D3 random time series

by jarandaf

CSS

svg {
  font: 10px sans-serif;
}

.axis path,
.axis line {
  fill: none;
  stroke: #000;
  shape-rendering: crispEdges;
}

.line {
  fill: none;
  stroke: steelblue;
  stroke-width: 1.5px;
}

JavaScript

var margin = {
    top: 20,
    left: 20,
    right: 20,
    bottom: 20
};

var width = 750 - margin.left - margin.right;
var height = 750 - margin.top - margin.bottom;

var randomDate = function (start, end) {
    return new Date(start.getTime() + Math.random()*(end.getTime() - start.getTime()));  
};

var data = d3.range(1000).map(function (d) {
    return {x: randomDate(new Date(2015, 0, 1), new Date(2015, 0, 20)), y: Math.random()*10};     
}).sort(function (a, b) {
    return a.x.getTime() - b.x.getTime();    
});

var svg = d3.select('body').append('svg')
    .attr('width', width + margin.left + margin.right)
    .attr('height', height +  margin.top + margin.bottom);

var g = svg.append('g')
    .attr('transform', 'translate(' + margin.left + ',' + margin.top + ')');

var x = d3.time.scale()
    .range([0, width]);
var xAxis = d3.svg.axis()
    .scale(x)
    .orient('bottom');

var y = d3.scale.linear()
    .range([height, 0]);
var yAxis = d3.svg.axis()
    .scale(y)
    .orient('left');

var line = d3.svg.line()
    .x(function (d) { return x(d.x); })
    .y(function (d) { return y(d.y); });

g.append('path')
    .attr('class', 'line')
    .attr('d', line(data));

g.append('g')
    .attr('class', 'x axis')
    .attr('transform', 'translate(0,' + height + ')')
    .call(xAxis);

g.append('g')
    .attr('class', 'y axis')
    .call(yAxis);

var tick = function () {
    var minMax = d3.extent(data, function (d) {
        return d.x; 
    });
    var duration = 250;
    // 1 day offset
    var offset = 24*60*60*1000;
    var from = minMax[0].getTime();
    // 2-days window
    var timeWindow = [from, from + 2*offset];
    
    // Recompute x,y domains
    x.domain(timeWindow);
    y.domain([0, d3.max(data, function (d) { return d.y; })]);
    
    // Redraw the line
    g.select('.line')
        .attr('d', line(data))
        .attr('transform', null);
    
    // Update x axis
    g.select('.x.axis')
        .transition()
        .duration(duration)
       ...