Table 1.

Example matrix for gene-expression data

	a	b	c	d
α	22	73	57	17
β	57	32	64	21
γ	41	83	21	23
δ	65	81	59	70
ε	18	79	56	64
ρ	52	39	59	16
π	30	76	61	65

The rows denote different samples or conditions, such as the same cell type in different biological while the columns denote genes. G [γ, c] denotes the quantitative expression of gene c in the situation γ.