从x轴过渡：条形图

Question

我需要从x轴过渡（从下到上）。但是现在我正在从上到下地过渡吧。我已经使用d3.js和Json对象。

JS代码如下：

var margin = {top: 20, right: 20, bottom: 30, left: 40}, 
    width = 600 - margin.left - margin.right, 
    height = 400 - margin.top - margin.bottom; 

var x = d3.scale.ordinal() 
    .rangeRoundBands([0, width], .6); 

var y = d3.scale.linear() 
    .range([height, 0]); 

var xAxis = d3.svg.axis() 
    .scale(x) 
    .orient("bottom"); 

var yAxis = d3.svg.axis() 
    .scale(y) 
    .orient("left") 
    .ticks(10); 

var svgBar = d3.select("body").append("svg") 
    .attr("width", width + margin.left + margin.right) 
    .attr("height", height + margin.top + margin.bottom) 
    .append("g") 
    .attr("transform", "translate(" + margin.left + "," + margin.top + ")"); 
d3.json("data.json", function(error, data) { 
    function type(d) { 
    d.Speed = +d.Speed; 
} 
    x.domain(data.map(function(d) { return d.Days; })); 
    y.domain([0, d3.max(data, function(d) { return d.Speed; })]); 
    svgBar.append("g") 
     .attr("class", "x axis") 
     .attr("transform", "translate(0," + height + ")") 
     .call(xAxis); 

    svgBar.append("g") 
     .attr("class", "y axis") 
     .call(yAxis) 
    .append("text") 
     .attr("transform", "rotate(-90)") 
     .attr("y", 6) 
     .attr("dy", ".71em") 
     .style("text-anchor", "end") 
     .text("Speed"); 

    var graphTransition = svgBar.selectAll("bar") 
     .data(data) 
     .enter().append("rect") 
     .attr("class", "bar") 
     .attr("x", function(d) { return x(d.Days); }) 
     .attr("width", x.rangeBand()) 
     .attr("y", function(d) { return y(d.Speed); }) 
     .attr("height",0);// Initial Height at loading 

    graphTransition 
    .transition() 
    .attr("height", function(d) { return height - y(d.Speed); }) //Bar height after transition 
    .duration(1000); 

}); 

JSON是如下：

[ 

    {"Days":"Mon","Speed":150}, 
    {"Days":"Tue","Speed":200} 

] 

有可能是我从我的最终错过了一个愚蠢的事情。任何帮助表示感谢，并提前致谢。

Answer 1

试试这个

var graphTransition = svgBar.selectAll("bar") 
    .data(data) 
    .enter().append("rect") 
    .attr("class", "bar") 
    .attr("x", function(d) { return x(d.Days); }) 
    .attr("width", x.rangeBand()) 
    .attr("y", function(d) { return height; }) 
    .attr("height",0); 

graphTransition 
.transition() 
.delay(100) 
.attr("height", function(d) { return height - y(d.Speed); }) 
.attr("y", function(d) { return y(d.Speed); }) 
.duration(1000);