Method selectAll

src/base/base-mixin.js:412–414

* Execute in scope d3 selectAll using the given selector and return d3 selection result. * * This function is **not chainable** since it does not return a chart instance; however the d3 * selection result can be chained to d3 function calls. * @see {@link https://github.com/d3/d3

(sel)

     * @returns {d3.selection}
     */
    selectAll (sel) {
        return this._root ? this._root.selectAll(sel) : null;
    }

    /**
     * Set the root SVGElement to either be an existing chart's root; or any valid [d3 single