Since everyone else here was putting up banners, I created a banner for my blog. The text and figure come from Chapter 8 (The Deltoid) of EH Lockwood's A Book of Curves (1961). It was on sale for $1 at a book sale, so I snapped it up.
A deltoid is the concave triangular curve formed when a small circle rolls around the inside of a circle three times as big. Eric Weisstein's Mathworld has a nice animation as well as a description of its properties.
If you've ever played with Spirograph you might have drawn a deltoid. Under the fold is a spirograph applet (courtesy of Anu Garg) that lets you create this curve and other pretty ones:
More like this
A deltoid is the concave triangular curve formed when a small circle rolls around the inside of a circle three times as big. Eric Weisstein's Mathworld has a nice animation as well as a description of its properties.
I use deltoids for the ends of the cartouches in the sidebar…
(This is a guest post written by Mo, the Neurophilosopher.)
I'm very pleased to announce that the fantastic Bioephemera has been "acquired" by ScienceBlogs. When I first started reading it, I knew that I had found a unique blog, and it soon became one of my favourites.
(More below the fold...)…
If you've been around Scienceblogs today, or on Twitter, you may have noticed that there appears to be a new blog around these parts.
On behalf of the team here at ScienceBlogs, I'd like to welcome you to Food Frontiers, a new project presented by PepsiCo. As part of this partnership, we'll hear…
Let's start with a pretty simple function. It's not this week's official Sunday Function, but we'll use it to get there.
Take the number 1, divide it by x. Pretty easy. Now imagine putting a dot at the point x = 1 on the x axis, and draw a line straight up from there to the curve formed by…
I always assumed that deltoid was a reference to the awe-inspiring shoulders you developed from years of power-lifting.... Next you'll be telling be that my subscription to Penthouse is not for the real estate listings!
The interesting thing is how a simple process can produce spikes. The entire economics profession is based on everything being non-spiky. In other words variables like tax and consumption are linked by smooth curves with no abrupt changes.
It's good to see the deltoid again - although I misss the lime green.