load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"


begin
;;=============================================
;;=========== beginning of settings ===========
;;=============================================
neof = (/0,1/); what pcs to calculate
years = (/1984,2013/)
months= (/7,9/)


diri="."; input directory
; fin="EOF.v.700.nc"; input file
; fin="EOF.v.200.nc"; input file
fin="EOF.Tb.nc"; input file
; varname="vwnd" ; variable name of EOF, for the title
varname="Tb" ; variable name of EOF, for the title
interval=2 ; Tb has 8 times a day and vwnd 4
threshold=0.6; arbitrary, need to discuss


inf=addfile(diri+"/"+fin,"r")
pc_all=inf->eof_ts
time=inf->time
cd=cd_calendar(time,0)
indjas=ind(cd(:,0) .ge. years(0) .and. cd(:,0) .le. years(1) .and. \
           cd(:,1) .ge. months(0).and. cd(:,1) .le. months(1))

pc1=pc_all(0,indjas)
pc2=pc_all(1,indjas)

pc1:=pc1(::interval)
pc2:=pc2(::interval); make the time series having consistent time interval

pc_square=sqrt(pc1^2+pc2^2)

; A simple way to identify AEWs, not perfect, need to discuss
sd=stddev(pc_square)
mean=avg(pc_square)
pc_norm=(pc_square-mean)/sd
copy_VarCoords(pc1,pc_norm)
indaew=ind(pc_norm .ge. threshold)

end