the rose

Wedge length is a count in that direction. There is no left-to-right, so there is no trend.

What it leaves outArea grows faster than length, so a wedge twice as long looks four times as big. The eye reads the area.

2 · intermediate · polar · rung 2 · what’s reported

shipped on the platform · WindRose · rose

Two worked examples

Seven days, bent into a circle. Is there a trend?

Before you lookWrite down whether you expect earthquakes to prefer a day of the week.

civicweekday_nyc_rat_complaints.csv · 7 rows · 2 columns

rat complaints by day of the week, bent into a circle

What to look atWedge length is the count for that day. There is no left-to-right, so there is no trend — only which directions are long.

This example draws itself with a small script. With scripting off you can still read every word on this page, and the file itself is at data/weekday_nyc_rat_complaints.csv.

earth and spaceweekday_socal_quakes.csv · 7 rows · 2 columns

earthquakes by day of the week, bent into a circle

What to look atSeven wedges of almost equal length. A rose of nothing looks like a flower, which is the trap.

This example draws itself with a small script. With scripting off you can still read every word on this page, and the file itself is at data/weekday_socal_quakes.csv.

the pool

Now build one yourself.

The pool opens with this file and this shape already drawn, so your first move is to change something rather than to start from nothing. Bring your own CSV if you have one. Nothing is uploaded anywhere — the chart is drawn in your browser, your work saves there, and it downloads as a picture or as a project file you can open again.

Open the pool → the rose · weekday_nyc_rat_complaints.csv