Understanding affineUpgrade.m

[aseshasa]

I am trying to understand the function affineUpgrade.m by reading the related paper: Globally Optimal Algorithms for Stratified Autocalibration. I am having trouble with the lines 350-372. The paper does not create cases for the variable y in the appendix. However, you have created such cases and called functions (lines 294-346) that use formulations that do not appear in the paper. Would you please help me understand why this is done?