JavaScript Charts: Line chart with logarithmic value axis
<script type="text/javascript">
var chart;
var chartData = [{date: new Date(2012, 3, 1),
price: 20
}, {
date: new Date(2012, 3, 2),
price: 75
}, {
date: new Date(2012, 3, 3),
price: 15
}, {
date: new Date(2012, 3, 4),
price: 75
}, {
date: new Date(2012, 3, 5),
price: 158
}, {
date: new Date(2012, 3, 6),
price: 57
}, {
date: new Date(2012, 3, 7),
price: 107
}, {
date: new Date(2012, 3, 8),
price: 89
}, {
date: new Date(2012, 3, 9),
price: 75
}, {
date: new Date(2012, 3, 10),
price: 132
}, {
date: new Date(2012, 3, 11),
price: 158
}, {
date: new Date(2012, 3, 12),
price: 56
}, {
date: new Date(2012, 3, 13),
price: 169
}, {
date: new Date(2012, 3, 14),
price: 24
}, {
date: new Date(2012, 3, 15),
price: 147
}];
var average = 90.4;
AmCharts.ready(function () {
// SERIAL CHART
chart = new AmCharts.AmSerialChart();
chart.pathToImages = "/lib/samples/javascript/images/";
chart.panEventsEnabled = true;
chart.zoomOutButton = {
backgroundColor: "#000000",
backgroundAlpha: 0.15
};
chart.dataProvider = chartData;
chart.categoryField = "date";
// AXES
// category
var categoryAxis = chart.categoryAxis;
categoryAxis.parseDates = true; // as our data is date-based, we set parseDates to true
categoryAxis.minPeriod = "DD"; // our data is daily, so we set minPeriod to DD
categoryAxis.dashLength = 1;
categoryAxis.gridAlpha = 0.15;
categoryAxis.axisColor = "#DADADA";
categoryAxis.gridCount = 15;
categoryAxis.autoGridCount = false;
// we want custom date formatting, so we change it in next line
categoryAxis.dateFormats = [{
period: "DD",
format: "DD"
}, {
period: "WW",
format: "MMM DD"
}, {
period: "MM",
format: "MMM"
}, {
period: "YYYY",
format: "YYYY"
}];
// value
var valueAxis = new AmCharts.ValueAxis();
valueAxis.axisColor = "#DADADA";
valueAxis.dashLength = 1;
valueAxis.logarithmic = true; // this line makes axis logarithmic
chart.addValueAxis(valueAxis);
// GUIDE for average
var guide = new AmCharts.Guide();
guide.value = average;
guide.lineColor = "#CC0000";
guide.dashLength = 4;
guide.label = "average";
guide.inside = true;
guide.lineAlpha = 1;
valueAxis.addGuide(guide);
// GRAPH
var graph = new AmCharts.AmGraph();
graph.type = "smoothedLine";
graph.bullet = "round";
graph.bulletColor = "#FFFFFF";
graph.bulletBorderColor = "#00BBCC";
graph.bulletBorderThickness = 2;
graph.bulletSize = 7;
graph.title = "Price";
graph.valueField = "price";
graph.lineThickness = 2;
graph.lineColor = "#00BBCC";
chart.addGraph(graph);
// CURSOR
var chartCursor = new AmCharts.ChartCursor();
chartCursor.cursorPosition = "mouse";
chart.addChartCursor(chartCursor);
// SCROLLBAR
var chartScrollbar = new AmCharts.ChartScrollbar();
chart.addChartScrollbar(chartScrollbar);
// WRITE
chart.write("chartdiv");
});
</script>
<div id="chartdiv" style="width: 100%; height: 400px;"></div>
 Line chart with logarithmic value axis |
