<> Expression of a curve or line between two endpoints. <> ・abs(x)　 return absolute value of x. ・sin(rad)　 unit of argument is radian, not degree. ・cos(rad) ・tan(rad) <> ・pi - 3.14159.... ・rnd - random real number [0,1]. ・xf - linear function, 0.0 on left endpoint and 1.0 on right endpoint. ・x - value of x. ・x1 - x (tick) of left endpoint. ・x2 - x (tick) of right endpoint. ・y1 - y of left endpoint. ・y2 - y of right endpoint. ・res - resolution (tick per crotchet). <> A line from left endpoint from right endpoint is given by next expression: y1 * (1 - xf) + y2 * xf In this expression, xf varies with distance from left endpoint, from 0.0 to 1.0.