superbit-collaboration / superbit-metacal

Contains a collection of routines used to perform gmix/metacalibration on simulated SuperBIT images
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Response-weighted shape column confusion (full inv matrix vs. diagonals) #100

Open sweverett opened 2 years ago

sweverett commented 2 years ago

In the current metacalibration/ngmix_fit_superbit3.py implementation, we are computing both the full R_gamma matrix and it's inverse for the g{i}_MC = R_gamma^-1 * g{i}_noshear column here. Importantly this does not include the selection component and is unused as far as I can tell.

Just a few lines later, the actual mcal response-weighted shape estimate g_Rinv is computed using the simpler g{i}_Rinv = g{i}_noshear / (R{ii}_gamma + R{ii}_S). If we're already spending the cycles to compute the actual R_inv for the gamma component, why not just do this for the full responsivity matrix and store that instead?