function out=fastreinit(nbx1,nbx2,nbx3,nby1,nby2,nby3,in,niter)

out=in;
tic
for i=1:niter,
	dx=nbdx(nbx1,nbx2,nbx3,out);
	dy=nbdx(nby1,nby2,nby3,out')';
	out=out+.05*sign(out).*(1-sqrt(dx.^2+dy.^2));
end
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