Category Archives: UDFs

Rabbits, Foxes, and Lorenz Attractors

Posted on 23/02/2014 by dougaj4

Following comments here and here I have added two examples to the ODE Solver spreadsheet showing use of the ODE function to solve systems of differential equations with two or more coupled equations. The new version (including full open source … Continue reading →

Posted in AlgLib, Differential Equations, Excel, Maths, Newton, UDFs, VBA | Tagged , , , , , , , , | 2 Comments

Cubic splines with horizontal data

Posted on 16/02/2014 by dougaj4

Following a request here I have modified my cubic spline functions to accept input arranged  in rows as well as columns.  By default the output arrays will have the same orientation as the range of interpolation X values, but I have also added … Continue reading →

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

Beam actions and deflections, 3D or 2D

Posted on 01/02/2014 by dougaj4

Two new functions have been added to the ConBeamU spreadsheet, last discussed here. The new version can be downloaded from ConBeamU.zip, including full open-source code. The new functions, BeamAct3D and BeamAct2D calculate forces, moments, deflections and rotations along a 3D … Continue reading →

Posted in Beam Bending, Excel, Finite Element Analysis, Frame Analysis, Newton, Strand7, UDFs, VBA | Tagged , , , , , , | 2 Comments

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