AmigaBASIC Lissajous figure #shorts @DrDavesDiversions

Dr. Daves Diversions | AmigaBASIC Lissajous figure #shorts @DrDavesDiversions | Uploaded December 2021 | Updated October 2024, 7 minutes ago.
Nerding around making Lissajous figures in XY mode on the oscilloscope with my Amiga''s stereo channels and AmigaBASIC from 1986!

New Tank Mouse: some are scrolling randomly

Tandy Radio Shack TV Scoreboard Composite Mod and HDMI #SepTandy 2022 #VCFMidwest2022

PDP 11/23 running UNIX version 6 at VCF Midwest!

Clicky Keebs: IBM Model M vs. Everex Enhanced

Service Engine Soon: my 1989 Trans Am GTA

$C64 Turtle Graphics: Rotational Symmetries from Repeating Decimals #shorts Fun with Turtle Graphics on the Commodore 64 c. 1984! This is a visualization is of the value 1/7 (one-seventh), a rational number with a repeating decimal that forms a nice rotationally symmetric figure when its base 10 digits are used to determine the fraction of 360 degrees rotated before drawing the next line segment. Here is what I wrote today using HESwares Turtle Graphics II (c) 1983. Because this language does not have arrays, I could not simply drop the digits of 1/7 (0.14285714285714...) into an array like they do using python in the Numberphile videos (linked below). Instead, I decided to calculate each digit on each loop iteration (DRAW). Note that C64s INT() function is actually floor() and that this language, like C64 BASIC, does not have a modulo operator, which is why the calculations are more verbose. This is in the 64s 320x200 mode (HIRES!). Currently the fraction (1/7) is hard-coded, as well as the length of the repeating run (7) and the number of iterations (100). 1 HIRES 2 SET HEADING TO 0 3 MOVE TO 80-130 4 PEN DOWN 5 CALCULATE X=0 6 LABEL DRAW 7 FORWARD 50 8 CALCULATE Y=X-(INT(X/7)*7) 9 CALCULATE A=INT((1/7)*(10^Y)) 10 CALCULATE D=36*(A-INT(A/10)*10) 11 TEST IF (D=0) 12 IF TRUE JUMP POSTROT 13 ROTATE LEFT D 14 LABEL POSTROT 15 CALCULATE X=X+1 16 TEST IF (X=100) 17 IF FALSE JUMP DRAW 18 STOP Related: Plotting Pi and Searching for Mona Lisa - Numberphile https://www.youtube.com/watch?v=tkC1HHuuk7c The specific figure I plot is shown beginning at 7m20s: https://www.youtube.com/watch?v=tkC1HHuuk7c&t=7m20s The Plotting of Beautiful Curves (Euler Spirals and Sierpiński Triangles) - Numberphile https://www.youtube.com/watch?v=kMBj2fp52tA The Turtles are Coming! by David Malmberg, pp. 26-28, Commodore Power-Play, 1982, Issue 2, V1, N02, Fall (issuu.com) https://issuu.com/astarothduke/docs/commodore_power-play_1982_issue_02_v1_n02_fall David Malmberg Interview (brasslantern.org) http://brasslantern.org/community/interviews/malmberg-b.html q(D.M.: Sort of. I wrote and published a product for the Commodore-64 and VIC-20 titled TurtleGraphics, which sold approximately 80,000 copies and was translated into French and Spanish. It was actually published by a company called HESware, which I helped found. Turtle Graphics was a LOGO-like language/product designed to teach programming skills to kids from six to sixty.) ANTIC Interview 285 - Jay Balakrishnan, HESWare (audio) https://ataripodcast.libsyn.com/antic-interview-285-jay-balakrishnan-hesware$

Electroware C64 PSU heavy-duty mod (30W DC power)