"""
Wavelength
===========

Wave-length for a given frequency can be calculated using .. function::helpers.wavelength.

"""

import numpy as np
from mafredo.helpers import wavelength
import matplotlib.pyplot as plt

T = np.linspace(1, 20)
omega = 2 * np.pi / T

for wd in (5, 10, 20, 40, 100, 0):
    wave_lengths = [wavelength(om, waterdepth=wd) for om in omega]
    if wd == 0:
        name = "deep water"
    else:
        name = f"waterdepth = {wd}m"

    plt.plot(T, wave_lengths, label=name)
plt.legend()
plt.xlabel("Wave period [s]")
plt.ylabel("Wave length [m]")
plt.ylim(0, 200)
plt.grid()
