# download.file("https://kaggle2.blob.core.windows.net/competitions-data/kaggle/5229/train.zip?sv=2012-02-12&se=2016-05-23T09%3A18%3A48Z&sr=b&sp=r&sig=g5zLGp5a67a54mjd7K43wdjCXp9xoGoOumU1NeEMWUs%3D" , destfile = "testfile )
library(tiff)
library(raster)
library(rgdal)
library(sp)
#setwd("/home/rstudio1/kaggle_satellite/train")
rlist=list.files(getwd(), pattern="tif$", full.names=FALSE)
for(i in rlist) {
  assign(unlist(strsplit(i, "[.]"))[1], raster(i))
  
  } 

rastMeans = sapply(rlist, function(filename) {
  r = raster(filename)
  return(mean(values(r), na.rm=TRUE))
})

rastMin = sapply(rlist, function(filename) {
  r = raster(filename)
  return(min(values(r), na.rm=TRUE))
})

rastMax = sapply(rlist, function(filename) {
  r = raster(filename)
  return(max(values(r), na.rm=TRUE))
})

rastSD = sapply(rlist, function(filename) {
  r = raster(filename)
  return(sd(values(r), na.rm=TRUE))
})

rastmedian = sapply(rlist, function(filename) {
  r = raster(filename)
  return(median(values(r), na.rm=TRUE))
})

rastdata = sapply(rlist, function(filename) {
  r = raster(filename)
  return(as.data.frame(values(r), na.rm=TRUE))
})