Category Archives: UDFs

More 3D Intersections and 3D plotting function

Following the previous post, I have added several new functions connected with intersections of lines and planes, and a function to generate a perspective plot from 3D coordinates.  The new functions have been added to the IP2.xls worksheet, which can … Continue reading

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

3D Intersections

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

Double Exponential Quadrature

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

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

ALGLIB linear and polynomial fitting functions

As promised here: Fitting high order polynomials this post presents details of four Excel User Defined Functions (UDFs) linking with ALGLIB functions for least squares fitting of linear and polynomial functions.  The new functions are: AL_Linest: AL_LinestCW: AL_PolyFit: and AL_PolyFitCW: These functions have been added … Continue reading

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