#!/usr/bin/env python3

import matplotlib.pyplot as plt
import numpy as np
import os
from matplotlib.ticker import MultipleLocator

def detach_display():
    t, x, y, h, u, v  = np.loadtxt(
        'hu_specific_points.dat', delimiter='\t', unpack=True)
    fig, ax = plt.subplots()
    plt.plot(t,h, label='elevation')
    plt.xlabel('t / s')
    plt.ylabel('h / m')
    ax.yaxis.set_minor_locator(MultipleLocator(0.2))
    plt.grid(True, which='minor')
    plt.show()

if os.fork():
    # parent
    pass
else:
    # child
    detach_display()