Polar Plot in Grasshopper


Before I attempt to figure it out on my own with limited experience, I want to know if it is possible to create a polar plot using Grasshopper. The data is at a 30 locations…

I would like to figure out how do plot something like this:

(Source: JMSE | Free Full-Text | Experimental and Numerical Study of Pre-Swirl Stators PSS | HTML)

If only possible to only do a color contour polar plot, I would still be interested in learning how do to this.

Thank you in advance.

In principle, yes it’s possible. Because the plot consists of curves, text objects, and coloured regions, and those are all possible to make with Grasshopper. For those colours you’ll need to create a mesh with per-vertex colours, as creating (and displaying) bitmaps is not possible, at least without some plug-in.

As for things like iso-curves (your picture on the right), it’s almost the exact same approach. You create a flat, ring-shaped mesh, but instead of assigning colours to the vertices, you instead assign a z-coordinate. You now have a 3d mesh whose elevation equals the value. You must then contour or slice this mesh at appropriate elevations and project the resulting intersection curves back onto the plane.

The hardest part in all this may be the parsing of your original data. How is it formatted?

Hi David,

The original data is formatted in excel and each data point is linked to points which are labeled 1-180 which are given x, y, z coordinates (really only the y and z are needed since the x is constant).

As for the plot on the left hand side the points are based on the x, y, z coordinates which are assigned in array function such as polar array offset based on a diameter such like these points (5 circles * 36 points each) :

These points then have a fraction 0-1.0. A pressure assigned as well as a u,v, w.

add a file with data if you want an example of how to make a plot.