Spatial Modelling Techniques in Microsoft Excel

We begin by considering the expectations of the creators of VisiCalc, the first spreadsheet. The emphasis is on the nature of the spreadsheet grid. The grid is taken as a presentational method for showing a solution to a Sudoku puzzle. We consider methods or approaches for the solution. We look at the relationship between this model and academic papers on the methods for describing and categorising end-user models generally. We consider whether the type of model described here should be categorised separately. The complexity of the model is reviewed in the context of commendations to minimise overly sophisticated presentational constructs and formulae. 1. BACKGROUND Nature and Role of a Spreadsheet The philosophical question of the core nature of a spreadsheet is not prominent in the literature. Its practical uses are so obvious that we have just got on and used it – for good or ill. However, Bricklin and Frankston, the spreadsheet creators [Power, 2004], did not consider it primarily as an accountancy program: as was the case with the first spreadsheet-type concepts built for mainframe computers. In particular, Frankston stated in an email to Power: "The grid provided the simplifying structure that made it a spreadsheet as opposed to a more general surface." The importance of the grid, as opposed to a table or similar database like structure, is huge. It allows spatial freedom with the placement of the grid and conceptual freedom over the nature and contents of the grid (e.g. numbers, text, formulae, images, colours etc.) The grid structure is often obscured by other elements. There is a great deal of redundancy between the Microsoft business programs [Cook, 2010]. Primarily, Word is for word processing, Excel is the spreadsheet, Access is the database etc. But Excel has database features, Word has spreadsheet features, etc. The emphasis on database functions within spreadsheets has obscured the functional elements of the grid style paradigm. This paper contributes to redressing the balance, by:  Selecting a model that employs a grid structure to determine the relationship between individual identities  Using numeric identities rather than number values, thus forcing a different programmatic approach to the management of the model