MrWhy,
Since I am taking a lunch break at this moment, I wanted to read a little in the forums. I love the last three samples. I will look at your challenge a little later, but I wanted to send this modification to you. It is a slight modification to you last "Variant 6 - 6 coupled oscillators" demo. I REMed out the CLS and _DISPLAY commands and changed the color variable (col). I am trying to visualize the results a little different.
'@ 6 coupled oscillators
DEFDBL A-Z
_FULLSCREEN
SCREEN 12
WINDOW (-.5, -.5)-(.5, .5)
dt = .001
cd = .251
col = 1
x1o = cd: y1o = -cd
x2o = cd: y2o = cd
x3o = -cd: y3o = cd
x4o = -cd: y4o = -cd
x5o = 0: y5o = cd
x6o = 0: y6o = -cd
x1 = x1o: x2 = x2o: x3 = x3o: x4 = x4o
y1 = y1o: y2 = y2o: y3 = y3o: y4 = y4o
x5 = x5o: x6 = x6o
y5 = y5o: y6 = y6o
x1 = x1 + .2: '***** try .04
'x3 = x3 - .2
'x2 = x2 + .1
'x4 = x4 - .1
v1y = .00003
'v3y = .000023
'v2y = .000023
'v4y = .000023
'v1x = .00012 '***** try rem out this line
m1 = 1: m2 = 1.01: m3 = 1.02: m4 = 1.03: m5 = 1.04: m6 = 1.05
nsq = .0000000125 '****try 00000012,11, 09,08 etc
n1sq = nsq: n2sq = nsq: n3sq = nsq: n4sq = nsq: n5sq = nsq: n6sq = nsq
n = nsq / 25
n12sq = n: n13sq = n: n14sq = n: n15sq = n: n16sq = n
n23sq = n: n24 = n: n25sq = n: n26sq = n
n34sq = n: n35 = n: n36sq = n
n45sq = n: n46sq = n
n56sq = n
ChangeColorDelay = 875000
ChangeColorMoment = 0
DO
accn1x = -n1sq * (x1 - x1o) - n12sq * ((x1 - x2) - (x1o - x2o)) - n13sq * ((x1 - x3) - (x1o - x3o))
accn1x = accn1x - n14sq * ((x1 - x4) - (x1o - x4o)) - n15sq * ((x1 - x5) - (x1o - x5o)) - n16sq * ((x1 - x6) - (x1o - x6o))
accn1y = -n1sq * (y1 - y1o) - n12sq * ((y1 - y2) - (y1o - y2o)) - n13sq * ((y1 - y3) - (y1o - y3o))
accn1y = accn1y - n14sq * ((y1 - y4) - (y1o - y4o)) - n15sq * ((y1 - y5) - (y1o - y5o)) - n16sq * ((y1 - y6) - (y1o - y6o))
v1x = v1x + accn1x / m1
v1y = v1y + accn1y / m1
accn2x = -n2sq * (x2 - x2o) - n12sq * ((x2 - x1) - (x2o - x1o)) - n23sq * ((x2 - x3) - (x2o - x3o))
accn2x = accn2x - n24sq * ((x2 - x4) - (x2o - x4o)) - n25sq * ((x2 - x5) - (x2o - x5o)) - n26sq * ((x2 - x6) - (x2o - x6o))
accn2y = -n2sq * (y2 - y2o) - n12sq * ((y2 - y1) - (y2o - y1o)) - n23sq * ((y2 - y3) - (y2o - y3o))
accn2y = accn2y - n24sq * ((y2 - y4) - (y2o - y4o)) - n25sq * ((y2 - y5) - (y2o - y5o)) - n26sq * ((y2 - y6) - (y2o - y6o))
v2x = v2x + accn2x / m2
v2y = v2y + accn2y / m2
accn3x = -n3sq * (x3 - x3o) - n23sq * ((x3 - x2) - (x3o - x2o)) - n13sq * ((x3 - x1) - (x3o - x1o))
