Function logos_gda_program 

pub fn logos_gda_program(rows: usize, cols: usize) -> String

Gaussian discriminant analysis’s covariance in LOGOS over rows samples of cols features — the data filled as Spatial’s GDA app fills it (x row-major i % 256, y i % 256, both means i % 2), each row centred on the mean its label picks and added to sigma as a rank-1 update. It shows Σ (t + 1)·sigma[t], a checksum a transposed or partial covariance does not reproduce.