double sin_data[30] = { 
    0.2078, 0.4065,0.5875,0.7429, 0.8658,  0.9509, 0.9944, 0.9946,  0.9514,  0.8666, 0.7439 ,
	0.5888, 0.4080,0.2094,0.0016,-0.2062,-0.4051, 0.5862, -0.7418,-0.8650, -0.9504, -0.9943,
	-0.9948, -0.9518,-0.8673, -0.7450 ,   -0.5901 ,  -0.4095 , -0.2109 , -0.0032
};