Category Archives: Maths

Two MaxAbs functions

Posted on 20/01/2014 by dougaj4

Excel does not have a built-in function to find the maximum absolute value of a range, perhaps because the Max() and Abs() functions can be combined in an array function: =Max(Abs(datarange)) This solution has a number of drawbacks however: The … Continue reading →

Posted in Arrays, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , | 9 Comments

Solving Quadratic, Cubic, Quartic and higher order equations; examples

Posted on 14/01/2014 by dougaj4

A previous post presented a spreadsheet with functions for solving cubic and quartic equations, and this has been extended with another function solving higher order polynomials.  The functions are actually very easy to use, but the documentation in the spreadsheets is quite brief, … Continue reading →

Posted in Arrays, Excel, Link to Python, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , , | 13 Comments

Converting from global to local coordinates (and vice versa)

Posted on 08/01/2014 by dougaj4

In 3D structural analysis (as well as many other applications) it is necessary to convert section properties, forces, and deflections between coordinate systems defined by individual structural members (local coordinates) and the common coordinate system defining the entire structure (global … Continue reading →

Posted in Excel, Finite Element Analysis, Frame Analysis, Link to Python, Maths, UDFs, VBA | Tagged , , , , , , , | 22 Comments

Xlls, Maths and Plots; some useful links

Posted on 11/11/2013 by dougaj4

Two from regular commenter here, Keith Lewis: Excel xll add-in library: This is a library for creating xll add-ins for Excel from 97 through 2013. It makes every feature of the latest Excel SDK available to you including the big … Continue reading →

Posted in Coordinate Geometry, Excel, Link to dll, Maths, Newton | Tagged , , , | 3 Comments

Python for VBA users- 6; Using Pysparse with Excel

Posted on 29/10/2013 by dougaj4

Previous Python Post The analysis of structural frames requires the solution of large sparse matrix systems, which rapidly becomes very time consuming using a VBA based solver, especially for 3D analysis.  I have previously presented versions of my frame analysis … Continue reading →

Posted in Arrays, Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Link to Python, Maths, Newton, NumPy and SciPy, VBA | Tagged , , , , , | 1 Comment