Weave, centered disturbance — Georg Nees, 1969

Dissertation 1969 · pp. 261 / 264

ALGOL 60

'BEGIN'
'COMMENT' GEWEBE STOERUNG
ZENTRIERT.,
'REAL' NK, ZK, F.,
'INTEGER' P, Q.,
'REAL' 'ARRAY' A,B(/-12..12,-8..8/).,
JA1.=JA2.=-1.,
JE1.=JE2.=1.,
JI1.=JS3., JI2.=JS4.,
NK.=5., ZK.=200.,
'FOR' P.=-12 'STEP' 1 'UNTIL' 12 'DO'
'BEGIN'
  'FOR' Q.=-8 'STEP' 1 'UNTIL' 8 'DO'
  'BEGIN'
    F.=ZK/(7*SQRT(P*P+Q*Q)+NK).,
    A(/P,Q/).=7*P+J1*F.,
    B(/P,Q/).=7*Q+J2*F
  'END'
'END'.,
'FOR' P.=-12 'STEP' 1 'UNTIL' 12 'DO'
'BEGIN'
  LEER(A(/P,-8/),B(/P,-8/)).,
  'FOR' Q.=-7 'STEP' 1 'UNTIL' 8 'DO'
    LINE(A(/P,Q/),B(/P,Q/))
'END'.,
'FOR' Q.=-8 'STEP' 1 'UNTIL' 8 'DO'
'BEGIN'
  LEER(A(/12,Q/),B(/12,Q/)).,
  'FOR' P.=11 'STEP' -1 'UNTIL' -12 'DO'
    LINE(A(/P,Q/),B(/P,Q/))
'END'.,
CLOSE
'END' GEWEBE STOERUNG ZENTRIERT.,

This page · drawing kernel

JavaScript

JI1 = JS3; JI2 = JS4;
JA = -1; JE = 1;
NK = 5; ZK = 200;
F = ZK / (7*sqrt(P*P+Q*Q) + NK);
A[P][Q] = 7*P + J1()*F;
B[P][Q] = 7*Q + J2()*F;
// At the origin F = 40, at the rim ≈ 2.

P. 261: between figures 44 and 46 the disturbance should not merely grow, but become macro-innovative — dependent on distance from the origin. Factor F inflates J1 and J2 at the centre; the rim stays calm. JS3 and JS4 from p. 122. Sheet rotated 90° as in the scan.