A picture is worth 1,000 words but how many numbers? (business graphics package) (evaluation) L.L. Beavers.
A Picture Is Worth 1,000 Words But How Many Numbers?
I like numbers. That makes me a little strange, because most people don't. In a sense, they're right: numbers don't communicate. Consider Ms. Big.
A Session with Apple II Business Graphics
As an executive with Chewie Gobbles Confections, Inc., you have been asked to design a presentation for Ms. Big, executive vice president of your parent company, International Munchies. Ms. Big is your basic bottom-line sort of person--she wants specifics, she wants to see them clearly and quickly, and she wants to know what they mean to her. You are supposed to turn some sales and margin numbers into a presentation that will make her smile. You have one hour.
First, feed the computer. You put the Apple II Business Graphics disk into drive 1 and a data disk you have named CHEWIE: into drive 2, and turn on the power. After some whirring of disks, and some noises that sound like the program disk is being initialized (one of Apple's technical support people assures me this is normal), you get a prompt.
You type EDIT to invoke the editor, and after a few seconds the number one and a question mark appear on the screen. You want time on the horizontal axis, so you enter the sales figure this way:
1: ? "1977', 1. 06
2: ? 1978, 1. 40
3: ? 1979, 1. 80
4: ? 1980, 2. 27
5: ? 1981, 2. 71
6: ? END
The word END exits the editor, and the computer responds with:
5 LABELS LOADED
5 POINTS LOADED
You save the data with the command SAVE CHEWIE:SALES. Now you type CLEAR to clear the work file and EDIT to reinvoke the editor, and you enter your gross margin figures:
1: ? "1977', 41
2: ? 1978, 37
3: ? 1979, 38
4: ? 1980, 38
5: ? 1981, 40
6: ? END
You save these data on your CHEWIE disk with the command SAVE CHEWIE:MARGINS.
The computer now has all of your data.
Elapsed time: 5 minutes. You decide to look at the sales data first, so you type:
The program responds with:
5 LABELS LOADED
5 POINTS LOADED
How about a bar graph? You type DRAW BAR, and the following graph appears on your screen.
Now for some titles:
SET TITLE "CHEWIE GOBBLES CONFECTIONS, INC.'
SET HORIZONTAL TITLE "FISCAL YEAR' SET VERTICAL TITLE "MILLIONS'
The title should be more specific, so:
SET FLOATING TITLE "GROSS SALES, 1977-1981'
A box appears on the graphics screen, and you use the U (up), D (down), L (left), and R (right) keys to position the title under the title of the graph. The results look like this:
That looks fine. You save this display by typing SAVE SCREEN CHEWIE:SALES. Elapsed time: 11 minutes.
Now for the margin figures:
SET VERTICAL RANGE 0 45
What you get looks like this:
Not so good. The fluctuations in the margin figures get lost among the trees. Maybe a line graph would be better.
CLEAR VERTICAL RANGE
Now we can see what's happening, and it isn't all good. Ms. Big should be told what happened in 1978:
SET FLOATING TITLE "1978 SUGAR UP 60%'
You position that title, and type in the remaining titles: SET TITLE "CHEWIE GOBBLES CONFECTIONS, INC.'
SET VERTICAL TITLE "% OF SALES'
SET HORIZONTAL TITLE "FISCAL YEAR'
SET FLOATING TITLE "GROSS MARGINS, 1977-1981'
The result of your efforts looks like this:
You save the graph by typing, SAVE SCREEN CHEWIE:MARGINS.
You are now ready to print the results for your boss's approval. Total elapsed time: 20 minutes. Have a cup of coffee.
Which Graphs You Need
The man who wrote of office buildings, "Form ever follows function,' could have been talking about graphics. In graphics "function' means communication: communication between you and your data (interpretation), and communication between you and other people (presentation).
For both interpretation and presentation, you need three kinds of graphs: line graphs, bar graphs, and pie charts.
You need line graphs to depict trends, and Apple II Business Graphics offers extensive line graph capabilities.
First, you want to be able to plot as many points as you need on a single curve. With Apple II Business Graphics the number of points is limited more by practicality than by the program. I have plotted as many as 400 points on one curve.
Second, you want to compare curves by plotting them on the same graph. Of course, the curves must be distinguishable. Apple II Business Graphics provides two methods: eight different symbols for the plot points and six different curve types. Here, too, practicality is the limit: you could plot 15 distinguishable curves, but no one would read them.
Third, you want control of the ranges of the numeric scales. The scale can have a tremendous effect on what a graph appears to say. Plot on a large scale and fluctuations and trends will look small; plot on a small scale and they will look large. Apple II Business Graphics lets you choose a scale that accurately represents your data.
Apple II Business Graphics offers one more option useful with line graphs. You can color in the area between a curve connecting your data points and the horizontal axis. This is called "shading.'
