Homework Assignment Sep 1, 2025

Resultant from Event Samples — Homework (Ideas Only)

Given (per item): a list of angles (degrees) observed in one time window for a single system.

Task: compute the resultant vector and derived quantities, with A=1 and P=1 to isolate ideas.

Pipeline

M = \sum e^{i\theta_t}
C=|M|, phi=arg(M)
j=C cos phi, k=C sin phi
|E|=sqrt(1+k^2), r=1/|E|, S=ln r

Notes. Evaluate trig in radians; display angles in degrees. Only the sine projection k reaches the denominator; the cosine projection j never does. Here r is radius and S is Surprise.


Report for each item

C, phi, j, k, |E|, r, S and an “alignment” score |k|/C with the rule of thumb: Strong >=0.80, Moderate [0.40,0.80), Weak <0.40.


Problems (angles in degrees)

  1. MLK-like cluster
    {68, 72, 75, 77, 70, 73, 74, 69, 76, 71}
  2. Everyday circles
    {25, 28, 30, 32, 29, 31, 27, 33, 26, 34}
  3. Perfect-storm orientation
    {90, 90, 90, 90, 90, 90, 90, 90, 90, 90}
  4. Pure realization
    {0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
  5. Balanced opposite crowds
    {0, 0, 0, 0, 0, 180, 180, 180, 180, 180}
  6. Uniform decagon (full spread)
    {0, 36, 72, 108, 144, 180, 216, 252, 288, 324}
  7. Small angle, strong j
    {10, 8, 12, 9, 11, 7, 13, 10, 8, 12}
  8. Split at ±30° (equal counts)
    {30, 30, 30, 30, 30, −30, −30, −30, −30, −30}
  9. Lopsided 30° vs 210°
    {30, 30, 30, 30, 30, 30, 210, 210, 210, 210}
  10. Three-fold symmetry
    {0, 0, 0, 0, 120, 120, 120, 120, 240, 240, 240, 240}

Answer Key (rounded to three decimals)

  1. N = 10,  C = 9.987,  φ = 72.500°,  j = 3.003,  k = 9.525,  |E| = 9.578,  r = 0.104,  S = −2.259,  alignment = 0.954 → Strong.
    Imaginary component in denominator: k = 9.525.
  2. N = 10,  C = 9.987,  φ = 29.500°,  j = 8.693,  k = 4.918,  |E| = 5.019,  r = 0.199,  S = −1.613,  alignment = 0.492 → Moderate.
    Imaginary component: k = 4.918.
  3. N = 10,  C = 10.000,  φ = 90.000°,  j = 0.000,  k = 10.000,  |E| = 10.050,  r = 0.100,  S = −2.308,  alignment = 1.000 → Strong.
    Imaginary component: k = 10.000.
  4. N = 10,  C = 10.000,  φ = 0.000°,  j = 10.000,  k = 0.000,  |E| = 1.000,  r = 1.000,  S = 0.000,  alignment = 0.000 → Weak.
    Imaginary component: k = 0.000.
  5. N = 10,  C = 0.000,  φ = undefined,  j = 0.000,  k = 0.000,  |E| = 1.000,  r = 1.000,  S = 0.000,  alignment = 0.000 → Weak.
    Perfect cancellation in this lens.
  6. N = 10,  C = 0.000,  φ = undefined,  j = 0.000,  k = 0.000,  |E| = 1.000,  r = 1.000,  S = 0.000,  alignment ≈ 0.000 → Weak.
    Full rotational symmetry cancels.
  7. N = 10,  C = 9.995,  φ = 10.000°,  j = 9.843,  k = 1.736,  |E| = 2.003,  r = 0.499,  S = −0.695,  alignment = 0.174 → Weak.
    Imaginary component: k = 1.736.
  8. N = 10,  C = 8.660,  φ = 0.000°,  j = 8.660,  k = 0.000,  |E| = 1.000,  r = 1.000,  S = 0.000,  alignment ≈ 0.000 → Weak.
    Vertical parts cancel; horizontal parts add along 0°.
  9. N = 10,  C = 2.000,  φ = 30.000°,  j = 1.732,  k = 1.000,  |E| = 1.414,  r = 0.707,  S = −0.347,  alignment = 0.500 → Moderate.
    Imaginary component: k = 1.000.
  10. N = 12,  C = 0.000,  φ = undefined,  j = 0.000,  k = 0.000,  |E| = 1.000,  r = 1.000,  S = 0.000,  alignment = 0.000.
    Three equal clusters at 0°, 120°, 240° cancel exactly (classification not meaningful when C = 0).

Reminder. Add unit arrows first; split once; only k reaches the denominator. If C≈0 report phi undefined and note |E|=1, r=1, S=0. To detect a two-fold split, recompute with doubled angles before summing; for three-fold, triple the angles.

Author: John Rector

John Rector is the co-founder of E2open, acquired in May 2025 for $2.1 billion. Building on that success, he co-founded Charleston AI (ai-chs.com), an organization dedicated to helping individuals and businesses in the Charleston, South Carolina area understand and apply artificial intelligence. Through Charleston AI, John offers education programs, professional services, and systems integration designed to make AI practical, accessible, and transformative. Living in Charleston, he is committed to strengthening his local community while shaping how AI impacts the future of education, work, and everyday life.

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