Is it possible using IGChartView to somehow retrieve the data points that make up the automatically generated trendline?
In my scenario, I want to show a custom marker/annotation at the beginning of the generated trendline. But since I don't know what the data points of the trendline are, I end up having to generate my trendline points programmatically and just display a spline line. Then I can display a custom marker, for example, on the second data point of the line, and no markers anywhere else. Basically it's an identifier of the line that displays on the line itself.
Any ideas would be helpful. Thanks.
Hello Jeff,
Thank you for contacting Infragistics.
After researching this it seems that the way you have been doing this is the best way to implement this. Even if you get the trendline datapoints you would still need a series in order to add the custom markers. So you will have to add the trendline as a series and then to add the custom marker.
Please let me know if you have any additional questions.
Thanks for your response.
Maybe in the future some way could be added to access the trendline data somehow. Perhaps a viewForMarkerInSeriesTrendline, or some .trendlineMarker property in the existing viewForMarkerInSeries?
Hi Jeff,
Is your main goal to have a start (and possibly an end) marker on a trendline? Or would you potentially want to have some markers somewhere along the trendline, as well?There are a couple of reasons trendlines don't have markers. First of all, most trendlines will have a different number of points than their series. Linear trendlines will only have two points, moving average will typically match the number of points in the series, and a polynomial trendline will likely have more points to get a smooth curve. The number of points here depends on the trendline type. Markers in a series, on the other hand tend to represent the number of points in the underlying data source. It's kind of tricky to provide a set of meaningful markers on a trendline... unless it's just the start and end points. In any case, I'm not trying to discredit this as a valid feature request, just wanted to get some more info.
Thanks.
Yes, my main goal was to place a marker on the start/end/or possibly both ends of the trendline.
In my particular scenario, I generate a scatter series quadratic trendline, whose series shows up in the legend, so no trendline marker is necessary. Additionally, I have historical options that can append additional series and trendlines to the same chart. In those historical cases, I don't add those series' to the legend, use the same series color (w/ a lower alpha), but still want to identify the lines somehow. That's where the start/end markers come into play.
I am just checking about the progress of this issue. Let me know if you need my further assistance on this issue.
Thank you for using Infragistics Components.