#!/usr/bin/env python
# Wenchang Yang (wenchang@princeton.edu)
# Tue Apr 28 15:15:46 EDT 2020
if __name__ == '__main__':
    from misc.timer import Timer
    wyt = Timer(f'start {__file__}')
import sys, os.path, os, glob
import xarray as xr, numpy as np, pandas as pd
#import matplotlib.pyplot as plt
#more imports
#
if __name__ == '__main__':
    wyt.check('end import')
    
#start from here
'''
data_name = 'precip'
ifiles = [f'tmp/chirps.precip.daily.Japan.subregion.{year:04d}.nc'
    for year in range(2013, 2020)
    ]
ofile_nc = 'chirps.precip.daily.Japan.subregion.2013-2019.nc'
ofile_csv = ofile_nc.replace('.nc', '.csv')

data_name = 'q2m'
trange = pd.date_range('2013-01', '2020-02', freq='MS')
ifiles = [f'tmp/era5.q2m.daily.Japan.subregion.{year:04d}-{month:02d}.nc'
    for year,month in zip(trange.year, trange.month)
    ]
ofile_nc = 'era5.q2m.daily.Japan.subregion.201301-202002.nc'
ofile_csv = ofile_nc.replace('.nc', '.csv')
'''
data_name = 't2m'
trange = pd.date_range('2013-01', '2020-02', freq='MS')
ifiles = [f'tmp/era5.t2m.daily.Japan.subregion.{year:04d}-{month:02d}.nc'
    for year,month in zip(trange.year, trange.month)
    ]
ofile_nc = 'era5.t2m.daily.Japan.subregion.201301-202002.nc'
ofile_csv = ofile_nc.replace('.nc', '.csv')

if data_name in ('t2m',):
    func = lambda x: (x-273.15).assign_attrs(units='degC')
else:
    func = lambda x: x
ds = xr.open_mfdataset(ifiles, combine='by_coords').load()
ds[data_name] = ds[data_name].pipe(func)
ds.to_netcdf(ofile_nc)
print('[saved]:', ofile_nc)
ds[data_name].to_pandas().to_csv(ofile_csv)
print('[saved]:', ofile_csv)
 
if __name__ == '__main__':
    wyt.check(f'end {__file__}')