Category Archives: Maths

Trigonometric Functions in VBA – Update

In this post from February a set of VBA trigonometric functions were presented, using the derivations given on the Microsoft Developer Network site: Derived Math Functions Unfortunately two of the functions were wrong; the correct versions are shown below: Inverse Secant … Continue reading

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , | 5 Comments

Linking Excel to Fortran – 2

In this post the procedures described for C++ here will be replicated for Fortran: The spreadsheet, fortran source code, and compiled dll described in this code may be downloaded from Cubic.zip As always, it is better to use the downloaded code, … Continue reading

Posted in Excel, Fortran, Link to dll, Maths, UDFs, Uncategorized, VBA | Tagged , , , , , | 23 Comments

Finding Prime Numbers with Excel, and using Array Formulas

Download Primes.zip. Several of the puzzles at Project Euler (see previous post) require the finding of prime numbers, for instance what is the 10,001th prime number?  Searching the Web for some ready made solutions I found this array formula at … Continue reading

Posted in Arrays, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 28 Comments

Project Euler

Whilst tag-surfing I discovered Project Euler, which looks like fun for people who enjoy mathematical puzzles.  Here’s what they say about themselves: ” What is Project Euler? Project Euler is a series of challenging mathematical/computer programming problems that will require … Continue reading

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Dog Tessellations

An intruiging tessellation from a dog with a way with words Also a variety of tessellations from MC Escher. And while we are on tessellations, here is an animated tadpole tessellation posted by the dog’s father (who, strangely, does not seem … Continue reading

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