Heathkit H-100 or IBM PC programs in GWBASIC, BASICA
The code listings are in Heathkit H-100 GWBASIC, which was the same as BASICA except for differences related to graphics
display modes. The H-100 was always in graphics mode, so a mode didn't have to be selected. On the IBM PC, it is necessary to set
a mode. Most or all of these should be easy to make PC-compatible by adding a color graphics mode selection of "SCREEN 12" near
the top of the program. In some of these programs that line is already present, commented out.
Each link below goes to the project page, which has a more complete description and code listing.
Programs that display graphics or generate graphics files (mostly fractal images)
|IFS fractal graphic generator
||AUTORAND.BAS continuously generates random IFS variables and displays the associated
A second version of the program runs faster but has fewer features. A
third reads an .IFS file and generates its image. The page also links
to a brief overview of IFS fractal generation and to programs that convert
from rectangular coordinates to polar and back.
|Logistic map bifurcation diagram
||BIFURCAT.BAS shows Robert May's logistic map bifurcation diagram, as described in
Making A New Science, by James Gleick.
|Diffusion limited aggregation
||DLA3.BAS simulates diffusion limited aggregation. Particle randomly wanders
around the screen. When it collides with boundary, it sticks, creating tree
or fern-like structures.
|Strange attractor of Henon
||HENON.BAS produces graphic image of the strange attractor of Henon, regarding
|The chaos game
||CHAOSGAM.BAS uses a random walk to generate areas with fractal boundaries. A second
program draws a donut shape.
||Strange attractor? Probably not, but a waveform appears on the screen.
|Normal distribution graphic demonstration
||NORMAL.BAS builds a normal distribution at the bottom of the screen (the dropped
marbles also show their trails as they fall), but has the "sticky" routines
from DLA, so it makes strange treelike formations at the screen bottom,
instead, in a vaguely normal distribution.
|Graphic display of instability in outputs of iterated equation
||PARABOLA.BAS is a graphic display of equation instability. The later iterations create a parabola shape.
Programs that transform or manipulate graphics files
|Display graphics using GWBASIC BLOAD
||Two programs to display .PIC files that were saved by AUTORAND.BAS or
other programs. One displays a single file; the other automatically displays
consecutively-numbered .PIC files.
Miscellaneous other programs
||Plots points from data files to an on-screen graph in graphics mode, 640 x 225.
|Koch curve math
||KOCHMATH.BAS does a calculation associated with the Koch curve (snowflake). All it
really does it print some lines of numbers, but those numbers show that the
fractional dimension of the curve is the limit towards which the increased
Print mailing labels
||Two trivial BASIC programs to print mailing labels.