SSM-Clock Stamp – UTC Day Boundary (continuity sanity) (5.9)

Objective. Confirm that the clock wraps cleanly at midnight UTC and that rasi_idx updates only when a 30° cusp is crossed — deterministic, plain ASCII.

Rules (must)

  • UTC only; parse iso_utc = "YYYY-MM-DDThh:mm:ssZ" (no subseconds; reject 23:59:60).
  • Angle from UTC:
    wrap360(x) = x - 360*floor(x/360)
    theta_deg = wrap360( (unix_seconds / 86400) * 360 )
    rasi_idx = floor(theta_deg / 30)
  • One-second increment in angle:
    theta_deg(t+1s) = wrap360( theta_deg(t) + 360/86400 )

Steps (deterministic)

  1. Pick T = YYYY-MM-DDT23:59:59Z.
  2. Compute at T and T+1s = (YYYY-MM-DD + 1 day)T00:00:00Z:
    • theta_T = wrap360( (unix(T) / 86400) * 360 )
    • theta_T1 = wrap360( (unix(T+1s) / 86400) * 360 )
    • Check increment: theta_T1 == wrap360( theta_T + 360/86400 )
    • rasi_T = floor(theta_T / 30); rasi_T1 = floor(theta_T1 / 30)
  3. Stamp two tiny files at T and T+1s; verify both stamps.

Expected

CLOCK_OK=true for both
theta_T1 == wrap360(theta_T + 360/86400)
rasi_T1 == rasi_T            # unless a cusp at 30*k was crossed
# if cusp crossed:
rasi_T1 == (rasi_T + 1) mod 12
VERDICT=PASS for both

Notes & edge cases

  • Leap second banned: do not test 23:59:60Z; stamps claiming :60 are invalid.
  • The increment 360/86400 is exactly 0.004166... degrees per second; do not round before applying wrap360.
  • rasi_idx changes iff theta_deg crosses a multiple of 30 degrees between T and T+1s.

Why this matters
Clean wrap and sector transitions guarantee that the Shunyaya Symbolic Mathematical Clock Stamp behaves predictably across day boundaries, keeping verification deterministic and ASCII-simple.

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