Here’s an image that came out of something I was working on this morning. I thought it might make an interesting border somewhere. The blue line is sin(x), the green line 0.7 sin(φ x), and the red line is their…

Here’s an image that came out of something I was working on this morning. I thought it might make an interesting border somewhere. The blue line is sin(x), the green line 0.7 sin(φ x), and the red line is their…

Tim Hopper asked on Twitter today: #rstats programming without @hadleywickham’s libraries is like ________ without _________. Some of the replies were: (skydiving, a parachute) (gouging your own eyes out, NULL) (dentistry, anesthesia) (shaving, a razor) (internet shopping, credit card) Clearly…

Michael J. Hammel is the author of The Artist’s Guide to GIMP, a book I reviewed three weeks ago. The following interview is based on my correspondence with Michael.

Learning how to edit images has been on my to-do list for a long time. I do some very basic editing with Paint.NET, but I keep meaning to learn to use GIMP. I heard years ago that GIMP is terribly…

When I first started using Inkscape, I read Inkscape: Guide to a Vector Drawing Program by Tavmjong Bah, 3rd edition. It’s now in its 4th edition, which I have not seen. I received a copy of The Book of Inkscape…

I appreciate spare design, but the new Windows logo is just boring. Here’s the rationale for the new logo according to The Windows Blog: But if you look back to the origins of the logo you see that it really…

Rod Carvalho wrote a post this morning announcing a beautiful 2010 calendar created by Ron Doerfler. Doerfler’s blog is entitled Dead Reckonings: Lost Art in the Mathematical Sciences. The calendar is an example of such lost art. It is illustrated…

My previous post described how to include an Inkscape drawing in a LaTeX document. This post describes how to use LaTeX in an Inkscape drawing, which is probably more useful. The LaTeX output is included not as bitmap but as…

The Inkscape drawing package can export to a large variety of vector drawing formats, including LaTeX. If you save your drawing to a file foo.tex, you can include the file in a LaTeX document as follows. \documentclass{article} \usepackage{pstricks} \begin{document} Testing…

Why would you want to plot a mathematical function using a drawing package like Inkscape rather than a mathematical package like Mathematica or R? One reason is that you may want plot for its visual properties. For example, you might…

Bézier curves are very common in computer graphics. They also interesting mathematical properties. This post will give a quick introduction to Bézier curves, describing them first in visual terms and then in mathematical terms. There are different degrees of Bézier…

Are squares A and B are the same color? I found this illusion on John Baez’s site. It was created by Edward Adelson in 1995 and is the subject of a Wikipedia article. Related post: Optical illusion, mathematical illusion

My previous post gave three algorithms for converting color to grayscale. This post gives more examples and details. The image below is a screenshot from an Excel spreadsheet illustrating color values and how the convert to grayscale. The R, G,…

How do you convert a color image to grayscale? If each color pixel is described by a triple (R, G, B) of intensities for red, green, and blue, how do you map that to a single number giving a grayscale…

Here’s today’s image from The Retro Press, a back-to-school ad from the September 9, 1957 issue of LIFE. The Retro Press blog highlights advertisements from the Gallery of Graphic Design.

Posted in Graphics