One common use of shading is to emphasize the difference between two sets of numbers. Suppose I am interested in the prices of unleaded gasoline and of diesel fuel, and in the difference between them. Then I might use this graph:
Unfortunately, there is no command for filling in the area between curves. I did the display by first filling the area under the unleaded gasoline price curve. Then I filled the area under the diesel price curve with the color set to black, thus erasing that shading. The remaining shaded area is between the two curves. I then drew the two curves and drew a horizontal line at 115 (since the horizontal axis had been partially erased).
Those are the most important line graphing capabilities, and they are all available--though perhaps requiring a little fudging. But you don't want to draw lines for the rest of your life do you?
When you have few numbers and large differences between them, try a bar graph. Bar graphs are properly drawn from a zero baseline, so small differences get lost. That's why we rejected the bar graph of gross margins for Ms. Big.
As with line graphs, the ability to plot more than one set of numbers on the same bar chart is useful. Apple II Business Graphics limits you to four data sets per graph. If both scales are numeric, you can use overlapping bars and plot more data sets, but the need rarely arises.
The bars can be vertical or horizontal. They can be filled, outlined, or both. Furthermore the filling or outlining can be done in your choice of colors (green, violet, white, orange, blue, or black). Even with a black-and-white display, colors can be used to vary the density of lines and shading.
You don't have control over the width of the bars. Rejoice. You don't want it. The program scales the width based on the number of bars being drawn. Practical applications for variable width bars are rare, and doing the scaling yourself can be a major nuisance.
Also not available is one option you might want--segmented bars. The need for this kind of display is fairly common. It arises when you have a set of numbers that you want to show in a bar graph, but each number has two or more components that you also want to show. For example, suppose you are interested in the growth of the U.S. population, but you also want to see the urbanization of that population. You could represent the total population, the urban population, and the rural population as three data sets on a multiple bar graph, like this:
The problem with this is that the reader can't see that the total is the sum of the urban and rural populations. Until the reader knows this, the increasing proportion of the population living in cities is obscure. A much better display would be the following:
Besides being a clearer display of the data, this graph shows that cheaters sometimes prosper in computing. I said that Apple II Business Graphics has no option for producing segmented bar graphs, yet I have just shown you one. How? I cheat. First I entered the rural population data and drew a set of filled bars. Then I entered the total U.S. population data and drew another set of bars (in the same place) with the FILL set to OFF. The blank inside each bar is then the urban population.
Another way to show fractional parts of an aggregate is with a pie chart. Normally you use a pie when only the relative sizes of the fractions interest you. For example, the following chart shows U.S. energy production by source.
You don't control the size of the pie, nor can you overlay a pie on another chart. Unfortunately, neither can you highlight one of several slices by offsetting it from the rest.
But the essential capabilities are there. You can draw a pie with each slice clearly distinguishable from its neighbors. You can control the colors that create this distinction. The program automatically labels the slices, and you can put additional labels on the graph. You can even draw a pie with a slice missing, to show that your data don't cover the universe of interest.
One of the most appealing things about Apple II Business Graphics is the flexible way it handles titles for all these graphs. There are four flavors: a general title, a vertical title printed to the left of the vertical axis, a horizontal title printed below the horizontal axis, and floating titles--as many as you want--printed anywhere. Any of these titles can be printed in both upper- and lower-case characters, and 26 special characters (including trademark and copyright symbols) are also available.
The real beauty of this scheme is in the floating titles. You can print them horizontally or vertically, and you can use them to label curves in a line graph, bars in a bar graph, slices in a pie graph, or groups of points in a scatter plot. You can also use floating titles to add lines to the general title or a footnote below the graph.
In addition to drawing lines, bars, and pies, you can list descriptive statistics, develop a frequency distribution, "smooth' the data (unweighted moving average), or fit any of five curves (constant, line, parabola, logarithmic curve, or sine curve) to the data. You can even use the curve-fitting or smoothing options for forecasting, though I urge extreme caution--especially with parabolic and logarithmic curves.
There is also a "TAKE file' feature similar in concept to Apple DOS EXEC files: it automates a sequence of commands, executing them from a disk file as though the user had typed them from the keyboard. With this capability, Apple II Business Graphics has some of the features of an electronic slide show system.
Using the Program
We have discussed what Apple II Business Graphics can do, but how easy is it to make the program do it? We will look at that question in two parts. First, how easy is it to enter and manipulate the numbers? Second, how easy are the commands to remember and use?
Data Entry and Manipulation
Apple II Business Graphics defines data in terms of "points.' A point is a pair of coordinates, specifying a unique location on any graph. Either or both of these coordinates can be a label or a number.
You enter data to the program in a variety of ways. Most people will probably just use the program editor, but there are alternatives. For the VisiCalc fanatics in the audience, Apple II Business Graphics accepts data directly from VisiCalc print files. It also accepts files stored in the Data Interchange Format (DIF), and data from text files stored on DOS 3.2.1, DOS 3.3, or Pascal/Fortran disks. The manual includes details on the structure of these files.
