Category Archives: Excel

3D Intersections

Posted on 19/03/2011 by dougaj4

Following a discussion at the Eng-Tips Forum, I have written an Excel User Defined Function (UDF) to find the intersection point of two 3D line segments.  The UDF has been added to the IP2 spreadsheet, which is available for free … Continue reading →

Posted in Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 7 Comments

More links

Posted on 17/03/2011 by dougaj4

One of the nice things about running a blog is that visitors leave the address of the site that lead them here, and if you follow these links back it sometimes takes you to fascinating sites that you would  never … Continue reading →

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

XNumbers and Tropical Events

Posted on 10/03/2011 by dougaj4

My on-line friend Al Vachris recently sent me a link to the Tropical Events site, which features a detailed analysis of the orbital motion of the Earth and the other bodies of the solar system, all done in Excel, and … Continue reading →

Posted in Excel, Maths, Newton, Numerical integration | Tagged , , , | 16 Comments

Double Exponential Quadrature

Posted on 07/03/2011 by dougaj4

Graeme Dennes has updated his Tanh-Sinh Quadrature spreadsheet to include Double Exponential Quadrature.  His brief notes are given below, and more details and links to background information are included in the download file. ================================================================= Double Exponential Quadrature UDFs added to Tanh-Sinh Quadrature … Continue reading →

Posted in Excel, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , | 1 Comment

Non linear regression – 2; ALGLIB functions

Posted on 05/03/2011 by dougaj4

The previous post looked at using the Excel Solver to fit a non-linear equation to a given set of data, using the least squares method.  This approach is reasonably convenient and straightforward, but it has a number of disadvantages: The … Continue reading →

Posted in AlgLib, Concrete, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , | 8 Comments