Dear list, I'm trying to fit a nested blockmodel to a (bipartite) network with ~10^6 edges. The algorithm minimize_nested_blockmodel_dl() doesn't terminate; it keeps on adding layers indefinitely until it runs out of memory / hits walltime, see below. What could be going on? Many thanks in advance, Peter level 2 : replaced (94, 1) -> (94, 16) , dS: -15452.0134871 3 l=3 B: 8 <- 16 shrinking 16 -> 11 l=3 B: 8 <- 16 B=11 niter: 1 count: 1 breaks: 1 min_S: 1002.5742 max_S: 1002.5742 S: 1002.5742 ΔS: 0.00000 moves: 0 l=3 B: 8 <- 16 shrinking 11 -> 8 l=3 B: 8 <- 16 B=8 niter: 1 count: 1 breaks: 1 min_S: 838.70438 max_S: 838.70438 S: 838.70438 ΔS: 0.00000 moves: 0 l=3 Current bracket: (2, 8, 16) (691.21840695494018, 838.70438205706921, 1340.6798309766764) l=3 B: 5 <- 8 shrinking 8 -> 5 l=3 B: 5 <- 8 B=5 niter: 1 count: 0 breaks: 0 min_S: 752.39171 max_S: 753.34067 S: 752.39171 ΔS: -0.948956 moves: 2 l=3 B: 5 <- 8 B=5 niter: 2 count: 0 breaks: 0 min_S: 751.86303 max_S: 753.34067 S: 751.86303 ΔS: -0.528683 moves: 1 l=3 B: 5 <- 8 B=5 niter: 3 count: 1 breaks: 1 min_S: 751.86303 max_S: 753.34067 S: 751.86303 ΔS: 0.00000 moves: 0 l=3 Current bracket: (2, 5, 8) (691.21840695494018, 751.86302859686145, 838.70438205706921) l=3 B: 3 <- 5 shrinking 5 -> 3 l=3 B: 3 <- 5 B=3 niter: 1 count: 0 breaks: 0 min_S: 720.12311 max_S: 720.62000 S: 720.12311 ΔS: -0.496886 moves: 1 l=3 B: 3 <- 5 B=3 niter: 2 count: 1 breaks: 1 min_S: 720.12311 max_S: 720.62000 S: 720.12311 ΔS: 0.00000 moves: 0 l=3 Current bracket: (2, 3, 5) (691.21840695494018, 720.123114036723, 751.86302859686145) l=3 Current bracket: (2, 2, 3) (691.21840695494018, 691.21840695494018, 720.123114036723) l=3 Bisect at B = 2 with S = 691.2184069549402 l=3 Best result: B = 2, S = 691.2184069549402 level 3 : replaced (16, 1) -> (16, 2) , dS: -628.252218219 4 l=4 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=4 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=4 Bisect at B = 2 with S = 26.65330734662712 l=4 Best result: B = 2, S = 26.65330734662712 level 4 : replaced (2, 1) -> (2, 2) , dS: -1.86264514923e-09 5 l=5 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=5 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=5 Bisect at B = 2 with S = 26.65330734662712 l=5 Best result: B = 2, S = 26.65330734662712 level 5 : replaced (2, 1) -> (2, 2) , dS: -1.86264514923e-09 6 l=6 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=6 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=6 Bisect at B = 2 with S = 26.65330734662712 l=6 Best result: B = 2, S = 26.65330734662712 level 6 : replaced (2, 1) -> (2, 2) , dS: -1.86264514923e-09 7 l=7 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=7 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=7 Bisect at B = 2 with S = 26.65330734662712 l=7 Best result: B = 2, S = 26.65330734662712 level 7 : replaced (2, 1) -> (2, 2) , dS: -1.86264514923e-09 8 l=8 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=8 Current bracket: (2, 2, 2) (26.653307346627116, 26.653307346627116, 26.653307346627116) l=8 Bisect at B = 2 with S = 26.65330734662712 and l is increasing into the thousands if the left alone.