But even fanatics will often find themselves using the editor. You probably got some idea of the editor from following the example for Ms. Big: you type the horizontal coordinate, type a comma, then type the vertical coordinate. An entry beginning with an alphabetic character is assumed to be a label, and numbers can be made labels by enclosing them in quotes.
Once entered, the data can be changed in several ways. You can CHANGE, DELETE, or INSERT with the editor. You can also transform the data mathematically by Adding, Subtracting, Multiplying, or Dividing either a constant or the values in a saved file. Logarithmic transformation is not offered, unfortunately. You also have a SHIFT function, which is equivalent to the "lead' and "lag' time-series functions. Finally, you have cumulative SUM and point-to-point DIFFERENCE functions available.
By now you probably have a general feel for the commands Apple II Business Graphics accepts, but notice the language in which they are written. In both vocabulary and structure it is similar to English. Commands begin with English verbs like EDIT, SET, DRAW, and MULTIPLY. A noun and sometimes a modifier to either the verb or the noun may be added, and the result sounds like an English sentence: EDIT LABELS, SET COLOR WHITE, DRAW PIE, MULTIPLY BY 100, and so on. Such a command language feels familiar, because it exploits the user's familiarity with his natural language.
Other advantages flow from the same source. For a language as flexible as this one, it is easy to learn and easy to remember. More important, it has the scope and simplicity that are jointly necessary for a comfortable, creative interaction with the computer. Since designing graphics is a creative process, this kind of interaction is a tremendous asset.
With all of the above features, you should be able to draw almost any graph you need on the high-resolution graphics screen. (Those with 80-column cards should test compatibility with Apple II Business Graphics--not all 80-column boards can display high-resolution images.) But can you put the graphs on paper?
Apple II Business Graphics will output to Apple Silentype and Qume Sprint 5 printers and to some plotters, according to the manual. For other printers, there are programs designed to print a high-resolution picture from the Apple memory. If you have one that uses Pascal-format files, you can print from screen files saved by Apple II Business Graphics. If your print program expects DOS 3.3 files, you can still use it: 1. Draw your graph, 2. Put your print program in drive 1, 3. Press RESET. When you press RESET, Apple II Business Graphics tries to reboot, and boots your graphics printer instead. Your graph should be intact on hi-res page 1 of memory, and you can then print it.
Probably the weakest part of Apple II Business Graphics is the way it manages disk space. As in Apple Pascal, deleted files leave gaps on the disk. Files must be stored in a set of contiguous storage blocks, so gaps created be deleting smaller files are usually unavailable for storing larger ones.
Despite what the manual says, Apple II Business Graphics tells you only how much total space is left on the disk. So, one day you will try to save a screen file (requiring 16 blocks of storage space) on a disk with 21 free blocks, and the SAVE command will fail (? VOLUME IS FULL). This means that the largest chunk of disk storage has less than 16 contiguous blocks in it. Worse, there is no utility in Apple II Business Graphics comparable to Pascal's Krunch--so you can't fix the problem. If you have Pascal, you can run the Pascal Filer against your Apple II Business Graphics data disks. If not, use more disks.
I have offered both kudos and criticisms in this article. As Ms. Big might ask, "What's the bottom line?'
Of course that question is never as simple as it sounds. In this case I think three evaluations are important: 1. Does the program do what a graphics program should, 2. Is it easy to use, and 3. What are the extras offered and the limitations imposed?
My answer to part one is a unqualified "Yes.' The essential business graphics are all there. The quality of your product is limited much more by the output device than by the program. With a pen plotter, you can produce professional quality business graphics.
Not only can you do what needs doing, but you can get it done quickly and easily. I like the feel of using this system. It doesn't get in your way. Rather, it efficiently handles the drudgery, so that you are free to sit there and create.
As far as extras and limitations are concerned, there are some important instances of both; but I judge the balance to be far on the plus side. The extra capabilities tend to be very useful, while the limitations tend to be more inconvenient than debilitating. I suppose that the computer will become the ideal knowledge tool when the least sophisticated user is more limited by his own ingenuity than he is by the system he is using. We aren't there yet, but I think that Apple II Business Graphics is a significant step in the right direction.
Table: Graph 1.
Table: Graph 2. CHEWIE GOBBLES CONFECTIONS, INC. GROSS SALES, 1977-1981
Table: Graph 3.
Table: Graph 4.
Table: Graph 5. CHEWIE GOBBLES CONFECTIONS, INC. GROSS MARGINS, 1977-1981
Table: Graph 6. U.S. MOTOR FUEL PRICES REGULAR UNLEADED GASOLINE VS. DIESEL FUEL
Table: Graph 7. URBANIZATION OF THE U.S. POPULATION 1950-1980
Table: Graph 8. URBANIZATION OF THE U.S. POPULATION 1790-1980
Table: Graph 9. U.S. ENERGY PRODUCTION, 1981
Products: Apple II Business Graphics (computer program)