data/curves_to_db/example.R

   1 require(RPostgreSQL)
   2
   3 ##############################
   4 # Follow steps in README first
   5 ##############################
   6
   7 nb_curves_per_request <- 100 #curves per (select) request
   8
   9 # Init connection with DB
  10 driver <- PostgreSQL(fetch.default.rec = nb_curves_per_request)
  11 con <- dbConnect(driver, user="irsdi", password="irsdi2017",
  12     host="localhost", port="5432", dbname="edf25m")
  13
  14 # Fill associative array, map index to identifier
  15 indexToID_inDB <- as.character(
  16     dbGetQuery(con, 'SELECT DISTINCT id FROM series')[,"id"] )
  17
  18 # Function to retrieve curves within some indices range
  19 getCurves <- function(indices)
  20 {
  21     indices = indices[ indices <= length(indexToID_inDB) ]
  22     if (length(indices) == 0)
  23         return (NULL)
  24     request <- "SELECT curve FROM series WHERE id in ("
  25     for (i in seq_along(indices))
  26     {
  27         request <- paste(request, indexToID_inDB[ indices[i] ],  sep="")
  28         if (i < length(indices))
  29             request <- paste(request, ",", sep="")
  30     }
  31     request <- paste(request, ")", sep="")
  32     df_series <- dbGetQuery(con, request)
  33
  34 #weird result: an integer, and then string "{val1,val2,val3,...,valD}" :/
  35 #print(summary(df_series))
  36 df_series
  37 #   matrix(df_series[,"value"], ncol=length(indices))
  38 }
  39
  40 # Test
  41 #curves <- getCurves(c(1:3,7,11))
  42 library(epclust)
  43 res <- claws(getCurves, 50, 15, 500, 500, random=FALSE, ncores_clust=3, verbose=TRUE)
  44
  45 dbDisconnect(con)
  46 unlink(temp_file)