text: import "../math/number";
  import "ascending";
  import "quantile";
  
  d3.median = function (array, f) {
  	var numbers = [],
  		n = array.length,
  		a,
  		i = -1;
  	if(arguments.length === 1){
  		while(++i < n) if(d3_numeric(a = d3_number(array[i]))) numbers.push(a);
  	}else{
  		while(++i < n) if(d3_numeric(a = d3_number(f.call(array, array[i], i)))) numbers.push(a);
  	}
  	if (numbers.length) return d3.quantile(numbers.sort(d3_ascending), .5);
  };