dimple-js/src/objects/chart/methods/_axisIndex.js

Dimple is an object-oriented API allowing you to create flexible axis-based charts using [d3.js](http://d3js.org "d3.js").

        // Copyright: 2015 AlignAlytics
        // License: "https://github.com/PMSI-AlignAlytics/dimple/blob/master/MIT-LICENSE.txt"
        // Source: /src/objects/chart/methods/_axisIndex.js
        // Return the ordinal value of the passed axis.  If an orientation is passed, return the order for the 
        // specific orientation, otherwise return the order from all axes.  Returns -1 if the passed axis isn't part of the collection
        this._axisIndex = function (axis, orientation) {

            var i = 0,
                axisCount = 0,
                index = -1;

            for (i = 0; i < this.axes.length; i += 1) {
                if (this.axes[i] === axis) {
                    index = axisCount;
                    break;
                }
                if (orientation === null || orientation === undefined || orientation[0] === this.axes[i].position[0]) {
                    axisCount += 1;
                }
            }

            return index;

        };