Getting Started Example anomaly

Not sure if this is the correct place to post this.

In the Getting Started document (http://nodebox.net/node/documentation/tutorial/getting-started.html) immediately after adding the Colorize node, there is a change in the ellipse pattern: The Shape node is set to 4:30-60, so there should be 4 ellipses in increasing radius from 30 - 60; yet there is now a 5th ellipse with a radius of 30 prior to the cycle repeating (two radius 30 ellipses in a row.) This same anomaly is seen when the polygon is added. I get the same result when I follow the example.

Where is this 5th element of the Shape node coming from?

Thanks!

It is because of list matching. There are 5 colors and four ellipses, so the list matching will assign an ellipse for every color, for the fifth color there is no ellipse anymore so it will take the first one again to match the five colours. Then it will start over again until the third list (= the number of grid points) is matched. Just create four colours and you will see the difference.

The page how NodeBox works explains list matching.

Thanks for the excellent responses! Node programming is new to me, and I can see it is going to take a little getting used to.