updated GCI checkes

Author: browniea

mhkit/river/io/d3d.py

@@ -1073,6 +1073,19 @@ def calculate_grid_convergence_index(
     gci: float
         Grid Convergence Index (GCI).
     """
+
+    # Validate inputs
+    if not (np.issubdtype(type(refinement_ratio), np.number)):
+        raise TypeError("refinement_ratio must be a numeric values")
+    if not (np.issubdtype(type(factor_of_safety), np.number)):
+        raise TypeError("factor_of_safety must be a numeric values")
+    if not (np.issubdtype(type(order), np.number)):
+        raise TypeError("order must be a numeric values")
+    if not (np.issubdtype(fine_grid.dtype, np.number) and np.issubdtype(coarse_grid.dtype, np.number)):
+        raise TypeError("fine_grid and coarse_grid must contain numeric values")
+    if fine_grid.shape != coarse_grid.shape:
+        raise ValueError("fine_grid and coarse_grid must have the same shape")
+    
     # Calculate the approximate relative error
     error = np.abs((fine_grid - coarse_grid) / fine_grid)