Dynamic timeseries C3js chart

问题:

I am new to C3.js and trying to create a dynamic timeseries chart, please run the code in fiddle http://jsfiddle.net/roytirthadeep/54v7r0ab/

var chart = c3.generate({
        data: { 
            x: 'x',
            xFormat: '%Y-%m-%dT%H:%M:%S',
            columns: []
        },
         axis: {
            x: {
                type: 'timeseries',
                tick: {
                    format: '%H:%M:%S',
                }
            }
        },
        legend: {
            position: 'right'
        }
    });

    //"2013-01-01T00:00:01"
    var timeInc = 1;
    var value = 1;
    var interval = setInterval(function () {
        value = value + 1;
        timeInc++;
        var str;
        if (timeInc > 59) {
            clearInterval(interval);
            return;
        }
        if (timeInc >= 10) {
            str = ''+timeInc;
        } else {
            str = '0'+timeInc;
        }    
        xValue = "2013-01-01T00:00:"+str;
        if (value)
        if (value < 7) {
         console.log("xValue",xValue);
        console.log("value",value);
          chart.flow({
              columns: [
                ['x', xValue],
                ['data3', value]
              ],
              length:0
          });
        } else {
            chart.flow({
              columns: [
                ['x', xValue],
                ['data3', value],
                ['data4', value*2],
                ['data5', value/2],
                ['data6', value-1]  
              ],
              length:0
          });
        }    
    }, 1000);

Q1. Is this the right way to achieve the desired behaivor in C3.js ?

Q2. How to achieve this http://www.highcharts.com/stock/demo/dynamic-update behaivor of highcharts (starting from a blank chart)

I got a solution and added it as an answer.

回答1:

There is C3's flow api which does what you ask with less code, but annoyingly (especially after I wrote most of this answer) it has a bug where it doesn't remove points if the tab is hidden - https://github.com/c3js/c3/issues/1097

var chart = c3.generate({
    data: {
        x: 'x',
        columns: [
            ['x', '2012-12-28', '2012-12-29', '2012-12-30', '2012-12-31'],
            ['data1', 100, 230, 300, 330],
            ['data2', 250, 190, 230, 200],
            ['data3', 120, 90, 130, 180],
        ]
    },
    axis: {
        x: {
            type: 'timeseries',
            tick: {
                format: '%m/%d',
            }
        }
    }
});

var date = new Date ("2013-01-01");
setInterval(function () {
    chart.flow({
        columns: [
            ['x', new Date (date)],
            ['data1', 200 + (Math.random() * 300)],
            ['data2', 200 + (Math.random() * 300)],
            ['data3', 200 + (Math.random() * 300)],
        ],
        duration: 750,
    });
    date.setDate(date.getDate() + 1);
}, 2000);

http://jsfiddle.net/54v7r0ab/7/

Until that bug's fixed, I'd go with your answer as it doesn't exhibit the same problem.

---

EDIT: Possible fix. When using the flow api's done function, new data stops getting added to hidden tabs which avoids the 'pile-up' issue. However this is only useful if you don't want data constantly added when you're not looking :-), it wouldn't be a solution for a real-time graph.

http://jsfiddle.net/54v7r0ab/10/

var date = new Date ("2013-01-01");
var pushNew = function () {
    chart.flow({
        columns: [
            ['x', new Date (date)],
            ['data1', 200 + (Math.random() * 300)],
            ['data2', 200 + (Math.random() * 300)],
            ['data3', 200 + (Math.random() * 300)],
        ],
        duration: 750,
        done: function () {
          date.setDate(date.getDate() + 1);
          window.setTimeout (pushNew, 1);
      }
    });
}
pushNew();

回答2:

I got a solution to achieve the desired behavior like Highcharts, by resetting the x axis ranges and checking for threshold value. This might be helpful to others http://jsfiddle.net/54v7r0ab/5/

var chart = c3.generate({
    data: { 
        x: 'x',
        columns: []
    },
     axis: {
        x: {
            type: 'timeseries',
            tick: {
                format: '%H:%M:%S',
            }
        }
    },
    legend: {
        position: 'right'
    }
});
var chartObj = {
   "chart": chart,
   "redrawArgs": {},
   "truncThreshold": undefined
}

//"2013-01-01T00:00:01"
var date = 1463017666000;
var timeInc = 1000;
var value = 1;
var interval = setInterval(function () {
        var dataCols = [];
    date = date + timeInc;
    var minX = date - 10000;
    var maxX = date;
    var redrawArgs = chartObj.redrawArgs;
    if (!chartObj.truncThreshold) {
        chartObj.truncThreshold = maxX;
    } else if (minX > chartObj.truncThreshold) {
        redrawArgs.length = 1;
    } else {
        redrawArgs.length = 0;
    }
    chartObj.chart.axis.range({max: {x: maxX}, min: {x: minX}});
    value++;
    redrawArgs.duration = 0;
    if (value < 7) {
      dataCols.push(['x', date]);
      dataCols.push(['data 1', value]);
      redrawArgs.columns = dataCols;      
    } else {
        dataCols.push(['x', date]);
      dataCols.push(['data 1', value]);
      dataCols.push(['data 2', value*Math.random()])
      dataCols.push(['data 3', value/Math.random()]);
      dataCols.push(['data 4', value+Math.random()]);
      redrawArgs.columns = dataCols;
    }
    chartObj.chart.flow(redrawArgs);
}, 1000);