Author Archives: dougaj4

Evaluating Pi …

Posted on 12/04/2009 by dougaj4

… to 15 decimal places in one easy step (or not too difficult step). In my previous post one of the examples given of the use of the Gaussian Quadrature function was to evaluate the value of Pi.  Let’s look at … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 4 Comments

Gaussian Quadrature

Posted on 10/04/2009 by dougaj4

The previous post on integration provided an Excel User Defined Function (UDF) to perform numerical integration using Simpson’s Rule or the Trapezoidal Rule.  A third method is Gaussian Quadrature which is often much more accurate and/or quicker than Simpson’s Rule.  The UDF GaussInt() … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , | 27 Comments

WolframAlpha

Posted on 10/04/2009 by dougaj4

WolframAlpha is coming! From the link: “Some might say that Mathematica and A New Kind of Science are ambitious projects. But in recent years I’ve been hard at work on a still more ambitious project—called Wolfram|Alpha. And I’m excited to … Continue reading →

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Another update to IP.xls

Posted on 07/04/2009 by dougaj4

Following some suggestions from Mike Seymour I have modified my polyline intersection function, and added a new version. The changes are: The data ranges for the new function, IP4(), are entered as four separate ranges, so the X and Y … Continue reading →

Posted in Excel, Maths, UDFs, VBA | Tagged , , , , | 1 Comment

Connected

Posted on 04/04/2009 by dougaj4

7:55 Thursday evening at Sydney’s Enmore Theatre for the Eric Bibb concert due to start 8:00, and the house is barely half full. An hour and a half later after the support act and an intermission the house is packed, … Continue reading →

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