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bsplinecurve bscurv  3 2  -1.0 4   1.0 4  0 0 0 1   1 0 0 1   2 0 0 1   3 0 0 1
incdeg bscurv 10
translate bscurv 0 -4 0
set i 1
repeat 100 {cmovepoint bscurv 0.3 0. 0.05 0.0e0 ; incr i 1; repaint}
set i 1
repeat 100 {cmovepoint bscurv 0.3 0. -0.05 0.0e0 ; incr i 1;repaint}
renamevar bscurv result
set length 2.9999999999999996

