REAL Sinusoidal Functions

There are sinusoidal functions everywhere in the world. Here's an example on how the water tide shows sinusoidal similarities

Divine's Dock, South Carolina
33.5417° N, 79.0283° W

2010-02-18 5:05 AM EST 0.23 feet Low Tide
2010-02-18 6:57 AM EST Sunrise
2010-02-18 8:52 AM EST Moonrise
2010-02-18 10:22 AM EST 3.82 feet High Tide
2010-02-18 5:21 PM EST 0.10 feet Low Tide
2010-02-18 6:03 PM EST Sunset
2010-02-18 10:29 PM EST Moonset
2010-02-18 10:43 PM EST 4.19 feet High Tide
2010-02-19 5:47 AM EST 0.38 feet Low Tide
2010-02-19 6:56 AM EST Sunrise
2010-02-19 9:23 AM EST Moonrise
2010-02-19 10:57 AM EST 3.68 feet High Tide
2010-02-19 6:00 PM EST 0.16 feet Low Tide
2010-02-19 6:04 PM EST Sunset
2010-02-19 11:29 PM EST 4.19 feet High Tide
2010-02-19 11:29 PM EST Moonset

Like all sinusoidal functions, you find the equation first

1.) Sin or Cos? - cos

2.) Sinusoidal Axis -

3.) Amplitude - 4.19-.1=2.145

4.) Period - 12.12 hrs.

5.) Phase shift - 3.71

The equation