Editing can be dangerous

Handling of numerical data is greatly simplified when it is represented in graphic form.

However, the process of converting numerics into graphics is often complex and error prone.

To help, there are programs which do all the slog as well as allowing data to be manipulated as required.

Well known programs of this type for CP/M systems or indeed the BBC Micro with Z80 have price tags well into triple figures. So when I received Datamaster priced at £14.90. I approached it with trepidation.

Datamaster consists of four programs on tape which are chained in as required. The first program prints the title page and assembles a short machine code dump.

The second program - Unidatam - handles univariate data. When loaded, the program prints a menu. Through one of the options, you can enter your data then display it in the form of a pie chart or a histogram.

As expected, you can place any text to accompany the diagrams by moving a cursor around the screen and typing the text.

This is where you'll realise that this program is rather badly designed. If you suddenly decide to change or add some data while editing the screen and go back to the menu, all your handiwork is lost for ever.

This means that you must save the screen every time you want to amend data. Just to aggravate matters, there are some striking omissions. For instance, you cannot explode part of a pie chart, you cannot print text vertically with rotated text and you cannot shade in areas for emphasis. Most surprising of all was the omission of an easy automatic axis labelling facility. The manipulation of data is rather clumsy in that you enter the data number you want to change and input the new value without seeing the old value.

The same sort of criticism goes for the other two programs. Bidatam - handles bivariate data - and Multicart - handles multiple bivariate data.

One good thing about this package was its manual. It is clear and precise even though it is cheaply produced on a dot matrix printer, although mine may be a pre-production copy.

Although this is easily the cheapest program of this type for the BBC Micro, and I quite liked Multicart, there are superior disc-based programs costing only slightly more.

Shingo Sugiura