#  -*- coding=utf-8 -*-
import math
import numpy as np

# 欧拉角转四元数
while(1):
    which_mode = input("欧拉角转四元数输入1，四元数转欧拉角输入2。
请输入:")
    if(which_mode == "1"):
        print("
源坐标系到目标坐标系旋转顺序为X,Y,Z,左手系.")
        r = float(input("绕x轴旋转角度:"))
        p = float(input("绕y轴旋转角度:"))
        y = float(input("绕z轴旋转角度:"))

        sinp = math.sin(math.radians(p/2))
        siny = math.sin(math.radians(y/2))
        sinr = math.sin(math.radians(r/2))

        cosp = math.cos(math.radians(p/2))
        cosy = math.cos(math.radians(y/2))
        cosr = math.cos(math.radians(r/2))

        w = cosr*cosp*cosy + sinr*sinp*siny
        x = sinr*cosp*cosy - cosr*sinp*siny
        y = cosr*sinp*cosy + sinr*cosp*siny
        z = cosr*cosp*siny - sinr*sinp*cosy

        print("x : {}".format(x))
        print("y : {}".format(y))
        print("z : {}".format(z))
        print("w : {}".format(w))
    elif(which_mode == "2"):
        print("请按顺序输入4元数")
        x = input("x:")
        y = input("y:")
        z = input("z:")
        w = input("w:")
        
        x = float(x)
        y = float(y)
        z = float(z)
        w = float(w)

        r = math.atan2(2 * (w * x + y * z), 1 - 2 * (x * x + y * y))
        r = r / math.pi * 180
        p = math.asin(2 * (w * y - z * x))
        p = p / math.pi * 180
        y = math.atan2(2 * (w * z + x * y), 1 - 2 * (y * y + z * z))
        y = y / math.pi * 180
        print("
源坐标系到目标坐标系旋转顺序为X,Y,Z,左手系．")
        print("绕x轴旋转角度: {}".format(r))
        print("绕y轴旋转角度: {}".format(p))
        print("绕z轴旋转角度: {}
".format(y))

PLUS

scipy库里自带的函数 四元数 -> 欧拉角 欧拉角->四元数 欧拉角->旋转矩阵 原坐标系到目标坐标系 , 右手系, 内旋（绕固定轴）

from scipy.spatial.transform import Rotation as R

def quaternion2euler(quaternion):
    r = R.from_quat(quaternion)
    euler = r.as_euler(xyz, degrees=True)
    return euler

def euler2quaternion(euler):
    r = R.from_euler(xyz, euler, degrees=True)
    quaternion = r.as_quat()
    return quaternion

def euler2rotation(euler):
    r = R.from_euler(xyz, euler, degrees=True)
    rotation_matrix = r.as_dcm()
    return rotation_matrix