x = c(2,3,5,6,3,2,9,5,3,2,1,7,6)
plot(x)
anstieg <- function(zeitreihe){
  # initialisieren
  x = zeitreihe
  lx = length(x)
  sf = numeric(lx)
  ds = numeric(lx)
  i=0
  # Schleife durch die Zeitreihe
  for(xi in x){
    i=i+1
    if(i==1){
    } else{
      if(x[i]>x[i-1]){
        sf[i] = 1
        ds[i] = ds[i-1] + 1
      } else{
        sf[i] = 0
        ds[i] = 0
      }
    }
  }
  dfx = data.frame(x,sf,ds)  
  return(dfx)
}