Logarithmic axis scale in Kendo Chart

Question

I have a scenario in which I need the a axis scale to be displayed in Logarithmic order. I did a little search and found that this option is not available but the posts are almost a year old. Has this functionality been provided in the latest releases?

Here are the links of Kendo forum that I looked into

http://www.kendoui.com/forums/dataviz/chart/logarithmic-scale.aspx http://www.kendoui.com/forums/dataviz/chart/does-kendo-support-log-scale.aspx

Answer 1

I know this is an old post, but i found it trying to do something like this. I found a workaround, and it may be it help somebody.

I found a way to implement a logarithmic scale in Kendo UI. Basically, the idea is convert the values from its logarithmic form to a linear form, then bound the data with a KendoUI serie ("scattered line" in my case) and replace the labels from the Y axis using a template.

.YAxis(axis => axis
    .Numeric()
    .Title("BER (dB)")
    .Labels(l => l.Template("#= formatLog2('{0:0}', value) #"))
    .Reverse()
    .AxisCrossingValue(double.MaxValue)
.Tooltip(tooltip => tooltip
    .Visible(true)
    .Template("#= formatLog('{0:0.00000000000000}', value.y) #")

and the JavaScript function "formatLog2". (it is a scratch code, just to ilustrate the point):

function formatLog2(format, value) {

    if (value < 0) value = value * -1;

    value = Math.pow(10, value);

    return kendo.format(format, value);
}

and the DataSource transform:

using (IDatabase db = Database.Create())
using (DataTable dt = new DataTable())
{
    db.ExecuteQuery(dt, Query);

    List<UnavailabilityChartPoint> l = new List<UnavailabilityChartPoint>();

    foreach (DataRow r in dt.Rows)
    {
        l.Add(new UnavailabilityChartPoint(
        r.Field<DateTime>("Date"),
        Math.Log10(r.Field<double>("UnSignalMonthly"))
        ));
    }

    return Json(l);
}

the important parts are the linear to log and the log to linear transforms:

value = Math.pow(10, value);    
Math.Log10(r.Field<double>("UnSignalMonthly"))

Hope this helps somebody.