custom d3 multi format time scale - get your own formats/intervals into axis

gistfile1.js

// array of [format string, useFormat]. formats are accessed in order, return true to use the format
// - this is the default - it pretty much just finds the smallest time period that's non-zero
var multiScale = d3.time.format.utc.multi([
	[".%L", function(d) { return d.getUTCMilliseconds(); }],
	[":%S", function(d) { return d.getUTCSeconds(); }],
	["%I:%M", function(d) { return d.getUTCMinutes(); }],
	["%I %p", function(d) { return d.getUTCHours(); }],
	["%a %d", function(d) { return d.getUTCDay() && d.getUTCDate() != 1; }],
	["%b %d", function(d) { return d.getUTCDate() != 1; }],
	["%B", function(d) { return d.getUTCMonth(); }],
	["%Y", function(){ return true }]
]);