A Basic Planetary System – video preview

June 20, 2011

Since not everybody has Excel and more and more people are on the dumbed down new versions (2007 and 2010) I am presenting these previews to give the readers a feel of the real speed and feel of some of the models in older Excel versions (in this case 2003). This preview refers to an older model.


Playing Sounds in Excel Using VBA – part #2

March 3, 2011

This section explains how to create a compound sound effect from elementary sounds. In the first example (two macros), the sound is played in a loop which is a native internal loop within the “PlaySound” function (using the flag option: SND_LOOP = &H8). A second function (the “Beep” function) creates a tone generator with adjustable frequency and play time. The Beep function is also used in a fourth macro, creating a sound which goes…


Playing Sounds in Excel Using VBA – part #1

March 2, 2011

This tutorial is an introduction to VBA sound playing macros in Excel. The sound effects can be used in various scientific and engineering models or in games. It first shows the general syntax of a sound playing macro and few sources of downloading free .wav sound files. The first demo macro plays a short sound a single time and the second macro plays a series of three sounds. In order…


How to make a game of PONG in Excel – part #6

March 1, 2011

In the previous section a special ball return formula was implemented. Bat #1 was assigned the y-coordinate of the ball and in this way a very simple opponent algorithm was implemented. The problem with this algorithm is that by having Bat #1 perfectly tracking the ball, the opponent was unbeatable. This section shows how to add adjustable skill levels to the virtual pong opponent.


Casual Introduction to Numerical Methods – spring-mass-damper system model – part#5

February 22, 2011

In this tutorial, most of the calculations for the numerical simulation a SMD (spring-mas-damper) system will be consolidated into a single formula, the coordinate formula. In this case, in order to calculate the coordinate at the end of a any time step, we will need just the coordinates from the previous two time steps and of course the input parameters (constants). These input parameters are: mass, damping ratio, spring constant and time…


Creating a Speedometer in Excel, Part #2 – tutorial

February 11, 2011

The previous tutorial (first half) explained how to download a speedometer picture from www.flickr.com and how to alter it (delete the needle) using a freeware called Gimp (similar to Photoshop). – The model replaces the deleted needle from the picture with a moving one created from a chart line. – This second half of the tutorial explains the geometry, trigonometry and VBA code used to build a new rotating speedometer…


Creating a Speedometer in Excel, Part #1 – tutorial

February 10, 2011

This is the first half of a tutorial which shows how to create a speedometer in Excel. The model is essentially a 2D scatter chart having as background the picture of a speedometer dial downloaded from www.flickr.com. Before using the photograph you need to erase the arm of the speedometer from the picture using Photoshop or other photo editing software. In the model I replaced the deleted arm with a moving arm created from…


A Family of Speedometers in Excel

February 9, 2011

Hi guys, by popular demand, this is a file containing five different animated speedometers and a tachometer (rpm-meter). I can recognize two models: a Toyota Camry and a Ford Crown Victoria. They work great. The rest I am not sure what they are, I would appreciate if you tell me. Just leave a comment. The model works in all versions of Excel. Cheers, George


Casual Introduction to Numerical Methods – a spring-mass-damper system model – part#3

February 5, 2011

Here is the third part of a tutorial in both elementary dynamics and numerical methods. It is written at a basic level and it shows you how to set up a dynamic model for numerical solving of simple differential equations.   The dynamic model makes use of an infinite loop, which make the calculations advance in time. Instead of a large table with formulas, this time we have a small number of…