Often when I am learning new machine learning methods or experimenting with a data analysis algorithm I need to generate a series of 2D points. Teachers also do this often when making a lesson or tutorial.
In some cases I just create a function, add some noise, and plot it, but there are many times when I wish I could just click my mouse on a graph to generate points. For instance, when I want to generate a fairly complex relationship between x and y, it's a hassle to think of the right formulation to generate the points programmatically.
Does there exist a tool that will allow me to generate data points using my mouse, with an option to export to CSV (or other simple format)?
For example, I am currently learning how to use mutual information and entropy as a metric of dependence between variables. I'd like to see what happens when I have data that is clearly dependent but does not have a linear relationship, so I drew this image:
Now I just need a way to export the coordinates of the points to CSV. I realize this is a simple program and I could write my own, but surely someone has already done this and created a tool to do so? It could be a website, an .exe, Python source, or any other application.