cestella

d3 scatterplot example using the Breakfast Cereal Dataset from http://idvbook.com and based on the scatterplot example at http://bl.ocks.org/mbostock/3887118

cestella

Here's a d3 plugin that allows you to create a polygon selection. You instantiate it just like d3.svg.brush.

var brush = d3.svg.polybrush();

It has an extra public method that 'brush' does not, and that's 'isWithinExtent(x, y)'. You can use this method to test if a given point falls within the drawn extent.

if (brush.isWithinExtent(x, y)) {
  console.log("I'm inside!");
}

cestella

• Click into the drawing area to start the selection frame
• move the mouse to resize the selection frame
• Release the mouse button to resize the selection frame

(The circles are just for illustrating purposes)