【发布时间】：2020-10-06 12:18:15
【问题描述】：
我的值是我在时间序列中呈现的总分钟数。虽然分钟用于绘图，但我想更改轴刻度标签以显示此数据最接近的小时数。我解决这个问题的方法是添加一个.tickFormat()，将分钟转换为小时，然后返回d3.timeFormat()，小时格式和一个新日期设置为0，设置小时。虽然轴刻度标签很接近，但它们不正确。似乎有轻微的偏移、值的重复和比例不是从 0 开始（从 12 开始）。我应该使用不同的函数调用来更正比例吗？
这是有问题的代码：
svg.append("g")
.call(d3.axisLeft()
.scale(y)
.tickFormat((d, i) => {
var hours = Math.floor(d / 60);
console.log(hours)
console.log(new Date(0).setMinutes(hours))
return d3.timeFormat("%I")( new Date(0).setHours(hours))
}));
<meta charset="utf-8">
<!-- Load d3.js -->
<script src="https://d3js.org/d3.v4.js"></script>
<!-- Create a div where the graph will take place -->
<div id="my_dataviz"></div>
<style>
div.tooltip {
position: absolute;
text-align: center;
width: 100px;
height: 30px;
padding: 2px;
font: 12px sans-serif;
background: lightsteelblue;
border: 0px;
border-radius: 8px;
pointer-events: none;
}
</style>
<script>
var data = [
{ "x": "2020-04-26", "y": 461.0, "label": "7:41" },
{ "x": "2020-04-27", "y": 421.0, "label": "7:01" },
{ "x": "2020-04-28", "y": 519.0, "label": "8:39" },
{ "x": "2020-04-29", "y": 502.0, "label": "8:22" },
{ "x": "2020-04-30", "y": 511.0, "label": "8:31" },
{ "x": "2020-05-01", "y": 513.0, "label": "8:33" },
{ "x": "2020-05-02", "y": 496.0, "label": "8:16" },
{ "x": "2020-05-03", "y": 480.0, "label": "8:00" },
{ "x": "2020-05-04", "y": 364.0, "label": "6:04" },
{ "x": "2020-05-05", "y": 498.0, "label": "8:18" },
{ "x": "2020-05-06", "y": 467.0, "label": "7:47" },
{ "x": "2020-05-07", "y": 477.0, "label": "7:57" },
{ "x": "2020-05-08", "y": 431.0, "label": "7:11" },
{ "x": "2020-05-09", "y": 419.0, "label": "6:59" },
{ "x": "2020-05-10", "y": 471.0, "label": "7:51" },
{ "x": "2020-05-11", "y": 391.0, "label": "6:31" },
{ "x": "2020-05-12", "y": 481.0, "label": "8:01" },
{ "x": "2020-05-13", "y": 494.0, "label": "8:14" },
{ "x": "2020-05-14", "y": 506.0, "label": "8:26" },
{ "x": "2020-05-15", "y": 464.0, "label": "7:44" },
{ "x": "2020-05-16", "y": 474.0, "label": "7:54" },
{ "x": "2020-05-17", "y": 383.0, "label": "6:23" },
{ "x": "2020-05-18", "y": 385.0, "label": "6:25" },
{ "x": "2020-05-19", "y": 470.0, "label": "7:50" },
{ "x": "2020-05-20", "y": 465.0, "label": "7:45" },
{ "x": "2020-05-21", "y": 574.0, "label": "9:34" },
{ "x": "2020-05-22", "y": 473.0, "label": "7:53" },
{ "x": "2020-05-23", "y": 431.0, "label": "7:11" },
{ "x": "2020-05-24", "y": 497.0, "label": "8:17" },
{ "x": "2020-05-26", "y": 482.0, "label": "8:02" },
{ "x": "2020-05-27", "y": 492.0, "label": "8:12" },
{ "x": "2020-05-28", "y": 494.0, "label": "8:14" },
{ "x": "2020-05-29", "y": 469.0, "label": "7:49" },
{ "x": "2020-05-30", "y": 395.0, "label": "6:35" },
{ "x": "2020-05-31", "y": 427.0, "label": "7:07" },
{ "x": "2020-06-01", "y": 346.0, "label": "5:46" },
{ "x": "2020-06-02", "y": 416.0, "label": "6:56" },
{ "x": "2020-06-03", "y": 461.0, "label": "7:41" },
{ "x": "2020-06-04", "y": 486.0, "label": "8:06" },
{ "x": "2020-06-05", "y": 451.0, "label": "7:31" },
{ "x": "2020-06-06", "y": 533.0, "label": "8:53" },
{ "x": "2020-06-08", "y": 462.0, "label": "7:42" },
{ "x": "2020-06-09", "y": 461.0, "label": "7:41" },
{ "x": "2020-06-10", "y": 477.0, "label": "7:57" },
{ "x": "2020-06-11", "y": 458.0, "label": "7:38" },
{ "x": "2020-06-12", "y": 484.0, "label": "8:04" },
{ "x": "2020-06-13", "y": 389.0, "label": "6:29" },
