Edge map order is wrong

[mpadge]

The neighbourhoods package needs to uncontract edges, for which it uses the cached edge maps. The order of these is, however, all mucked up, and so can't be used in current form to directly uncontract the edges:

library (dodgr)
f <- "/<path>/<to>/bristol-sc.Rds"
net <- readRDS (f) |>
    weight_streetnet (wt_profile = "motorcar")
#> Loading required namespace: geodist
#> Loading required namespace: dplyr
netc <- dodgr_contract_graph (net)

h <- attr (netc, "hashc")
f <- list.files (tempdir (), full.names = TRUE,
                 pattern = paste0 ("edge\\_map\\_", h))
edge_map <- readRDS (f)

# group by number of edges, and choose largest contracted edge:
n <- dplyr::group_by (edge_map, edge_new) |>
    dplyr::summarise (n = dplyr::n ()) |>
    dplyr::arrange (by = dplyr::desc (n))
edge_old <- edge_map$edge_old [which (edge_map$edge_new == n$edge_new [1])]
g <- net [match (edge_old, net$edge_), ]
plot (g$.vx0_x, g$.vx0_y, type = "l")

^{Created on 2021-11-26 by the reprex package (v2.0.1.9000)}

[mpadge]

The above commit just changed the old_edges from a std::set to a std::vector, so they are retained in the order in which they are input.

library (dodgr)
packageVersion ("dodgr")
#> [1] '0.2.12.22'
f <- "/<path>/<to>/bristol-sc.Rds"
net <- readRDS (f) |>
    weight_streetnet (wt_profile = "motorcar")
#> Loading required namespace: geodist
#> Loading required namespace: dplyr
netc <- dodgr_contract_graph (net)

h <- attr (netc, "hashc")
f <- list.files (tempdir (), full.names = TRUE,
                 pattern = paste0 ("edge\\_map\\_", h))
edge_map <- readRDS (f)
n <- dplyr::group_by (edge_map, edge_new) |>
    dplyr::summarise (n = dplyr::n ()) |>
    dplyr::arrange (by = dplyr::desc (n))
edge_old <- edge_map$edge_old [which (edge_map$edge_new == n$edge_new [1])]
g <- net [match (edge_old, net$edge_), ]
plot (g$.vx0_x, g$.vx0_y, type = "l")

^{Created on 2021-11-26 by the reprex package (v2.0.1.9000)}

[mpadge]

Re-opening because the result is not quite what it should be:

library (dodgr)
packageVersion ("dodgr")
#> [1] '0.2.12.22'
f <- "/data/mega/code/repos/atfutures-labs/neighbourhoods/bristol-sc.Rds"
net <- readRDS (f) |>
    weight_streetnet (wt_profile = "motorcar")
#> Loading required namespace: geodist
#> Loading required namespace: dplyr
netc <- dodgr_contract_graph (net)
h <- attr (netc, "hashc")
f <- list.files (tempdir (), full.names = TRUE,
                 pattern = paste0 ("edge\\_map\\_", h))
edge_map <- readRDS (f)
n <- dplyr::group_by (edge_map, edge_new) |>
    dplyr::summarise (n = dplyr::n ()) |>
    dplyr::arrange (by = dplyr::desc (n))
edge_old <- edge_map$edge_old [which (edge_map$edge_new == n$edge_new [1])]
g <- net [match (edge_old, net$edge_), ]
par (mfrow = c (1, 2))
plot (g$.vx0_x, g$.vx0_y, type = "l")

obj <- unique (net$object_ [match (g$edge_, net$edge_)])
g2 <- net [which (net$object_ %in% obj), ]
plot (g2$.vx0_x, g2$.vx0_y, type = "l")

^{Created on 2021-11-26 by the reprex package (v2.0.1.9000)}

The re-constructed edges still have a couple of glitches in them.

[mpadge]

All good now:

library (dodgr)
packageVersion ("dodgr")
#> [1] '0.2.12.24'
f <- "/<path>/<to>/bristol-sc.Rds"
graph <- x <- readRDS (f) |>
    weight_streetnet (wt_profile = "motorcar")
#> Loading required namespace: geodist
#> Loading required namespace: dplyr
v <- dodgr_vertices (graph)
verts <- NULL
graph_contracted <- dodgr_contract_graph_internal (graph, v, verts)
edge_map <- graph_contracted$edge_map
n <- dplyr::group_by (edge_map, edge_new) |>
    dplyr::summarise (n = dplyr::n ()) |>
    dplyr::arrange (by = dplyr::desc (n))
edge_old <- edge_map$edge_old [which (edge_map$edge_new == n$edge_new [1])]
g <- graph [match (edge_old, graph$edge_), ]
par (mfrow = c (1, 2))
plot (g$.vx0_x, g$.vx0_y, type = "l")

obj <- unique (graph$object_ [match (g$edge_, graph$edge_)])
g2 <- graph [which (graph$object_ %in% obj), ]
plot (g2$.vx0_x, g2$.vx0_y, type = "l")

^{Created on 2021-11-29 by the reprex package (v2.0.1.9000)}