Add runup_models.py

Started with Stockdon 2006, but will probably need to add more.

src/analysis/runup_models.py

@@ -0,0 +1,23 @@
+import numpy as np
+
+def stockdon06(Hs0, Tp, beta):
+
+    Lp = 9.8 * Tp ** 2 / 2 / np.pi
+
+    S_ig = 0.06 * np.sqrt(Hs0 * Lp)
+    S_inc = 0.75 * beta * np.sqrt(Hs0 * Lp)
+
+    # Dissipative conditions
+    if beta / (Hs0/Lp)**(0.5) <= 0.3:
+        setup = 0.016 * (Hs0 * Lp) ** 0.5
+        S_total = 0.046 * (Hs0 * Lp) ** 0.5
+        R2 = 0.043 *  (Hs0 * Lp) ** 0.5
+    else:
+        setup = 0.35 * beta * (Hs0 * Lp) ** 0.5
+        S_total = np.sqrt(S_inc ** 2 + S_ig **2)
+        R2 = 1.1 * (setup + S_total / 2)
+
+    return R2, setup, S_total, S_inc, S_ig
+
+if __name__ == '__main__':
+    pass