R/read_TNW.R

In MariekeDirk/WINS50_Lidar: Lidar data analysis for the WINS50 project

#'Read the wind data from TNW
#'@description Function to read the wind speed and direction from the TNW lidar. Data can be
#'downloaded from \url{https://offshorewind.rvo.nl/TNW_WindAndWater}.
#'@param dir directory of the files (allowed to be stored in subfolders).
#'@param h height of the measurement (4m, 30m ,40m ,60m ,80m ,100m ,120m ,140m ,160m ,180m ,200m ,250m).
#'@param what choose between Speed and Direction. Wind speed as sqrt(u^2+v^2).
#'@param stn choose between TNWA and TNWB lidar locations.
#'@author Marieke Dirksen
#' @importFrom rlang .data
#'@export
read_TNW<-function(dir="D:/data/Lidar/TNW",h=60,what="Speed",stn="TNWA"){
  # I<-df[,grep("*_Altitude$*", colnames(df))]
  # heights<-subset(df,select=I)
  # heights<-gather(heights,"h","val")

  h_opt<-c(4,30,40,60,80,100,120,140,160,180,200,250)
  # names(df_height)<-c("nr","height")
  h_exists<-h %in% h_opt
  if(h_exists==FALSE){
    message("Height level not included returning FALSE, try 4,30,40,60,80,100,120,140,160,180,200 or 250")
    return(FALSE)
  }

  lidar_opt<-c("TNWA","TNWB")
  lid_exists<-stn %in% lidar_opt
  if(lid_exists==FALSE){
    message("Lidar station name unknown returning FALSE, try TNWA or TNWB")
    return(FALSE)
  }

  tnw<-list.files(dir,pattern="*WindResourceSpeedDirectionStat_F\\.csv$",
                  recursive = TRUE,full.names = TRUE)
  tnw.I<-tnw[grep(stn,tnw)]

  #One of the csv files contains an extra column "spLatitude deg"
  #Used drop to exclude column so all files have the same structure
  df<-do.call("rbind",lapply(tnw.I,function(x){data.table::fread(x,drop="spLatitude deg")}))
  t.vec<-df$`TIMESTAMP (ISO-8601) UTC`
  t.vec<-gsub("[A-Z]"," ",t.vec)
  t.vec<-as.POSIXct(t.vec,format="%Y-%m-%d %H:%M:%S") #



  if(what=="Speed"){
    I<-df[,grep("^WindSpeed*", colnames(df))]
    u<-subset(df,select=I) #.data$

    heights<-as.numeric(gsub("[^0-9.-]", "", names(u)))

    I.h<-which(heights==h)
    if(length(I.h)==1){
      hg<-subset(u,select=I.h)
      df_h<-cbind(t.vec,hg)
      df_h$h<-h
      names(df_h)<-c("time","u","h")
      df_h$u<-as.numeric(df_h$u)
    }

    if(length(I.h)==2){
      message("Two columns with this height level, omitting the non-configurable reference height")
      I.ref<-grep(".*refh.*",colnames(u)[I.h])
      hg<-subset(u,select=I.h)
      hg<-subset(hg,select=-I.ref)
      df_h<-cbind(t.vec,hg)
      df_h$h<-h
      names(df_h)<-c("time","u","h")
    }
    df_h<-df_h[stats::complete.cases(df_h),]
    return(df_h)
  }

  if(what=="Direction"){
    I<-df[,grep("*WindDir*", colnames(df))]
    u<-subset(df,select=I) #.data$

    heights<-as.numeric(gsub("[^0-9.-]", "", names(u)))

    I.h<-which(heights==h)
    if(length(I.h)==1){
      hg<-subset(u,select=I.h)
      df_h<-cbind(t.vec,hg)
      df_h$h<-h
      names(df_h)<-c("time","dir","h")
      df_h$dir<-as.numeric(df_h$dir)
    }

    if(length(I.h)==2){
      message("Two columns with this height level, omitting the non-configurable reference height")
      I.ref<-grep(".*refh.*",colnames(u)[I.h])
      hg<-subset(u,select=I.h)
      hg<-subset(hg,select=-I.ref)
      df_h<-cbind(t.vec,hg)
      df_h$h<-h
      names(df_h)<-c("time","u","h")
    }
    df_h<-df_h[stats::complete.cases(df_h),]
    return(df_h)

  }
}