Trying to combine two amcharts graphs, but getting “Data fields for series are not properly defined.” error

Question

I am trying to combine two graphs of amcharts into one including the slider. But I am getting the "Data fields for series are not properly defined." error.

Answer 1

Try adding series.yAxis = valueAxis; to your createSeries()

Adding this for future refs.

// Themes begin
am4core.useTheme(am4themes_animated);
// Themes end

var chart = am4core.create("chartdiv", am4charts.XYChart);

var data = [];
var price = 100;
var quantity = 1000;
for (var i = 0; i < 300; i++) {
    price += Math.round((Math.random() < 0.5 ? 1 : -1) * Math.random() * 100);
    quantity += Math.round((Math.random() < 0.5 ? 1 : -1) * Math.random() * 1000);
    data.push({ date: new Date(2000, 1, i), price: price, quantity: quantity });
}

var interfaceColors = new am4core.InterfaceColorSet();

chart.data = data;
// the following line makes value axes to be arranged vertically.
chart.leftAxesContainer.layout = "vertical";




// uncomment this line if you want to change order of axes
//chart.bottomAxesContainer.reverseOrder = true;

var dateAxis = chart.xAxes.push(new am4charts.DateAxis());
dateAxis.renderer.grid.template.location = 0;
dateAxis.renderer.ticks.template.length = 8;
dateAxis.renderer.ticks.template.strokeOpacity = 0.1;
//dateAxis.renderer.grid.template.disabled = true;
dateAxis.renderer.ticks.template.disabled = false;
dateAxis.renderer.ticks.template.strokeOpacity = 0.2;

chart.leftAxesContainer.pixelPerfect = true;
dateAxis.pixelPerfect = true;
dateAxis.renderer.pixelPerfect = true;
dateAxis.renderer.gridContainer.layout = "absolute";

// these two lines makes the axis to be initially zoomed-in
//dateAxis.start = 0.7;
//dateAxis.keepSelection = true;

var valueAxis = chart.yAxes.push(new am4charts.ValueAxis());
valueAxis.tooltip.disabled = true;
valueAxis.zIndex = 1;
valueAxis.renderer.baseGrid.disabled = true;
// height of axis
valueAxis.height = am4core.percent(60);
valueAxis.renderer.inside = true;
valueAxis.renderer.labels.template.verticalCenter = "bottom";
valueAxis.renderer.labels.template.padding(2,2,2,2);
//valueAxis.renderer.maxLabelPosition = 0.95;
valueAxis.renderer.fontSize = "0.8em"

// uncomment these lines to fill plot area of this axis with some color
valueAxis.renderer.gridContainer.background.fill = interfaceColors.getFor("alternativeBackground");
valueAxis.renderer.gridContainer.background.fillOpacity = 0.05;


var series = chart.series.push(new am4charts.LineSeries());
series.dataFields.dateX = "date";
series.dataFields.valueY = "price";
series.tooltipText = "{valueY.value}";
series.name = "Series 1";




var valueAxis2 = chart.yAxes.push(new am4charts.ValueAxis());
valueAxis2.tooltip.disabled = true;



// height of axis
valueAxis2.height = am4core.percent(40);
valueAxis2.zIndex = 3
// this makes gap between panels
valueAxis2.marginTop = 30;
valueAxis2.renderer.baseGrid.disabled = true;
valueAxis2.renderer.inside = true;
valueAxis2.renderer.labels.template.verticalCenter = "bottom";
valueAxis2.renderer.labels.template.padding(2,2,2,2);
//valueAxis2.renderer.maxLabelPosition = 0.95;
valueAxis2.renderer.fontSize = "0.8em"

// uncomment these lines to fill plot area of this axis with some color
valueAxis2.renderer.gridContainer.background.fill = interfaceColors.getFor("alternativeBackground");
valueAxis2.renderer.gridContainer.background.fillOpacity = 0.05;

var series2 = chart.series.push(new am4charts.ColumnSeries());
series2.columns.template.width = am4core.percent(50);
series2.dataFields.dateX = "date";
series2.dataFields.valueY = "quantity";
series2.yAxis = valueAxis2;
series2.tooltipText = "{valueY.value}";
series2.name = "Series 2";

chart.cursor = new am4charts.XYCursor();
chart.cursor.xAxis = dateAxis;

var scrollbarX = new am4charts.XYChartScrollbar();
scrollbarX.series.push(series);
scrollbarX.marginBottom = 20;
chart.scrollbarX = scrollbarX;

let rectangle = chart.plotContainer.createChild(am4core.Rectangle)
rectangle.fillOpacity = 1;
rectangle.width = am4core.percent(100);
rectangle.fill = am4core.color("#ffffff")
rectangle.isMeasured = false;
rectangle.height = 29;
rectangle.zIndex = 1000;

valueAxis2.events.on("positionchanged", function(){
  rectangle.y = valueAxis2.pixelY - rectangle.pixelHeight - 1;
})

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

#chartdiv {
  width: 100%;
  height: 600px;
}

Source :https://codepen.io/team/amcharts/pen/QYMREK