import pandas as pd

import numpy as np

import pyet as pyet

def calc_pet_oudin(tas_control):

pet_control = np.zeros_like((tas_control.values))

time_pd = pd.to_datetime(tas_control.time.values)

for i_lat in range(tas_control.shape[1]):

print(i_lat)

for j_lon in range(tas_control.shape[2]):

df = pd.DataFrame({'YYYYMMDD':time_pd, 'data':tas_control.values[:,i_lat,j_lon]-273.15})

df.set_index('YYYYMMDD', inplace=True)

et_oudin = pyet.oudin(df['data'], lat=np.radians(tas_control.lat.values[i_lat])).values

pet_control[:,i_lat,j_lon]= et_oudin

return pet_control

months = [6,7,8,9]

tas_control = ds_piClim_control_MPIESM_r1i1p1f1_tas.tas.sel(time=ds_piClim_aer_MPIESM_r1i1p1f1_hfss.time.dt.month.isin(months))

pet_control = np.zeros_like((tas_control.values))

time_pd = pd.to_datetime(tas_control.time.values)

for i_lat in range(tas_control.shape[1]):

print(i_lat)

for j_lon in range(tas_control.shape[2]):

df = pd.DataFrame({'YYYYMMDD':time_pd, 'data':tas_control.values[:,i_lat,j_lon]-273.15})

df.set_index('YYYYMMDD', inplace=True)

et_oudin = pyet.oudin(df['data'], lat=np.radians(tas_control.lat.values[i_lat])).values

pet_control[:,i_lat,j_lon]= et_oudin