Category Archives: UDFs

ExcelPython2, Alglib and Spline-Matrix update

Posted on 12/09/2014 by dougaj4

The ExcelPython add-in, offering easy access to Python code from Excel VBA, has had a major update to Release 2.  The new version provides new features and simpler installation, but has some incompatibilities with code written for the previous  version, so the … Continue reading →

Posted in AlgLib, Excel, Link to Python, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , | 4 Comments

Extending complex UDFs with simple VBA

Posted on 05/09/2014 by dougaj4

One of the advantages of writing spreadsheet applications in the form of User Defined Functions (UDFs) is that the UDF may be used on the spreadsheet in the same way as a built-in function, allowing applications to be modified and extended … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | 3 Comments

Using the VBA ParamArray keyword

Posted on 30/08/2014 by dougaj4

The recently posted SolvePoly function makes use of the VBA ParamArray keyword, which allows an arbitrarily long list of arguments to be passed to another function.  I have not made great use of this in the past, but since the … Continue reading →

Posted in Excel, Maths, Newton, UDFs, VBA | Leave a comment

Numerical Integration; Tanh-Sinh Quadrature v. 4.2

Posted on 23/08/2014 by dougaj4

The latest version (4.2) of the numerical integration spreadsheet by Graeme Dennes is now available for download from Tanh_Sinh Quadrature. For more details of the background see: Faster Integration with the Tanh-Sinh Method and subsequent posts on this subject. In addition to … Continue reading →

Posted in Excel, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , , , , | 2 Comments

Solving polynomials – update

Posted on 14/08/2014 by dougaj4

The polynomial spreadsheet (details here) provides functions to solve polynomial equations of any order; using an “exact” method for up to quartic, and an iterative procedure for higher orders.  The input for the functions requires the equation coefficients to be … Continue reading →

Posted in Arrays, Excel, Maths, UDFs, VBA | Tagged , , , , , | 3 Comments