Hello,
Just to check… if I wanted to get a galaxy’s effective radius from sersic_reff_x, sersic_reff_y and sersic_rho
Would I use…
sigmaxy=sersic_rho * sersic_reff_x * sersic_reff_y #sigmaxy is covariance
covmat=np.array([[sersic_reff_x**2, sigmaxy], [sigmaxy, sersic_reff_y**2]])
eigenvalues, eigenvectors = LA.eig(covmat)
reff=np.sqrt(np.max(np.abs(eigenvalues)))#semi-major axis effective radius
?
cheers
John