Category Archives: Newton

More Python Traps

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

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

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

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Paul Kelly and Joni Mitchell

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

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Asymmetric Catenary Function

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

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

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