Author Archives: dougaj4

Another (very slow) way of computing pi

Posted on 24/01/2019 by dougaj4

The previous post included 100 Python code one-liners for calculating pi that recalculates in a fraction of a second.  The video below shows an alternative approach that is a little slower: How much slower?  If you had a computer that would … Continue reading →

Posted in Bach, Maths, Newton | Tagged , , | 2 Comments

mpmath for Excel

Posted on 13/01/2019 by dougaj4

mpmath has been mentioned in passing here before, but not in any detail.  The mpmath site says: mpmath is a free (BSD licensed) Python library for real and complex floating-point arithmetic with arbitrary precision. It has been developed by Fredrik … Continue reading →

Posted in Excel, Link to Python, Maths, PyXLL, UDFs, VBA, xlwings | Tagged , , , , , , , , | 7 Comments

Transferring large arrays with Pyxll

Posted on 05/01/2019 by dougaj4

Pyxll is a commercial Excel add-in linking Excel and Python.  The latest version  offers greatly improved performance in transferring data between Excel and Python as Numpy arrays, amongst many other new features and improvements. To check what this means in practice, … Continue reading →

Posted in Arrays, Excel, Frame Analysis, Link to Python, PyXLL, UDFs, VBA | Tagged , , , , , , | Leave a comment

Scarborough Fair

Posted on 31/12/2018 by dougaj4

Scarborough Fair is a very old song, according to Wikipedia dating back at least to 1670, and probably much earlier.  Here are three versions from the mid-sixties. The first from Martin Carthy was released in 1965, on his first album: The … Continue reading →

Posted in Bach | Tagged , , , | 2 Comments

More updates to ArcSpline and IP2

Posted on 27/12/2018 by dougaj4

I have uploaded version 2.18 of the IP2 spreadsheet to: IP2.zip The new version includes updates to the IP, IP_4, and ArcSpline functions, as described below.  The download is free and includes full open-source code. The IP and IP_4 functions find … Continue reading →

Posted in Arrays, Coordinate Geometry, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , | 2 Comments