for (var i = 0; i < ticks.length; i++) {
// TODO(danvk): allow secondary axes to draw a grid, too.
if (ticks[i][0] != 0) continue;
for (var i = 0; i < ticks.length; i++) {
// TODO(danvk): allow secondary axes to draw a grid, too.
if (ticks[i][0] != 0) continue;