{ "x": "2020-06-15", "y": 472.0, "label": "7:52" },
{ "x": "2020-06-16", "y": 462.0, "label": "7:42" },
{ "x": "2020-06-17", "y": 486.0, "label": "8:06" },
{ "x": "2020-06-18", "y": 489.0, "label": "8:09" },
{ "x": "2020-06-19", "y": 483.0, "label": "8:03" },
{ "x": "2020-06-20", "y": 426.0, "label": "7:06" },
{ "x": "2020-06-21", "y": 453.0, "label": "7:33" },
{ "x": "2020-06-22", "y": 489.0, "label": "8:09" },
{ "x": "2020-06-23", "y": 467.0, "label": "7:47" },
{ "x": "2020-06-24", "y": 474.0, "label": "7:54" },
{ "x": "2020-06-25", "y": 451.0, "label": "7:31" },
{ "x": "2020-06-26", "y": 450.0, "label": "7:30" },
{ "x": "2020-06-27", "y": 470.0, "label": "7:50" },
{ "x": "2020-06-29", "y": 247.0, "label": "4:07" },
{ "x": "2020-06-30", "y": 502.0, "label": "8:22" },
{ "x": "2020-07-01", "y": 464.0, "label": "7:44" }
]
// D3 date parser
for (var i=0; i < data.length; i++){
var parser = d3.timeParse("%Y-%m-%d")
data[i].date = parser(data[i].x);
}
var margin = { top: 10, right: 30, bottom: 30, left: 60 }
var width = 800 - margin.left - margin.right;
var height = 800 - margin.top - margin.bottom;
// Define the div for the tooltip
var div = d3.select("body").append("div")
.attr("class", "tooltip")
.style("opacity", 0);
var svg = d3.select("#my_dataviz")
.append("svg")
.attr( 'preserveAspectRatio',"xMinYMin meet")
.attr("viewBox", "0 0 " + (width + margin.left + margin.right) + " " + (height + margin.top + margin.bottom))
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")"); // translate(margin left, margin top)
var x = d3.scaleTime()
.domain([d3.min(data, function(d) { return d.date }), d3.max(data, function(d) { return d.date })])
.range([0, width]);
svg.append("g")
.attr("transform", "translate(" + 0 + "," + height + ")")
.call(d3.axisBottom(x));
// text label for the x axis
svg.append("text")
.attr("transform",
"translate(" + (width/2) + " ," + (height + margin.top + 20) + ")")
.style("text-anchor", "middle")
.text("Date");
var y = d3.scaleLinear()
.domain([0, d3.max(data, function(d){ return +d.y })])
.range([height, 0]);
svg.append("g")
.call(d3.axisLeft()
.scale(y)
.tickFormat((d, i) => {
var hours = Math.floor(d / 60);
console.log(hours)
console.log(new Date(0).setMinutes(hours))
return d3.timeFormat("%I")( new Date(0).setHours(hours))
}));
// text label for the y axis
svg.append("text")
.attr("transform", "rotate(-90)")
.attr("y", 0 - margin.left)
.attr("x",0 - (height / 2))
.attr("dy", "1em")
.style("text-anchor", "middle")
.text("Time Asleep (Minutes)");
// Add line path
svg.append("path")
.datum(data)
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-width", 1.5)
.attr("d", d3.line()
.x(function(d) { return x(d.date) })
.y(function(d) { return y(d.y) })
);
// Add the scatterplot (data points)
svg.selectAll("dot")
.data(data)
.enter().append("circle")
.attr("r", 3)
// Add tooltip on hover
.on("mouseover", function(d) {
div.transition()
.duration(200)
.style("opacity", .9);
div.html(d.x + "<br/>" + d.label)
.style("left", (d3.event.pageX) + "px")
.style("top", (d3.event.pageY - 30) + "px")
})
// Remove tooltip after hover
.on("mouseout", function(d) {
div.transition()
.duration(500)
.style("opacity", 0);
})
.transition()
.delay(function(d,i){ return (i*3)})
.duration(2000)
.attr("cx", function(d){ return x(d.date) })
.attr("cy", function(d){ return y(d.y) });
</script>【问题讨论】：
标签： d3.js