Function handleSingleValueOverlays

src/traces/histogram/calc.js:433–510

(gd, trace, pa, mainData, binAttr)

 * Returns the binSpec for the trace that sparked all this
 */
function handleSingleValueOverlays(gd, trace, pa, mainData, binAttr) {
    var fullLayout = gd._fullLayout;
    var overlaidTraceGroup = getConnectedHistograms(gd, trace);
    var pastThisTrace = false;
    var minSize = Infinity;
    var singleValuedTraces = [trace];
    var i, tracei, binOpts;

    // first collect all the:
    // - min bin size from all multi-valued traces
    // - single-valued traces
    for(i = 0; i < overlaidTraceGroup.length; i++) {
        tracei = overlaidTraceGroup[i];

        if(tracei === trace) {
            pastThisTrace = true;
        } else if(!pastThisTrace) {
            // This trace has already had its autobins calculated, so either:
            // - it is part of a bingroup
            // - it is NOT a single-valued trace
            binOpts = fullLayout._histogramBinOpts[tracei['_' + mainData + 'bingroup']];
            minSize = Math.min(minSize, binOpts.size || tracei[binAttr].size);
        } else {
            var resulti = calcAllAutoBins(gd, tracei, pa, mainData, true);
            var binSpeci = resulti[0];
            var isSingleValued = resulti[2];

            // so we can use this result when we get to tracei in the normal
            // course of events, mark it as done and put _pos0 back
            tracei['_' + mainData + 'autoBinFinished'] = 1;
            tracei['_' + mainData + 'pos0'] = resulti[1];

            if(isSingleValued) {
                singleValuedTraces.push(tracei);
            } else {
                minSize = Math.min(minSize, binSpeci.size);
            }
        }
    }

    // find the real data values for each single-valued trace
    // hunt through pos0 for the first valid value
    var dataVals = new Array(singleValuedTraces.length);
    for(i = 0; i < singleValuedTraces.length; i++) {
        var pos0 = singleValuedTraces[i]['_' + mainData + 'pos0'];
        for(var j = 0; j < pos0.length; j++) {
            if(pos0[j] !== undefined) {
                dataVals[i] = pos0[j];
                break;
            }
        }
    }

    // are ALL traces are single-valued? use the min difference between
    // all of their values (which defaults to 1 if there's still only one)
    if(!isFinite(minSize)) {
        minSize = Lib.distinctVals(dataVals).minDiff;
    }