d3.matcher(selector) Given the specified selector, returns a function which returns true if this element matches the specified selector. This method is used internally by selection.filter. For example, this: var div = selection.filter("div"); Is equivalent to: var div = selection.filter(d3.matcher("div")); (Although D3 is not a compatibility layer, this implementation does support vendor-prefixed implementations due to the recent standardization of element.matches.)

d3.map([object[, key]]) Constructs a new map. If object is specified, copies all enumerable properties from the specified object into this map. The specified object may also be an array or another map. An optional key function may be specified to compute the key for each value in the array. For example: var map = d3.map([{name: "foo"}, {name: "bar"}], function(d) { return d.name; }); map.get("foo"); // {"name": "foo"} map.get("bar"); // {"name": "bar"} map.get("baz"); // undefined See also ne

d3.local() Declares a new local variable. For example: var foo = d3.local(); Like var, each local is a distinct symbolic reference; unlike var, the value of each local is also scoped by the DOM.

d3.line() Constructs a new line generator with the default settings.

d3.lab(l, a, b[, opacity]) d3.lab(specifier) d3.lab(color) Constructs a new Lab color. The channel values are exposed as l, a and b properties on the returned instance. Use the Lab color picker to explore this color space. If l, a and b are specified, these represent the channel values of the returned color; an opacity may also be specified. If a CSS Color Module Level 3 specifier string is specified, it is parsed and then converted to the Lab color space. See color for examples. If a color

d3.keys(object) Returns an array containing the property names of the specified object (an associative array). The order of the returned array is undefined.

d3.json(url[, callback]) Creates a request for the JSON file at the specified url with the default mime type application/json. This convenience constructor is approximately equivalent to: d3.request(url) .mimeType("application/json") .response(function(xhr) { return JSON.parse(xhr.responseText); }) .get(callback);

d3.isoParse The full ISO 8601 UTC time parser. Where available, this method will use the Date constructor to parse strings. If you depend on strict validation of the input format according to ISO 8601, you should construct a UTC parser function: var strictIsoParse = d3.utcParse("%Y-%m-%dT%H:%M:%S.%LZ");

d3.isoFormat The full ISO 8601 UTC time formatter. Where available, this method will use Date.toISOString to format.

d3.interval(callback[, delay[, time]]) Like timer, except the callback is invoked only every delay milliseconds; if delay is not specified, this is equivalent to timer. A suitable replacement for setInterval that is guaranteed to not run in the background. The callback is passed the elapsed time.