@orange Yes I did, but I don't see where this path has been modified, the width is still the one from the panel with no reduction
p1 = gr_peakreduct.createPath([a[0], a[1], a[2], a[3]], [0,1,0,-1], 1.0);[a[0], a[1], a[2], a[3]] this is equivalent to just write a