Shiny, Event reactive, running several functions - r

Question

I am new in shiny, at the moment I am trying to set up a code where I can calculate activity clusters (through DBSCAN package) based on input variables: "eps" (minimum distances between points to be part of a cluster), "minpts" (minimum number of points to certain categories as Health), "maxpts" (minimum number of points for general categories as pubs, restaurants etc).
I did a test only through leaflet (without shiny) and the code runs smoothly, but once I bring-in shiny, I'm not able to make it work
the idea is that the user can modify these 3 variables on the side panel, and click an action button in order to trigger the calculation.
#----------LIBRARIES----------#
library(plyr)
library(geosphere)
library(dbscan)
library(osmdata)
library(sf)
library(tidyr)
library(sp)
library(rgdal)
library(leaflet)
library(shiny)
#-------LOAD FILES-------#
OSM_merged <- read.csv(file = "C:\\Users\\jsainz\\Documents\\R\\Shiny_test\\OSM_merged.csv")
OSM_points <- OSM_merged
OSM_points$color <- OSM_points$category
OSM_points$color <- str_replace_all(OSM_points$color, "Culture", "#3073A")
OSM_points$color <- str_replace_all(OSM_points$color, "Educational", "# 887CAF")
OSM_points$color <- str_replace_all(OSM_points$color,"Financial", "#540002")
OSM_points$color <- str_replace_all(OSM_points$color,"Health", "#D6E899")
OSM_points$color <- str_replace_all(OSM_points$color,"Leisure", "#D2D68D")
OSM_points$color <- str_replace_all(OSM_points$color,"Office", "#D3696C")
OSM_points$color <- str_replace_all(OSM_points$color,"Shop", "#AA9739")
OSM_points$color <- str_replace_all(OSM_points$color,"Sport", "#378B2E")
OSM_points$color <- str_replace_all(OSM_points$color,"Sustain", "#554600")
OSM_points$color <- str_replace_all(OSM_points$color,"Toursim", "#5FAE57")
xy <- OSM_points[,c(2,3)]
OSM_points <- SpatialPointsDataFrame(coords = xy, data = OSM_points,proj4string = CRS("+proj=longlat +datum=WGS84 +ellps=WGS84 +towgs84=0,0,0"))
#-------FUNCTIONS-------#
assign_clusters <- function(poi_df, minPts = NA) {
if(is.na(minPts)) {
if(poi_df[1, "category"] %in% c("Culture", "Leisure", "Education", "Health", "Financial")) {
minPts <- "minpts"
} else minPts <- "maxpts"
}
eps <- "epsilon"
poi_df[c("lng", "lat")] %>%
distm(fun = distHaversine) %>%
as.dist() %>%
dbscan(eps = eps, minPts = minPts) %>%
.[["cluster"]] %>%
cbind(poi_df, cluster = .)
}
get_hull<- function(df) {
cbind(df$lng, df$lat) %>%
as.matrix() %>%
st_multipoint() %>%
st_convex_hull() %>%
st_sfc(crs = 4326) %>%
{st_sf(category = df$category[1], cluster = df$cluster[1], geom = .)}
}
hulls <- function(df) {
df %>%
split(.$cluster) %>%
map(get_hull)
}
#----------SHINY CODE----------#
ui <- fluidPage(
titlePanel("Jorge_Test"),
sidebarPanel(
numericInput(inputId = "epsilon", label = "distance in meters to calculate activity clusters", 200),
numericInput(inputId = "minpts", label = "minimum points to calculate clusters", 5),
numericInput(inputId = "maxpts", label = "maximum points to calculate clusters", 10),
actionButton("run", "Run Calculation"),
actionButton("view", "generate plan"),
width = 2),
mainPanel(
leafletOutput("mymap", width = 1550, height = 850)
)
)
server <- function(input, output, session) {
output$mymap <- renderLeaflet({
leaflet("mymap")%>%
setView(lng = 0.0982, lat = 51.7674, zoom = 15)%>%
addProviderTiles(providers$CartoDB.Positron, options = providerTileOptions(noWrap = TRUE))%>%
addCircleMarkers(data = OSM_points,
radius = .7,
popup = ~category,
color = ~color)})
oberveEvent(input$run, {
updateNumericInput(session, "epsilon")
updateNumericInput(session, "minpts")
updateNumericInput(session, "maxpts")
})
Clean_data <- OSM_merged %>%
split(OSM_merged$category) %>%
map_df(assign_clusters)
hulls_cat <- Clean_data %>%
group_by(category) %>%
summarise()
map_cluster_hulls <- Clean_data %>%
filter(cluster != 0) %>%
select(lng, lat, category, cluster) %>%
split(.$category) %>%
map(hulls)
mdata <- melt(map_cluster_hulls, id = c("category", "cluster", "geom"))
mch <- data.frame(mdata$category, mdata$cluster, mdata$geom)
observeEvent(input$view, {
leafletProxy("mymap", session) %>%
addPolygons(data = mch$geom,
fill = NA,
fillOpacity = .01,
weight = 2,
color = "red",
opacity = .8)
}
)
}
shinyApp(ui, server)
any idea of how to solve it?
here is a link to the OSM_merged.csv file:
https://www.dropbox.com/s/5ok9frcvx8oj16y/OSM_merged.csv?dl=0