EWTILENI@PUCC.BITNET (02/21/87)
(Courtesy SPECTROGRAM Magazine - the new magazine on the block for all
Color Computer Users)
by Eric W. Tilenius
GRAFPLOT Version 2.0, from Hawkes Research Services, is a good
package suitable for many graphing applications - from budgets to
business, and statistics to scientific applications. It is a full
featured graphing program, with many options and advanced data-handling
abilities, but the buyer should be aware that GRAFPLOT
only produces line graphs. It will not draw bar charts, pie graphs,
scatter graphs, or any other type of graph. Instead, the author has
chosen to concentrate on one of the most common types of graphs (line
graphs) in order to make a program that gives the user much greater
graphing power. Despite a few minor complaints of mine, and a few
features which the program lacks (most of which are included in the new
version of GRAFPLOT which should be available by the time you read
this), I feel that GRAFPLOT is an excellent program and is worth
consideration by anyone who has need of a graphing program. GRAFPLOT
requires 32K and will work on a Color Computer 1, 2, or 3 (in CoCo 2
mode) with at least 1 disk drive.
GRAFPLOT comes on an unprotected disk and is accompanied by a 37
page manual telling the program's features, providing examples, and
showing how sample graphs will look. The manual may be a bit hard to
understand for someone who is not familiar either with graphing
techniques or other graphing programs, but otherwise does a pretty
good job of explaining how to use GRAFPLOT. A prompting mode helps the
first time user enter data more easily.
Once you've become more familiar with GRAFPLOT, you'll see the many
options which it offers. The program can, for instance, read your data
from disk (from saved spreadsheet data in certain formats), from
cassette, from the keyboard, or it can generate data from a mathematical
function you give it. You can have 1 or 2 "Y" (vertical)
axes, with each sharing the same or different "X" (horizontal) values.
You can sort data, select automatically or manually scaled axes, and
even perform what is known as "binomial smoothing" to take out
irregularities in your data. GRAFPLOT will also integrate your data to
find the area under the curve represented by your data between two
specified points on the X-axis.
Once you've entered and modified your data GRAFPLOT will plot a
graph for you. Again, many professional options are at your fingertips.
The program will print a title for the graph for you on the screen
(using full upper- and lowercase), and will let you type in labels for
the X-axis and one or both of the Y-axes. You may then
choose from a wide variety of graphing symbols for each set of data,
including points, open or solid squares and diamonds, and circles,
triangles, or crosses. Then, GRAFPLOT offers you the option of
connecting these points with a single line, double line, or no line at
all. And, whatever symbol and line pattern you choose, GRAFPLOT will
display it in parentheses next to your Y-axis label. You may graph all
of your data, or enlarge a section of your data to appear on the axes.
Once you've defined exactly what you wish GRAFPLOT to do with your
data, it will go ahead and draw the graph on a PMODE 4 screen
(high-resolution for the CoCo 2). It does so quickly, but not at a
lightning speed, as the program is written in BASIC. GRAFPLOT
automatically "tics" your graph, or marks it with appropriate values
along the axes. For instance, if you were dealing with percentages from
0 to 100%, GRAFPLOT will mark the side of the Y axis with evenly spaced
numbers from 0 to 100, and write the numbers in, too. This produces a
very nicely-labeled final product.
Once you've drawn your masterpiece, you have (ah, yes) more options.
First, you can overlay another set of data on top of the already-drawn
graph. You can also save the graphics screen with the graph on it for
either touching up with a graphics editor or printing with one of the
screen print programs not supported by GRAFPLOT. This
is not the same as saving the raw data, which is also an available
option. At this point, you may also return to the main menu to alter
your data, rescale axes, etc. Finally, you can print your finished
product directly from GRAFPLOT. A Radio Shack screen dump program is
included, or you may purchase one of several Custom Software
Engineering's printer drivers. Either of these will integrate with
GRAFPLOT to allow you to print your graphs without ever leaving the
program. Or, as I mentioned before, the graph can be saved and printed
with your favorite dump program, such as PRINT MASTER or HARDCOPY.
