt(max).trim())) {
if (pFlag==1) {
max = +fmt(max).substr(0,fmt(max).length-1)/100
} else {
max = reverse(fmt(max));
}
} else {
max = +fmt(max).trim();
}
prt.selectAll("g.handle.right").attr("title",function(d){ return 'The filtered maximum for '+filterFields[1][tempIndex]+' is '+max; });
} else {
if (thisX<=0 && scale(max)==300) { flag=1; }
min = scale.invert(thisX);
if (isNaN(+fmt(min).trim())) {
if (pFlag==1) {
min = +fmt(min).substr(0,fmt(min).length-1)/100
} else {
min = reverse(fmt(min));
}
} else {
min = +fmt(min).trim();
}
prt.selectAll("g.handle.left").attr("title",function(d){ return 'The filtered minimum for '+filterFields[1][tempIndex]+' is '+min; });
}
filterFields[2][tempIndex] = min;
filterFields[3][tempIndex] = max;
window.filterFields = filterFields;
if (!numericDims[tempIndex]) {
console.log('new dimension');
numericDims[tempIndex] = facts.dimension(function(p){ return p[d]; });
}
if (flag==0) {
prt.classed("activeFilter",true);
numericDims[tempIndex].filterFunction(function(p){ return p>=min && p<=max; });
} else {
prt.classed("activeFilter",false);
numericDims[tempIndex].filterAll();
// numericDims[tempIndex].dispose();
// delete numericDims[tempIndex];
// numericDims.splice(tempIndex,1);
prt.selectAll("g.handle.left").attr("title",null);
prt.selectAll("g.handle.right").attr("title",null);
}
console.log(numericDims);
update();
doHighlight();
window.dragFlag=1;
}