; X_1 Y_2 Z_3 =
; c_2 c_3 				- c_2 s_3 		 	 s_2 \\
; c_1 s_3 + c_3 s_1 s_2 		c_1 c_3 - s_1 s_2 s_3 		 - c_2 s_1 \\
; s_1 s_3 - c_1 c_3 s_2 		c_3 s_1 + c_1 s_2 s_3 		 c_1 c_2 \\


;mat3x3:
;        mat[0]= cos(y)cos(z) = 1/2 (cos(y-z)+cos(y+z))
;        mat[1]= -cos(y)sin(z) = 1/2 (sin(y-z)-sin(y+z))
;        mat[2]= sin(y)
;
;        mat[3]= sin(x)sin(y)cos(z)+cos(x)sin(z)
;=1/4 (cos(x-y-z)-cos(x+y-z)+cos(x-y+z)-cos(x+y+z)-2 sin(x-z)+2 sin(x+z))
;
;        mat[4]=cos(x)cos(z)-sin(x)sin(y)sin(z)
;=1/4 (2cos(x+z)+2cos(x-z)-sin(x-y+z)+sin(x-y-z)-sin(x+y+z)+sin(x+y-z))
;
;        mat[5]= -sin(x)cos(y) = 1/2 (-sin(x-y)-sin(x+y))
;
;        mat[6]=sin(x)sin(z)-cos(x)cos(z)sin(y)
;=1/4 (2 cos(x-z)-2cos(x+z) -sin(x+y+z)+sin(x-y+z)-sin(x+y-z)+sin(x-y-z))
;
;        mat[7]=cos(z)sin(x)+cos(x)sin(y)sin(z)
;=1/4 (2sin(x+z)+2sin(x-z) +cos(x+y-z)-cos(x+y+z)-cos(x-y-z)+cos(x-y+z))
;        mat[8]=cos(x)cos(y) = 1/2 (cos(x-y)+cos(x+y))