Question

我在使用d3js和日期方面遇到了一些麻烦：

这是一些数据，一个具有权重和日期的对象数组

var weights = [{"atdate":"2013-09-07","weight":"82","comment":"Reprise !"},
{"atdate":"2013-09-10","weight":"81.3","comment":""},
{"atdate":"2013-09-15","weight":"80.8","comment":""},
{"atdate":"2013-09-16","weight":"80.8","comment":""},
{"atdate":"2013-09-17","weight":"80.3","comment":""},
{"atdate":"2013-09-18","weight":"81.2","comment":""},
{"atdate":"2013-09-19","weight":"80.9","comment":""},
{"atdate":"2013-09-20","weight":"80.7","comment":""},
{"atdate":"2013-09-21","weight":"81","comment":""},
{"atdate":"2013-09-22","weight":"80.8","comment":""}];

您可以看到最短日期是2013-09-07，最长日期是2013-09-22

现在，我将此数据发送到函数

function draw_spline (_weights) {

    var parse_date = d3.time.format('%Y-%m-%d').parse;
    var weights = _weights.map(function(w) {
        w.atdate = parse_date(w.atdate);
        w.weight = parseFloat(w.weight);
        return w;
    })

    var x = d3.time.scale().range([0,width]);

    var boundaries_dates = d3.extent(weights, function(d){return d.atdate});
    console.log('boundaries_dates',boundaries_dates);
    x.domain(boundaries_dates);
    console.log('domain extent',x.domain());

    ...

我使用parse_date构造实际日期对象。这是控制台的输出：

boundaries_dates, Array [
    Mon Sep 23 2013 00:00:00 GMT+0200 , 
    Sun Sep 22 2013 00:00:00 GMT+0200 ]
domain extent, Array [
    Sat Sep 07 2013 00:00:00 GMT+0200 , 
    Sun Sep 22 2013 00:00:00 GMT+0200 ]

正如你所看到的那样，程度是错误的，而不是今天的2013-09-07。我想有最短的约会。

如果我将扩展区发送到扩展域，则scale.domain（）会返回我想要的值。（所以有办法得到我想要的东西，但感觉不对。）

所以，

如何使用d3.extent（）获得正确的范围？

如何从不包含它的数组中获得正确的第一个日期的比例？

谢谢

了解d3.js的范围

0 个答案: