c3_chart_internal_fn.getYDomain = function()

in TestApplications/Web/js/lib/components/c3-0.4.2/c3.js [1298:1381]
74 lines of code
39 McCabe index (conditional complexity)

    c3_chart_internal_fn.getYDomain = function (targets, axisId, xDomain) {
        var $$ = this, config = $$.config,
            targetsByAxisId = targets.filter(function (t) { return $$.getAxisId(t.id) === axisId; }),
            yTargets = xDomain ? $$.filterByXDomain(targetsByAxisId, xDomain) : targetsByAxisId,
            yMin = axisId === 'y2' ? config.axis_y2_min : config.axis_y_min,
            yMax = axisId === 'y2' ? config.axis_y2_max : config.axis_y_max,
            yDomainMin = isValue(yMin) ? yMin : $$.getYDomainMin(yTargets),
            yDomainMax = isValue(yMax) ? yMax : $$.getYDomainMax(yTargets),
            domainLength, padding, padding_top, padding_bottom,
            center = axisId === 'y2' ? config.axis_y2_center : config.axis_y_center,
            yDomainAbs, lengths, diff, ratio, isAllPositive, isAllNegative,
            isZeroBased = ($$.hasType('bar', yTargets) && config.bar_zerobased) || ($$.hasType('area', yTargets) && config.area_zerobased),
            showHorizontalDataLabel = $$.hasDataLabel() && config.axis_rotated,
            showVerticalDataLabel = $$.hasDataLabel() && !config.axis_rotated;

        if (yDomainMax < yDomainMin) {
            if (isValue(yMin)) {
                yDomainMax = yDomainMin + 10; // TODO: introduce axis.y.maxMin
            } else {
                yDomainMin = yDomainMax - 10; // TODO: introduce axis.y.minMax
            }
        }

        if (yTargets.length === 0) { // use current domain if target of axisId is none
            return axisId === 'y2' ? $$.y2.domain() : $$.y.domain();
        }
        if (isNaN(yDomainMin)) { // set minimum to zero when not number
            yDomainMin = 0;
        }
        if (isNaN(yDomainMax)) { // set maximum to have same value as yDomainMin
            yDomainMax = yDomainMin;
        }
        if (yDomainMin === yDomainMax) {
            yDomainMin < 0 ? yDomainMax = 0 : yDomainMin = 0;
        }
        isAllPositive = yDomainMin >= 0 && yDomainMax >= 0;
        isAllNegative = yDomainMin <= 0 && yDomainMax <= 0;

        // Cancel zerobased if axis_*_min / axis_*_max specified
        if ((isValue(yMin) && isAllPositive) || (isValue(yMax) && isAllNegative)) {
            isZeroBased = false;
        }

        // Bar/Area chart should be 0-based if all positive|negative
        if (isZeroBased) {
            if (isAllPositive) { yDomainMin = 0; }
            if (isAllNegative) { yDomainMax = 0; }
        }

        domainLength = Math.abs(yDomainMax - yDomainMin);
        padding = padding_top = padding_bottom = domainLength * 0.1;

        if (center) {
            yDomainAbs = Math.max(Math.abs(yDomainMin), Math.abs(yDomainMax));
            yDomainMax = yDomainAbs - center;
            yDomainMin = center - yDomainAbs;
        }
        // add padding for data label
        if (showHorizontalDataLabel) {
            lengths = $$.getDataLabelLength(yDomainMin, yDomainMax, axisId, 'width');
            diff = diffDomain($$.y.range());
            ratio = [lengths[0] / diff, lengths[1] / diff];
            padding_top += domainLength * (ratio[1] / (1 - ratio[0] - ratio[1]));
            padding_bottom += domainLength * (ratio[0] / (1 - ratio[0] - ratio[1]));
        } else if (showVerticalDataLabel) {
            lengths = $$.getDataLabelLength(yDomainMin, yDomainMax, axisId, 'height');
            padding_top += lengths[1];
            padding_bottom += lengths[0];
        }
        if (axisId === 'y' && notEmpty(config.axis_y_padding)) {
            padding_top = $$.getAxisPadding(config.axis_y_padding, 'top', padding, domainLength);
            padding_bottom = $$.getAxisPadding(config.axis_y_padding, 'bottom', padding, domainLength);
        }
        if (axisId === 'y2' && notEmpty(config.axis_y2_padding)) {
            padding_top = $$.getAxisPadding(config.axis_y2_padding, 'top', padding, domainLength);
            padding_bottom = $$.getAxisPadding(config.axis_y2_padding, 'bottom', padding, domainLength);
        }
        // Bar/Area chart should be 0-based if all positive|negative
        if (isZeroBased) {
            if (isAllPositive) { padding_bottom = yDomainMin; }
            if (isAllNegative) { padding_top = -yDomainMax; }
        }
        return [yDomainMin - padding_bottom, yDomainMax + padding_top];
    };