A Bug!!!

When I use the PtTrend, I got quite different figure when I choose
Pt_GRID_LEFT_TO_RIGHT and Pt_GRID_RIGHT_TO_LEFT while the one from left to
right is absolutely wrong even it’s the same array I used. Finally, the
answer proved to be that the Pt_ARG_TREND_MAX and Pt_ARG_TREND_MIN must be
symeric. It wont’ work even if you set one as 250 while the other is -249.

Nothing but a BUG!
Center of Prototype