main_x.domain([
    d3.min(data.result, function(d) { return d.date.setDate(d.date.getDate() - 1); }),
    d3.max(data.result, function(d) { return d.date.setDate(d.date.getDate() + 2); })
]);

function brushed() {

    // I thought that re-defining the x domain without the date manipulations might work, but I
    // was getting some odd results
    //main_x.domain(d3.extent(data.result, function(d) { return d.date; }));

    main_x.domain(brush.empty() ? main_x.domain() : brush.extent());
    console.log(brush.extent());

    bar.selectAll("rect")
        .attr("width", function(d) { return main_width/len; })
        .attr("x", function(d) { return main_x(d.date) - (main_width/len)/2; });

    main.select(".x.axis").call(main_xAxis);
}