This week’s *That’s Maths* column in *The Irish Times* (TM058, or search for “thatsmaths” at irishtimes.com) is about George Boole, the first Professor of Mathematics at Queen’s College Cork.

## Posts Tagged 'Algorithms'

### The Year of George Boole

Published December 4, 2014 Irish Times ClosedTags: Algorithms, Computer Science, History, Logic

### Sunflowers and Fibonacci: Models of Efficiency

Published June 5, 2014 Irish Times ClosedTags: Algorithms, Applied Maths, biology, modelling

The article in this week’s *That’s Maths* column in *The Irish Times* ( TM046 ) is about the maths behind the efficient packing of sunflowers and many other plants

Strolling along Baggot Street in Dublin recently, I noticed a plaque at the entrance to the Ibec head office. It showed a circular pattern of dots, reminiscent of the head of a sunflower. According to the Ibec website, “The spiral motif brings dynamism … and hints at Ibec’s member-centric ethos.” Wonderful! In fact, the pattern in the logo is vastly more interesting than this. Continue reading ‘Sunflowers and Fibonacci: Models of Efficiency’

The term “Chaos Game” was coined by Michael Barnsley [1], who developed this ingenious technique for generating mathematical objects called fractals. We have discussed a particular fractal set on this blog: see Cantor’s Ternary Set.

The Chaos Game is a simple algorithm that identifies one point in the plane at each stage. The sets of points that ultimately emerge from the procedure are remarkable for their intricate structure. *The relationship between the algorithm and fractal sets is not at all obvious*, as there is no evident connection between them. This element of surprise is of one of the delights of mathematics.

### Speed Cubing & Group Theory

Published February 13, 2014 Irish Times ClosedTags: Algebra, Algorithms, Group Theory, Puzzles

The article in this week’s *That’s Maths* column in the* Irish Times* ( TM038 ) is about Rubik’s Cube and the Group Theory that underlies its solution.

### French Curves and Bézier Splines

Published February 6, 2014 Occasional ClosedTags: Algorithms, Computer Science, Numerical Analysis

A French curve is a template, normally plastic, used for manually drawing smooth curves. These simple drafting instruments provided innocent if puerile merriment to generations of engineering students, but they have now been rendered obsolete by computer aided design (CAD) packages, which enable us to construct complicated curves and surfaces using mathematical functions called Bézier splines.

### Pythagorean triples

Published January 23, 2014 Occasional ClosedTags: Algorithms, Geometry, History

The Pythagorean theorem states that the square of the hypotenuse of a right triangle is equal to the sum of the squares of the other two sides. It can be written as an equation,

*a ^{2 }+ b^{2} = c^{2},*

where *c* is the length of the hypotenuse, and *a* and *b* are the lengths of the other two sides.

### The Simpler the Better

Published October 3, 2013 Irish Times ClosedTags: Algorithms, Applied Maths, Computer Science

This week’s* That’s Maths* in *The Irish Times* ( TM030 ) is about Linear Programming (LP) and about how it saves millions of Euros every day through optimising efficiency.

A Berkeley graduate student, George Dantzig, was late for class. He scribbled down two problems written on the blackboard and handed in solutions a few days later. But the problems on the board were not homework assignments; they were two famous unsolved problems in statistics. The solutions earned Dantzig his Ph.D.

Continue reading ‘The Simpler the Better’

### The Ups and Downs of Hailstone Numbers

Published July 11, 2013 Occasional ClosedTags: Algorithms, Arithmetic, Number Theory

Hailstones, in the process of formation, make repeated excursions up and down within a cumulonimbus cloud until finally they fall to the ground. We look at sequences of numbers that oscillate in a similarly erratic manner until they finally reach the value 1. They are called** hailstone numbers**.

Continue reading ‘The Ups and Downs of Hailstone Numbers’

### CT Scans and the Radon Transform

Published March 7, 2013 Irish Times ClosedTags: Algorithms, medicine

Last December, Dublin’s Tallaght Hosptal acquired a new CT scanner, a Toshiba Aquilon Prime, the first of its type in the country. The state-of-the-art scanner is housed in a room with a ‘sky ceiling’ that allows patients to enjoy an attractive outdoor image during the scanning process.

This equipment, which cost €600,000 will undoubtedly result in timely treatment of patients and the saving of lives. The process of generating images from CT scans is described in the latest *That’s Maths* column (TM016) in the Irish Times.

### Singularly Valuable SVD

Published February 14, 2013 Occasional ClosedTags: Algebra, Algorithms, Computer Science, Numerical Analysis

In many fields of mathematics there is a result of central importance, called the “Fundamental Theorem” of that field. Thus, the fundamental theorem of arithmetic is the unique prime factorization theorem, stating that any integer greater than 1 is either prime itself or is the product of prime numbers, unique apart from their order.

The fundamental theorem of algebra states that every non-constant polynomial has at least one (complex) root. And the fundamental theorem of calculus shows that integration and differentiation are inverse operations, uniting differential and integral calculus.

**The Fundamental Theorem of Linear Algebra**

Continue reading ‘Singularly Valuable SVD’

Will computers ever be able to do mathematical research? Automatic computers have amazing power to analyze huge data bases and carry out extensive searches far beyond human capabilities. They can assist mathematicians in checking cases and evaluating functions at lightning speed, and they have been essential in producing proofs that depend on exhaustive searches.

The* That’s Maths* column in this week’s *Irish Times* ( TM014 ) is about the use of computers for proving mathematical theorems, and also for simulating physical systems. Continue reading ‘Computer Maths’

This week’s *That’s Maths* column ( TM011 ) discusses the challenge faced by Santa Claus: he has about a billion homes to visit in one night, so he needs to be smart in picking his route. The challenge he faces is called the *Travelling Salesman Problem,* or TSP. Continue reading ‘Santa’s TSP Algorithm’

### Carving up the Globe

Published October 18, 2012 Irish Times ClosedTags: Algorithms, Geometry, Numerical Analysis, Spherical Trigonometry

**This week, That’s Maths (TM007) describes various ways of dividing up the sphere. This is an important problem in geometry, biology, chemistry, astronomy, meteorology and climate modelling. Continue reading ‘Carving up the Globe’**

**In That’s Maths this week (TM004), we look at the problem of packing goods of fixed size and shape in the most efficient way. Packing problems, concerned with storing objects as densely as possible in a container, have a long history, and have broad applications in engineering and industry. **

**Johannes Kepler conjectured that the standard method used by grocers to pile oranges and gunners to stack cannon balls is the most efficient, but this conjecture was proved only recently by Thomas Hales. The mathematics involved in packing problems includes computational techniques, differential geometry and optimization algorithms. **

**The Foams and Complex Systems Group in Trinity College Dublin have recently discovered some new dense packings of spheres in cylindrical columns. An International Workshop on Packing Problems took place in TCD on 2-5 Sept. 2012. For more information, look here.**

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**This week’s That’s Maths article, at TM002, describes how Google’s PageRank software finds all those links when you enter a search word, by solving an enormous problem in linear algebra.**

**A comprehensive description of PageRank is given in the book Google’s PageRank and Beyond: The Science of Search Engine Rankings, by Amy N. Langville & Carl D. Meyer This book won an AAP Award in 2006 for Best Professional/Scholarly Book in Computer & Information Science.**