Category Archives: Maths

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 →

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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 →

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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 →

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Alglib/Python spline functions update

Posted on 02/08/2014 by dougaj4

The Excel Spline-Matrix spreadsheet has now been updated with several new spline interpolation functions.  See Alglib/Python linear and non-linear fitting functions for links to download and install the necessary Excel-Python and Alglib files.  Also required is Python version 2.7 or 2.6. The … Continue reading →

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Alglib/Python spline functions

Posted on 25/07/2014 by dougaj4

Continuing from the previous post, the new xl_Spline-Matrix.zip spreadsheet includes functions for 1D and 2D linear and cubic splines. The basic 1D spline allows  for output of linear splines, or 5 different types of cubic spline, as listed above. Output may … Continue reading →

Posted in AlgLib, Excel, Link to Python, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , , , , , , , | 1 Comment