Cleve’s Corner: Cleve Moler on Mathematics and Computing

Origins of Colormaps 2

Posted by Cleve Moler,

Steve Eddins has recently posted a series in his blog about colormaps. I want to add one more post. With release R2014b, we are retiring jet as the default colormap, after many years of faithful service. But did you ever wonder where jet originated, and how it came to be the default? And did you ever come across colormaps like pink and bone?... read more >>

The Three n Plus One Conjecture 2

Posted by Cleve Moler,

If $n$ is odd, replace $n$ by $3n+1$, if not, replace $n$ by $n/2$. Repeat. A famous conjecture made by Lothar Collatz is that no matter what value of $n$ is chosen to start, the process eventually terminates at $n=1$. Do not expect a proof, or a counterexample, in this blog.... read more >>

Prime Spiral 2

Posted by Cleve Moler,

The prime spiral was discovered by Stanislaw Ulam in 1963, and featured on the cover of Scientific American in March, 1964.... read more >>

Jahnke and Emde, Revisited 1

Posted by Cleve Moler,


An incredible book, published in several editions from 1909 to 1933, by German mathematicians Eugene Jahnke and Fritz Emde, contains definitions and formulas for mathematical functions, hand-calculated tables of function values, and meticulous hand-drawn 2- and 3-dimensional graphs. An English edition was published by Dover in 1945.... read more >>

These postings are the author's and don't necessarily represent the opinions of MathWorks.