#!/usr/bin/python3
# ==================================================================
# display the angle between the Y axes and another vector
# (used to test/understand the meaning of the angle)
# ===================================================================

import numpy as np
import user_interface as ui

from two_vector_angle import two_vector_angle


v1 = [0.0,10.0]                # Y axis

while(True):

    # ---- get and verify the users input

    print()
    s = ui.get_user_input('Enter test angle (degrees): ')

    if not s:
        break

    tf,f = ui.is_float(s)
    if not tf:
        print()
        print(f'input error ({s})')
        continue

    # ---- convert the test angle to a test vector

    r = np.deg2rad(f) 

    v2 = [10.0 * np.cos(r), 10.0 * np.sin(r)]

    # ---- calculate the angle between the
    # ---- Y axes and a test vector

    a_rad = two_vector_angle(v1,v2,True)

    # ---- display the results

    a_deg = np.rad2deg(a_rad)

    print()
    print(f'a_deg = {a_deg}')

print()