This function fills missing spatial regions in similarity network matrices with zeros. It ensures that all matrices in the list have the same set of spatial regions.
Value
A list of similarity network matrices with missing spatial regions filled in with zero values.
Details
The function first identifies all unique spatial regions across the input list of matrices. It then ensures that each matrix has the same set of regions by adding missing regions with zero similarity values. This step is crucial for downstream analyses that require consistent dimensions across samples.