#!/usr/bin/env python
# Wenchang Yang (wenchang@princeton.edu)
# Mon Mar  2 17:15:22 EST 2020
import sys, os.path, os, datetime
import xarray as xr, numpy as np, pandas as pd
#import matplotlib.pyplot as plt
#print()

model = 'ERA5'
data_name = 'Vshear'
years = range(1979, 2019)
ofile = f'data.{data_name}.{model}.nc'
if os.path.exists(ofile):
    print('[exists]:', ofile)
    sys.exit()
ifiles = [f'/tigress/wenchang/data/{model.lower()}/analysis_wy/TCI/{model.lower()}.monthly.{year:04d}.Vshear.nc'
    for year in years]
 
if __name__ == '__main__':
    tformat = '%Y-%m-%d %H:%M:%S'
    t0 = datetime.datetime.now()
    print('[start]:', t0.strftime(tformat))
    
    ds = xr.open_mfdataset(ifiles)
    ds = ds.rename(longitude='lon', latitude='lat')
    ds.attrs['model'] = model
    ds.load()

    encoding = {data_name: {'dtype': 'float32', 'zlib': True, 'complevel': 1}}
    ds.to_netcdf(ofile, encoding=encoding)
    print('[saved]:', ofile)

    t1 = datetime.datetime.now()
    print('[total time used]:', f'{(t1-t0).seconds:,} seconds')
    print('[end]:', t1.strftime(tformat))
    print()