addModule a siteCoords bt
| nrows <- maximum$ [i | (_,(i,j)) <- siteCoords ]
, sitesByRow <- [ [(s,c) | (s,(r,c)) <- siteCoords, r==i]
addModule a siteCoords bt
| nrows <- maximum$ [i | (_,(i,j)) <- siteCoords ]
, sitesByRow <- [ [(s,c) | (s,(r,c)) <- siteCoords, r==i]