Category Archives: Maths

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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Spreadsheets all the way down

Posted on 22/02/2016 by dougaj4

If you need another reason to attend Excel Summit South, watch this video, and discover that mobile phones are spreadsheets all the way down.    

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Use Matplotlib from Excel with xlwings

Posted on 14/02/2016 by dougaj4

Xlwings is another free and open source package allowing communication between Excel and Python.  It now incorporates ExcelPython, and is included in the Anaconda Python package, so will support my ExcelPython based spreadsheets after installation of xlwings using: conda install … Continue reading →

Posted in Drawing, Excel, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, VBA | Tagged , , , , , , | 9 Comments

Tanh-Sinh Quadrature via F2PY – Part 3

Posted on 06/02/2016 by dougaj4

For the last of the current series on combining Fortran, Python and Excel with F2PY and ExcelPython I have updated the xlSciPy spreadsheet to include two other variants of the Tanh-Sinh function: Quad_TSi integrates a non-periodic function over a semi-infinite … 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 →

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