Move two reference lines in JFreechart - graph

I am using JFreechart - createLineChart and plotting some data. I want to set two thresholds; one upper and another lower. To represent the same I want to draw reference lines. User must be able to drag these lines to adjust the values for upper and lower thresholds. Is it possible to implement? Till now I could only draw the graph with dataset.I could even get the mouse click(x,y) coordinates in pixel. I have no clue how to add new lines to the graph and make them drag. Kindly help.

Along with CrosshairOverlay, I used multiple annotations. Following link helped me a lot! Thanks.
JFreeChart: Dynamic point selection in ChartPanel using ChartMouseListener and mouse move

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Tableau - Plotting multiple lines in one graph

I'm trying to plotting multiple lines in one single graph. I've combined two of them using dual axis, but I don't know how should I add another.
Thank you in advance for any help.
Since you have mentioned that you want to show multiple measures in one viz it means that one axis is sufficient for all these measures. Therefore, Instead of creating dual axis chart, do it like this-
Step-1 Build line chart with one measure.
Step-2 Drop another measure on the axis directly instead of rows/column shelf where you'll see a double bar icon like the screenshot.
step-3 Drop additional mesaures either in similar ways or onto measure values pane created automatically. See a demonstration screenshot below on sample superstore

How to set two identical y-scales in the same graph in Labview?

When a graph is very wide I want to show the y-axis values also on the right side of the graph so it becomes easier to read the corresponding values of the lines.
I know how to duplicate the left axis to the right. And when the graph is created I use ActYscl to set the range of scale nr 0 (left) to scale nr 1 (right). This works when the graph is created and also the zoom and pan function work on both y-scales. However, when I use the Autoscale function of the Graph Pallet, only the initial axis is scaled (probably because the graph data are only linked to the original axis).
Is there a way to make the autoscale function work for both y-axis at the same time?
Charts and graphs have an Autoscale Range Change event. Use an event structure to catch this event and update the range of the duplicate scale to match the first one:
I've used a chart for this example as it's simpler, but it should work the same for a graph. Of course you need a way of telling the event loop when to exit; I've used the Value Changed event of the stop button. If your application uses an event-driven structure anyway, you should just be able to add the autoscale event to your existing event loop.

Creating a grid on a map in R using grid points

I'm clearly struggling with this problem for a day now and can't seem to find a nice solution to it. I would really appreciate some help and I'm really a novice in R (since last week).
Problem 1:
I have a set CSV representing grid points which I can parse into a data frame (pointname, latitude, longitude).
Eg:
name,latitude,longitude
x0y0,35.9767,-122.605
x1y0,35.9767,-122.594
x2y0,35.9767,-122.583
x0y1,35.9857,-122.605
x1y1,35.9857,-122.594
x2y1,35.9857,-122.583
x0y2,35.9947,-122.605
x1y2,35.9947,-122.594
x2y2,35.9947,-122.583
The points in this file represent the lower left corner and are arranged in row major format, meaning lowest horizontal grid points first. Each point is a certain great circle distance away from its neighbors (1km). I want to create a grid overlay on a map which I've plotted using ggmap.
What I've tried or considered:
map.grid() - this is really not useful to me as I'm not looking for any kind of projection.
geom_vline() and geom_hline(). These look good but I don't have constant x and y intercepts on a plane. Moreover, once I create a grid, I'd like to use the grid to color against a density.
geom_rect() and geom_tile(). These look really promising and may be what I want. But I'm not able to find a good way of working with these.
I'd like to fill these grid boxes later with another parameter. Any suggestions on how I can create such a grid? This may be a trivial question but I don't know a lot of R yet.
Problem 2:
How can I store or hold such a grid so that I given a point (lat,lon), I can quickly get to that grid. In fact my whole back end is in C++ and can directly output the grid name x<n>y<n> directly against a given search point. I somehow am finding it difficult to count such points against grid points so that I can fill grid with a representative color.
I'm not sure if everything of what I'm saying is clear. Please tell me if I've to clarify something.
Also note that I've Googled quite a lot and not found relevant answers although some looked close.
Eg: This, ThisToo
Thanks for the help!

Tableau map shapes overlapped

I am trying to render some geographic data onto the map in Tableau. However, some data points located at the same point, so the shape images of the data points overlaps together. By clicking on a shape, you could only get the top one.
How can we distinguish the overlapped data points in Tableau? I know that we can manually exclude the top data to see another, but is there any other way, for example, make a drop down list in the right click menu to select the overlapped data points?
Thank you!
There are a couple of ways to deal with this issue.
Some choices you can try are:
Add some transparency to the marks by editing the color shelf properties. That way at least you get a visual indication when there are multiple marks stacked on top of each other. This approach can be considered a poor man's heat map if you have many points in different areas as the denser/darker sections will have more marks. (But that just affects the appearance and doesn't help you select and view details for marks that are covered by others)
Add some small pseudo-random jitter to each coordinate using calculated fields. This will be easier when Tableau supports a rand() function, but in the meantime you can get creative enough using other fields and the math function to add a little jitter. The goal here is to slightly shift locations enough that they don't stack exactly, but not enough to matter in precision. Depends on the scale.
Make a grid style heat map where the color indicates the number of data points in each grid. To do this, you'll need to create calculated fields to bin together nearby latitudes or longitudes. Say to round each latitude to a certain number of decimal places, or use the hex bin functions in Tableau. Those calculated fields will need to have a geographic role and be treated as continuous dimensions.
Define your visualization to display one mark for each unique location, and then use color or size to indicate the number of data points at that location, as opposed to a mark for each individual data point

Core Plot: Constrain axis only when it gets near the edge of the graph

I am using Core Plot in my iPad application to plot some data points on a scatter plot. I would like the axes to pan around with the data until one of the axes gets near the edge of the graph. Then I would like that axis to be constrained so that it does not go beyond the edge of the graph. I know that I can use CPTConstraints to fix the axes, but I don't want them to always be fixed. I simply want them to be fixed when they come near the edge of the graph so that they remain visible. I've attached some screenshots of my application to show you what I mean.
Use a plot space delegate to monitor changes to the plot space. Implement the -plotSpace:willChangePlotRangeTo:forCoordinate: delegate method and use the new plot range to decide whether to set the orthogonalCoordinate or constraints to position the axis.

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