Parallel Coordinates Introduction

To create a parallel coordinate plot, you first lay out an axis for each variable of interest. In this demonstration, we have four variables we wish to explore.

Parallel Coords Axes.png

Each data point in a data set has a particular value for each of the four variables, creating an intersection point on each of the four axes. We connect those intersections with lines, creating a multi-axis representation of a single data point.

Parallel Coords One.png

So far, so good. Let's add another data point.

Parallel Coords Two.png

And more...

Parallel Coords Many.png

Interesting. We can start seeing trends in the data. Let's add all of the data points in the mesh.

Parallel Coords Ack.png

Ack! This method doesn't scale. We need a better representation.

VisIt can calculate a density of the lines, in essense a 2 dimensional histogram for each pair of axes, and directly plot that.

Parallel Coords Density.png

That's nice! We can see the trends of the data.

We can also turn on the Axis Restriction tool and limit the data.

Parallel Coords Selection.png

That's neat! We can see both the focus area we defined with the Axis Restriction tool and the context in which that data selection sits.