Category Archives: Arrays

Scipy linear algebra functions in Excel

Posted on 30/05/2023 by dougaj4

The file pyLinAlgfuncs3.zip has open source Python code allowing the Scipy linear algebra functions to be called from Excel using the pyxll add-in. It also includes all the Python code to perform LU decomposition, as discussed in the previous post., … Continue reading →

Posted in Arrays, Excel, Finite Element Analysis, Frame Analysis, Link to Python, Maths, Newton, NumPy and SciPy, PyXLL, UDFs | Tagged , , , , , , | 2 Comments

Working with Python polynomials from Excel

Posted on 22/10/2022 by dougaj4

Python polynomial functions have several features that require manipulation of data passed from Excel: In Python polynomial coefficients are listed in order of increasing powers of x (a + bx + cx^2 …), but they are more usually listed with … Continue reading →

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

A Match Function Bug …

Posted on 08/10/2022 by dougaj4

… or at least, a non-intuitive feature of the MATCH function, that may give inconsistent results. This post is based on a discussion at EngTips. The problem under discussion was to find the number of the first and last rows … Continue reading →

Posted in Arrays, Excel | Tagged , , , | 3 Comments

Installing Python and pyxll from scratch

Posted on 26/09/2022 by dougaj4

Updated 28th September 2022. Matplotlib latest version OK. I recently installed Python and pyxll (plus the required additional libraries) on a new computer, which raised a few problems with incompatible versions, so here is a summary of what worked (as … Continue reading →

Posted in Animation, Arrays, Charts, Coordinate Geometry, Differential Equations, Excel, Finite Element Analysis, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, Python Pandas, PyXLL, UDFs | Tagged , , , , , , , , , , , , , , | 2 Comments

Contour plots with Excel and Matplotlib – 2 

Posted on 30/12/2021 by dougaj4

The procedures discussed in the previous post required the contour data to be arranged on a regular rectangular grid, with the data points listed in a 2D array. As far as I know there is no built in alternative in … Continue reading →

Posted in Arrays, Charts, Excel, Finite Element Analysis, Link to Python, Newton, NumPy and SciPy, PyXLL, Strand7, UDFs | Tagged , , , , | 1 Comment