#DATE MODIFIED: 08/12/2014            

### Plotting and computing average MAE per station for different methods

plot_MAE_per_station_fun <- function(list_data_v,names_var,interp_method,var_background,stat_loc,out_suffix){

  #Function to create a series of residuals MAE plots...

  mae_fun<-function(x){mean(abs(x))} #Mean Absolute Error give a residuals vector

  sd_abs_fun<-function(x){sd(abs(x))} #sd Absolute Error give a residuals vector

  ### Start script ###

  data_v_test <- list_data_v[[1]]

  #Convert sp data.frame and combined them in one unique df, see function define earlier

  data_v_combined <-convert_spdf_to_df_from_list(list_data_v) #long rownames

  #names_var_all<-c("res_mod1","res_mod2","res_mod3","res_mod4","res_mod5","res_mod6","res_mod7")#,"res_mod8","res_mod9","res_mod10")

  names_var_all <- res_model_name <- paste("res",names_var,sep="_")

  t<-melt(data_v_combined,

        measure=names_var_all, 

        id=c("id"),

        na.rm=T)

  names(data_v_combined)

  mae_tb<-cast(t,id~variable,mae_fun) #join to station location...

  data_v_mae <-merge(mae_tb,stat_loc,by.x=c("id"),by.y=c("STAT_ID"))

  coords<- data_v_mae[c('longitude','latitude')]              #Define coordinates in a data frame

  CRS_interp<-proj4string(data_v_test)

  coordinates(data_v_mae)<-coords                      #Assign coordinates to the data frame

  proj4string(data_v_mae)<- proj4string(stat_loc)                #Assign coordinates reference system in PROJ4 format

  data_v_mae<-spTransform(data_v_mae,CRS(CRS_interp))     #Project from WGS84 to new coord. system

  list_p_mae <- vector("list", length(names_var_all))

  #names_var <- c("mod1","mod2","mod3","mod7")

  for (k in 1:length(names_var)){

    model_name <- names_var[k]

    res_model_name <- paste("res",model_name,sep="_")

    p1 <- levelplot(var_background,scales = list(draw = FALSE), colorkey = FALSE,par.settings = GrTheme)

    df_tmp=subset(data_v_mae,data_v_mae[[res_model_name]]!="NaN")

    p2 <- bubble(df_tmp,res_model_name, main=paste("Average MAE per station for ",model_name," ",interp_method, sep=""),

               na.rm=TRUE)

    p3 <- p2 + p1 + p2 #to force legend...

    list_p_mae[[k]] <- p3

  }

  data_mae_obj <- list(list_p_mae,data_v_mae)

  names(data_mae_obj) <- c("list_p_mae","data_v_mae")

  return(data_mae_obj)

}