Author Archives: dougaj4

Alglib/Python linear and non-linear fitting functions

Posted on 23/07/2014 by dougaj4

I have updated the Alglib spline-matrix spreadsheet to use the latest Alglib release, using the Python version, in conjunction with the Excel-Python add-in. To use the spreadsheet requires: Python ver 2.7 (or 2.6) Excel-Python Alglib with Python interface In addition … Continue reading →

Posted in AlgLib, Excel, Link to Python, Newton, UDFs, VBA | Tagged , , , , , , | 4 Comments

Evaluating text and Integration with Python and ALGLIB

Posted on 07/07/2014 by dougaj4

Following the previous post on evaluating mathematical functions entered as text on the spreadsheet, I have now written a spreadsheet with similar functionality using Python functions, and the Excel-Python add-in.  Also included are integration functions using the SciPy Python library, … Continue reading →

Posted in AlgLib, Arrays, Excel, Link to Python, Maths, Newton, Numerical integration, NumPy and SciPy, UDFs, VBA | Tagged , , , , , , | 1 Comment

The Dome of Santa Maria del Fiore in Florence; new links

Posted on 01/07/2014 by dougaj4

Earlier this year the on-line edition of National Geographic posted an article on: Mystery of Florence’s Cathedral Dome May Be Solved The wording of the article owes more to journalistic hyperbole than anything else, but it includes a link to an … Continue reading →

Posted in Arch structures, Bach, Dome Structures, Newton | Tagged , , , | Leave a comment

Evaluating text – update

Posted on 28/06/2014 by dougaj4

One disadvantage of the spreadsheet style interface is that even simple formulae are difficult to check.  For instance, the deflection of a cantilever loaded at the end is given by: F*L^3/(3*E*I) which is much easier to read than the Excel … Continue reading →

Posted in AlgLib, Excel, Maths, Newton, Numerical integration, UDFs, VBA | Tagged , , , , , , , | 5 Comments

Reinforced Concrete – ULS capacity under combined axial load and biaxial bending

Posted on 19/06/2014 by dougaj4

I have modified the ULS Design Functions spreadsheet, last presented here, to analyse sections subject to bi-axial bending, and non-symmetrical sections.  The new version makes use of the routines for splitting any section defined by XY coordinates into trapezoidal layers, described … Continue reading →

Posted in Beam Bending, Concrete, Excel, Newton, UDFs, VBA | Tagged , , , , , , | 13 Comments