潮汐（天文）調和分析

Harmonic analysis decomposes the tide into astronomical constituents; each constituent is described by an amplitude H and a phase lag g, while its speed σ is fixed by astronomy (M₂ 28.9841°/h, S₂ 30.0000, K₁ 15.0411, O₁ 13.9430). Enter the harmonic constants plus the local mean sea level and the tool synthesizes the water level curve, picks high and low waters and reports the range. F < 0.25 means a regular semidiurnal tide, 0.25–1.5 mixed mainly semidiurnal, 1.5–3.0 mixed mainly diurnal, above 3.0 regular diurnal. Take the constants from tidal tables; results are for operational planning only.