accn3x = accn3x - n34sq * ((x3 - x4) - (x3o - x4o)) - n35sq * ((x3 - x5) - (x3o - x5o)) - n36sq * ((x3 - x6) - (x3o - x6o))
accn3y = -n3sq * (y3 - y3o) - n23sq * ((y3 - y2) - (y3o - y2o)) - n13sq * ((y3 - y1) - (y3o - y1o))
accn3y = accn3y - n34sq * ((y3 - y4) - (y3o - y4o)) - n35sq * ((y3 - y5) - (y3o - y5o)) - n36sq * ((y3 - y6) - (y3o - y6o))
v3x = v3x + accn3x / m3
v3y = v3y + accn3y / m3
accn4x = -n4sq * (x4 - x4o) - n24sq * ((x4 - x2) - (x4o - x2o)) - n34sq * ((x4 - x3) - (x4o - x3o))
accn4x = accn4x - n14sq * ((x4 - x1) - (x4o - x1o)) - n45sq * ((x4 - x5) - (x4o - x5o)) - n46sq * ((x4 - x6) - (x4o - x6o))
accn4y = -n4sq * (y4 - y4o) - n24sq * ((y4 - y2) - (y4o - y2o)) - n34sq * ((y4 - y3) - (y4o - y3o))
accn4y = accn4y - n14sq * ((y4 - y1) - (y4o - y1o)) - n45sq * ((y4 - y5) - (y4o - y5o)) - n46sq * ((y4 - y6) - (y4o - y6o))
v4x = v4x + accn4x / m4
v4y = v4y + accn4y / m4
accn5x = -n5sq * (x5 - x5o) - n25sq * ((x5 - x2) - (x5o - x2o)) - n35sq * ((x5 - x3) - (x5o - x3o))
accn5x = accn5x - n15sq * ((x5 - x1) - (x5o - x1o)) - n45sq * ((x5 - x4) - (x5o - x4o)) - n46sq * ((x6 - x4) - (x6o - x4o))
accn5y = -n5sq * (y5 - y5o) - n24sq * ((y5 - y2) - (y5o - y2o)) - n35sq * ((y5 - y3) - (y5o - y3o))
accn5y = accn5y - n15sq * ((y5 - y1) - (y5o - y1o)) - n45sq * ((y5 - y4) - (y5o - y4o)) - n56sq * ((y5 - y6) - (y5o - y6o))
v5x = v5x + accn5x / m5
v5y = v5y + accn5y / m5
accn6x = -n6sq * (x6 - x6o) - n26sq * ((x6 - x2) - (x6o - x2o)) - n36sq * ((x6 - x3) - (x6o - x3o))
accn6x = accn6x - n16sq * ((x6 - x1) - (x6o - x1o)) - n46sq * ((x6 - x4) - (x6o - x4o)) - n56sq * ((x6 - x5) - (x6o - x5o))
accn6y = -n6sq * (y6 - y6o) - n26sq * ((y6 - y2) - (y6o - y2o)) - n36sq * ((y6 - y3) - (y6o - y3o))
accn6y = accn6y - n16sq * ((y6 - y1) - (y6o - y1o)) - n46sq * ((y6 - y4) - (y6o - y4o)) - n56sq * ((y6 - y5) - (y6o - y5o))
v6x = v6x + accn6x / m6
v6y = v6y + accn6y / m6
x1 = x1 + v1x
y1 = y1 + v1y
x2 = x2 + v2x
y2 = y2 + v2y
x3 = x3 + v3x
y3 = y3 + v3y
x4 = x4 + v4x
y4 = y4 + v4y
x5 = x5 + v5x
y5 = y5 + v5y
x6 = x6 + v6x
y6 = y6 + v6y
PSET (x1, y1), col
PSET (x2, y2), col + 1
PSET (x3, y3), col + 2
PSET (x4, y4), col + 3
PSET (x5, y5), col + 4
PSET (x6, y6), col + 5
ChangeColorMoment = (ChangeColorMoment + 1) MOD ChangeColorDelay
IF ChangeColorMoment = 0 THEN
'_DISPLAY
col = ((col + 1) MOD 10) + 1
'CLS
END IF
k$ = INKEY$: IF k$ <> "" THEN SYSTEM
LOOP