Category Archives: Newton

More Python Traps

Posted on March 30, 2020 by

I recently posted on some Python Traps, focussing on code where changes in the values of sub-routine arguments were not reflected in the calling routines.  The reverse can also be a problem: if an array, a, is passed to a … Continue reading →

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

LinEstGap with non-linear functions

Posted on March 14, 2020 by

The LinEstGap user defined function (UDF) allows the built-in Linest function to be used on data with empty cells or hidden rows, returning results that agree with the chart trend-line function, which automatically ignores blank cells and hidden data.  It … Continue reading →

Posted in Arrays, Curve fitting, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , | 1 Comment

Katherine Johnson, NASA Legend

Posted on February 26, 2020 by

Cartoon by Steve Breen from The San-Diego Union Tribune. More on Katherine Johnson.

Posted in Maths, Newton | Tagged , , | Leave a comment

Paul Kelly and Joni Mitchell

Posted on February 8, 2020 by

Leading Australian singer-songwriter Paul Kelly is about to release a powerful new single that tackles Australia’s lack of action on climate change and environmental destruction. Entitled Sleep, Australia, Sleep, Kelly says the song is both “a lament in the form … Continue reading →

Posted in Bach, Climate | Tagged , , , | Leave a comment

Asymmetric Catenary Function

Posted on January 31, 2020 by

Back in 2009, I posted a user defined function (UDF) to generate a catenary curve, that could be used together with the Excel Solver to generate a curve of a specified span and sag: A catenary function Following a discussion … Continue reading →

Posted in Coordinate Geometry, Curve fitting, Excel, Maths, Newton, UDFs, xlwings | Tagged , , , , | Leave a comment

Column buckling under multiple loads

Posted on January 20, 2020 by

Following another buckling discussion at Eng-tips I have modified my Frame4-buckle spreadsheet to allow input of multiple axial loads at any point along the column, along with any number of sections with different section properties.  Background on the method used … Continue reading →

Posted in AlgLib, Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Newton, UDFs, VBA | Tagged , , , , , , , , , | Leave a comment

Trinity Bridge and Bridge of the Month

Posted on January 9, 2020 by

Bill Harvey has been doing a monthly report on historical bridges for many years, but recent issues have the added interest of interactive 3D models of the selected bridges. The Trinity Bridge at Crowland in South Lincolnshire is an excellent … Continue reading →

Posted in Arch structures, Historic Bridges, Newton | Tagged , , , | Leave a comment