Microsoft Excel is such a flexible and powerful tool that you can use in all manner of situations. Below, is a screen shot of an Excel spreadsheet application we have developed that encapsulates the quadratic equation. It plots the quadratic graph over a specified range, and displays the chart data. The coefficient input for the quadratic is entered by the user and also displayed. Then, immediately after the user has entered the coefficient data, the graph updates and the solutions for the quadratic equation are calculated and shown in spreadsheet cells B6, and C6. There is also a button control on the spreadsheet to take you to the developers home page which, in this case, is us, at gwycon.com!

Quadratic equation spreadsheet. Layout of controls, data, and chart.

As mentioned above, whenever the spreadsheet updates automatically the quadratic equation solutions are calculated immediately and displayed to the user. This happens by means of a custom programmed spreadsheet function to calculate the solutions to a quadratic equation. If the solutions turn out to be complex, the function returns the string “Err!”. continue

This is a simple Flash based paint program that shows how fully functional applications can be put together quickly and deployed to the web for easy access – this example is coded using ActionScript 2.0. This is the great thing about Flash, the immediate availability of content. Once it has been created, all you have to do is embed the Flash file into a web page – and that’s it! No installation needed to be done by the user, they can use the application straight away.

Here below, we have a paint application that can be used to create a drawing by using the mouse. Different colours are available, and the line thickness and opacity can be controlled. The user can also clear the picture and start again!

Try it now! Click on the canvas and drag the mouse around. Select different colours and line properties. Enjoy!

The core code needed to render the canvas area is shown below: continue

Microsoft Excel is a very versatile tool and can be used for many different purposes. The example we have here is a volume calculator for some simple geometric shapes. The user can enter values for the parameters (such as side length, or radius), and the corresponding volume is updated automatically.

Click to enlarge

However, rather than just display the parameters and calculated volume, it is often more user friendly to format the spreadsheet area with diagrams, and the odd splash of colour here and there!

Also, this example does not make use of any macros, but could be easily extended to do so. The volume equation for each shape is entered directly into worksheet cells but could be stored in macro code instead in the form of a custom worksheet function. This function could then be called as necessary, just like a standard worksheet function.