def TaylorFit(block):
    A = []
    b = []
    for s in range(3):
        for x in range(3):
            for y in range(3):
                z = block[s,x,y]
                row = [s*s,x*x,y*y,x*y,s,x,y,1]
                A.append(row)
                b.append([z])
    params,_,_,s = lstsq(A,b)
    return params.flatten()
a*s*s + b*x*x + c*y*y + d*x*y + e*s + f*x + g*y + h
dataset/ETHPy150Open bolme/pyvision/src/pyvision/point/DetectorDOG.py/TaylorFit