Programmatically set drawCircle on a per value basis on LineChart - mpandroidchart

Is there a way to toggle drawCircle on individual data points? From the documentation it appears you can only enable this at the dataset level. I'm trying to draw circles for the min/max of a dataset.
If there isn't a way to draw circles on individual data points another workaround I've tried implementing has been to create a second dataset and only plot the corresponding X index and min/max Y value; every other value is set small enough that it is not visible in the viewport. The only problem here is I can't seem to plot both datasets without overwriting the first dataset's background fill.

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Scale domain vs filter selection in vega-lite: automatic axis scaling

In Scale Domains docs of Vega-Lite it is noted:
An alternate way to construct this technique would be to filter out
the input data to the top (detail) view like so:
{
"vconcat": [{
"transform": [{"filter": {"selection": "brush"}}],
...
}]
}
Which is indeed almost the same (although filter method being much slower, as noted in the docs), except for one difference:
With filter-selection method (demo), the y-axis of the upper chart will be automatically zoomed in to the selected points. This is pretty neat, especially if you have large amount of points.
With scale-domain method (demo), the y-axis remains frozen as you move the selection around.
The question: is it possible to have the y-axis automatically zoom in to the selected points as you move the selection, with "scale domain" method (same as it does with filter-selection method)?
Why is the above difference important? Imagine a stock price that has been increasing on average by a total of $1 every day last year (but within a particular day it may have experinced any kind of volatile behaviour) and we're plotting it with line marks. If you plot the entire year, you see the whole picture. If you zoom in on a particular day without resetting your y-axis zoom, however, your intraday price plot will be just a flat line, or close to that.
// I've checked all scale-domain-related issues on vega-lite, on altair repo and SO and couldn't find anything related; I've also posted this question on vega-lite repo on GH, but was forwarded over to SO.
No. Unless otherwise specified, the y scale is determined from all of the data within the plot.
When you filter the data, the data in the plot changes, which causes the y axis to change. When you change the scale based on an x-selection without filtering the data, it does not change the data in the plot, and so the y scale remains constant.
If you want the y-scale to be determined automatically based on the data within the selection, the only option is to filter on that selection.

Optimal display for overlapping series in a line chart

In a context of a line chart displaying time data in regular intervals where multiple series might overlap what would be the optimal way to:
A) hint the user that the chart has overlapping series?
B) give the user the capability to visualize all those series? Like spanning the series somehow?
For overlapping series in a line chart, I would keep the traditional line chart but put a label at the end of the graph with a color legend. The legend and label will help the user get information quickly.
Another version of a line chart for overlapping series can be a line area chat.
If you are not stuck on only line charts, I would suggest a bar chart. Below are some examples that you can use.
Example 1:
Example 2:
Example 3:
There are couple ways to indicate that there are overlapping series on a chart. You can increase the marker radius of one of them. The number of legend elements tells you how many series there is, too. Finally, you can distribute series on a different yAxis, with different top and height properties. Also, in styled mode, when you hover on legend item, other series opacity changes.
API Reference:
http://api.highcharts.com/highcharts/plotOptions.line.marker.radius
Examples:
http://jsfiddle.net/whsgpdyw/ - changing marker radius
http://jsfiddle.net/fuq6j4sg/ - each series on a different yAxis

core plot stacked graph crossing top border

I'm trying to create a stacked graph using core plot.i have followed this tutorial.I have a UISlider on sliding i'm updating my graph.The issue i'm facing is my top value for y-axis is touching top border(As in the screen shot). As per my requirement in need to round off the highest value to next 10th value so that my graph doesn't touch the borders.On changing my slider value the x and y axis should also get refresh,i'm doing it by regenerating plot but it takes a lot of memory.Any idea how can i achieve these requirement ?
Don't recreate the whole graph every time the values change. Call -reloadData on the graph to refresh the plot data and set the xRange and yRange of the plot space to change the scale of the axes.

How can I get and set the position of a draggable legend in matplotlib

I'm trying to get and set the position of a draggable legend in matplotlib. My application consists of an interactive GUI, which has a redraw/plot function that should perform the follow steps:
save the position of the current legend.
clear the current axes and perform various plotting operations, which may or may add labels to their plots.
build a new draggable legend (ax.legend().draggable()) and restore the old position of the legend.
In between these steps the user is free to drag the legend around, and the goal is to persist the legend position when the plots are redrawn.
My first approach was to use oldpos = legend.get_bbox_to_anchor() and legend.set_bbox_to_anchor(oldpos) in steps 1 and 3. However this causes to move the legend completely off the visible area.
Note that I have to use ax.legend() and cannot use fig.legend(lines, labels), since step 2 is completely decoupled, i.e., I don't know anything about lines and labels in step 3. According to answers to the question How to position and align a matplotlib figure legend? there seems to be a difference between these two possibilities regarding axes or figure coordinates. Obviously my problem calls for figure coordinates, but I haven't fully understood how to convert the bbox to a "bbox in figure coordinates".
The even more severe problem I just realized is that apparently legend.get_bbox_to_anchor() always seems to return the same values irrespective of the drag position. So maybe the anchor can only be (ab-)used to manipulate the position of static legends? Is there another/proper way to save and restore the position of a draggable legend?
By looking at the implementation of Legend I found out that there is an undocumented property _loc, which exactly does what I want. My solution now looks astonishingly simple:
oldLegPos = ax.get_legend()._loc
# perform all plotting operations...
legend = ax.legend().draggable()
legend._loc = oldLegPos
It looks like _loc automatically stores figure coordinates, since I do not have to convert the coordinates in any way (eg. when the plotting operations completely change the axes ranges/coordinates).

How to zoom only a particular slice in pie chart (CorePlot ios) and not the entire piechart

How to zoom only a particular slice in pe chart (CorePlot iOS) and not the entire piechart on user interaction.
I know the following method gives the slice touched:
-(void)pieChart:(CPTPieChart *)plot sliceWasSelectedAtRecordIndex:(NSUInteger)index
but i want to zoom only that slice ?
You can "explode" the selected slice. Implement the -radialOffsetForPieChart:recordIndex: method in your datasource and return a positive offset for the selected slice to make it pop out from the rest of the pie.
You can use the -sliceFillForPieChart:recordIndex: datasource method to control the fill for each slice. This would allow you to adjust the color and/or transparency to highlight the selected slice.
If you want to make the selected slice larger than the others, use a second pie chart to display the selected slice. Use the same plot data for both plots. On the first one, use the normal slice fill for all but the selected slice, which could be transparent. Reverse that pattern for the second plot, i.e., all slices transparent except the selected one.
You said like below...
If you want to make the selected slice larger than the others, use a second pie chart to display the selected slice. Use the same plot data for both plots.
I need like this concept.I am selecting one slice from outer pie chart and need to load that selected slice value in second pie chart, and make some effects. How to load that value in second chart.Sample code is very handful.