What I like most about GRAFPLOT is it's power and flexibility. In
addition to those features mentioned above, you can "chain" data to
produce a series of graphs (of up to 200 points each) for large amounts
of data, have the "tic" marks extend across the entire screen to produce
a grid-like effect, list the data on printer or screen, and
more. The tutorial section in the manual, while a tiny bit hard to
follow for new users at first, helps ease you into use of this program.
Sample graphs are printed at the end of the manual to display how
different graphing options affect how the finished product will look.
There are, however, some areas in which I felt GRAFPLOT could stand
improvement. The first is in its error handling. It is possible to enter
data that will cause the program to crash or mess-up. In addition, at
one point in the program, I was confused when asked for "X-1" (the first
X value), then asked again for "X-1". What the
program actually should have been asking for in the second case was
"Y-1" (the first Y value to correspond with X-1), but for some reason,
the obvious error was never caught in my copy. There is, too, an error
in the documentation. It states that you can EDIT the program line that
contains the data generating function, then "GO TO 543" if you
want to save data already in memory. Unfortunately, any time you EDIT or
change a program line, all data in memory is lost. The manual should
have told the user to save data first, before modifying the program
line.
Be warned that all of GRAFPLOT's power comes at a price. It is
somewhat tricky to manage all these options to create exactly the graph
you desire, and the manual doesn't make all the options crystal clear.
So, you may have to do a little playing around before you get the hang
of using GRAFPLOT. Yet, I feel the benefits of having more
power outweigh the time it takes learning to use the program. I guess
the final decision comes down to whether you make only an occasional
graph and want simplicity, in which case this is not the program for
you, or whether you really want control over your graphs and the ability
to produce sophisticated graphical representations. GRAFPLOT
shines at the latter.
My only other gripes with GRAFPLOT Version 2.0 concern some of its
limitations. Happily, Hawkes Research Services has announced a new
version of GRAFPLOT - now available - which makes this program even more
versatile and professional. I was going to say that limiting the user to
having two sets of data on the screen at once was a severe
drawback. But now, with the new version, Hawkes claims that you can have
UNLIMITED overlay of data, plus 291 graphing symbols. I was going to
comment that GRAFPLOT's disk read format was a bit limited, but the new
version let's you read data from most all the popular spreadsheets,
according to Hawkes. Plus, included, free with your
order is the screenprint program of your choice. Finally, the new
GRAFPLOT features moving average calculation, handy for many graphs
where you wish to calculate the average for many data points.
GRAFPLOT has been around on the CoCo market for several years now,
and has proved itself as a reliable performer. Version 2.0, which I
received for review, is excellent in itself, and the new version, if it
does all that Hawkes says it will, should set a new standard in CoCo
graphing programs. I was also impressed with the trust and
support which Hawkes gives to the customer. In addition to quality
service, Hawkes offers a 30-day money-back guarantee if not satisfied.
On a scale of 1-5 (1=poor, 5=excellent), I would give GRAFPLOT Version
2.0 a rating of 4. And, while I haven't seen the newer version in
action, I can anticipate giving that a 4.5 or so.
My final wish for this program is that, eventually, Hawkes rewrite
it to take advantage of the CoCo 3's 640 by 192 graphics mode. With all
of GRAFPLOT's outstanding features, and the CoCo 3's better graphics,
this program would be truly spectacular.
GRAFPLOT is available from Hawkes Research Services, 859 Stanford
Avenue, Oakland, CA 94608. Phone (415) 547-7557. The program costs $40
on tape, or $45 on disk (I would strongly recommend the disk version if
you have a drive), plus $3 Shipping and handling. Please specify your
printer when ordering. You may also purchase a demo on disk or
tape for $5; if you decide to order GRAFPLOT, you'll receive a $5 credit
towards the program.
- ERIC -
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