Category Archives: Excel

Yet more pendulums

Posted on 24/06/2011 by dougaj4

Following Dynamically Defined Dancing Pendulums, another three versions of the dancing pendulum theme.  First a POV-RAY version by PM 2Ring, complete with reflections and shadows: POV-Ray Pendulums (click to open in a new window) and an interactive Javascript version: Javascript pendulums by PM2Ring (click … Continue reading →

Posted in Animation, Excel, Newton, Ray Tracing | Tagged , , , , | 1 Comment

Debugging VBA …

Posted on 22/06/2011 by dougaj4

… especially User Defined Functions (UDF’s). This post (and most likely several to follow) was prompted by a recent discussion at Daily Dose of Excel about various alternative debugging techniques.  It reminded me (if I had ever known) of the Debug.Assert … Continue reading →

Posted in Excel, UDFs, VBA | Tagged , , , | 2 Comments

High Speed Blog …

Posted on 07/06/2011 by dougaj4

… brought to you via Smurf on Spreadsheets If you want your spreadsheets to go faster, Charles Williams is the man to tell you how to do it.  Charles has recently started a blog on the subject: FastExcel Well worth … Continue reading →

Posted in Excel, VBA | Tagged , , | Leave a comment

Dancing Pendulums

Posted on 25/05/2011 by dougaj4

This animation was produced in response to a video of real pendulums performing similar tricks: Not having an animation program I thought I’d use the finite element program Strand7.  Modelling the pendulums was easy, just 15 beam elements with a … Continue reading →

Posted in Animation, Excel, Finite Element Analysis, Newton | Tagged , , , | 5 Comments

Using LinEst() on data with gaps

Posted on 14/05/2011 by dougaj4

A comment on Using LINEST for non-linear curve fitting asked if it was possible to use the function on data with gaps.  There are several options: Copy and sort the data to remove the gaps. Use the chart trendline function Use … Continue reading →

Posted in Arrays, Excel, UDFs, VBA | Tagged , , , , | 40 Comments