Tag Archives: UDF

xlwings 0.7.1, dictionaries, and optional arguments

Posted on 08/04/2016 by dougaj4

xlwings 0.7.0 was published at the beginning of March, and introduced direct support for Python dictionaries, which I have used to demonstrate various options for dealing with optional arguments in Excel User Defined Functions (UDFs).  The latest version, 0.7.1, published … Continue reading →

Posted in Curve fitting, Excel, Link to Python, Maths, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , , , | 1 Comment

xlScipy with xlwings

Posted on 20/03/2016 by dougaj4

Following a new release of xlwings, I have updated the xlScipy spreadsheet to work with it, and added a few new features: The Matplotlib routines to plot a function entered as text (previously posted as xlMatPlot.zip) have been incorporated on … Continue reading →

Posted in Excel, Link to Python, Maths, Newton, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , , , | Leave a comment

Cubic splines with descending x

Posted on 01/03/2016 by dougaj4

In response to a recent comment, I have modified the CSpline2 spreadsheet so that the CSplineA and CHSplineA functions will accept x values list in descending order, as well as ascending.  For more details of the background to the functions, … Continue reading →

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Tanh-Sinh Quadrature via F2PY – Part 2

Posted on 01/02/2016 by dougaj4

Lets look at some details of the coding. The original code (available here) includes routines “intdeini” to generate an array of points and weights of the quadrature formula, and “intde” to carry out the integration of any supplied function “f”. … Continue reading →

Posted in Excel, Link to dll, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , , , | Leave a comment

Tanh-Sinh Quadrature via F2PY

Posted on 31/01/2016 by dougaj4

Fast and accurate numerical integration routines based on the Tanh-Sinh method are available as Excel VBA based functions in the Tanh_Sinh Quadrature spreadsheet by Graeme Dennes.  Graeme’s VBA code is based on open source Fortran code by Takuya Ooura, which … Continue reading →

Posted in Excel, Fortran, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , , , | Leave a comment