def read_data(settings, suffix, name, year, grid_lats, grid_lons, period, N_OBS_PER_DAY):
'''
Read in the data from the netCDF files
:param Settings settings: object to hold all filepaths etc.
:param str suffix: used to determine whether using strict or relaxed criteria
:param str name: variable name
:param int year: year to read
:param array grid_lats: latitudes
:param array grid_lons: longitudes
:param str period: which period (day/night/all)
:param int N_OBS_PER_DAY: number of observation times per day
:returns: var_3hrlys - array of 3hrly data for single variable
'''
if suffix == "relax":
N_OBS_OVER_DAYS = 1
N_OBS_OVER_PENTAD = 2
elif suffix == "strict":
N_OBS_OVER_DAYS = 2
N_OBS_OVER_PENTAD = 4
# set up empty data array
var_3hrlys = np.ma.zeros([utils.days_in_year(year)*N_OBS_PER_DAY, len(grid_lats), len(grid_lons)])
var_3hrlys.mask = np.zeros([utils.days_in_year(year)*N_OBS_PER_DAY, len(grid_lats), len(grid_lons)])
var_3hrlys.fill_value = settings.mdi
year_start = dt.datetime(year, 1, 1, 0, 0)
for month in np.arange(12) + 1:
print year, month
month_start = utils.day_of_year(year, month)
month_end = month_start + calendar.monthrange(year, month)[1]
filename = "{}/{}_1x1_3hr_{}{:02d}_{}_{}.nc".format(settings.DATA_LOCATION, settings.OUTROOT, year, month, period, suffix)
ncdf_file = ncdf.Dataset(filename,'r', format='NETCDF4')
if month == 12:
# run to end of year if december
var_3hrlys[month_start*N_OBS_PER_DAY:, :, :] = ncdf_file.variables[name][:]
else:
var_3hrlys[month_start*N_OBS_PER_DAY:month_end*N_OBS_PER_DAY, :, :] = ncdf_file.variables[name][:]
return var_3hrlys # read_data
def do_conversion(start_year=defaults.START_YEAR, end_year=defaults.END_YEAR, period="all", doBC=False, doQC=True):
"""
Convert dailies to pentads 1x1
:param int start_year: start year to process
:param int end_year: end year to process
:param str period: which period to do day/night/all?
:param bool doBC: work on the bias corrected data
:param bool doQC: incorporate the QC flags or not
:returns:
"""
settings = set_paths_and_vars.set(doBC=doBC, doQC=doQC)
OBS_ORDER = utils.make_MetVars(settings.mdi, multiplier=False)
for year in np.arange(start_year, end_year + 1):
# set up empty data array
all_dailies = np.ma.zeros([len(OBS_ORDER), utils.days_in_year(year), len(grid_lats), len(grid_lons)])
all_dailies.mask = np.zeros([len(OBS_ORDER), utils.days_in_year(year), len(grid_lats), len(grid_lons)])
all_dailies.fill_value = settings.mdi
all_n_obs = np.zeros([utils.days_in_year(year), len(grid_lats), len(grid_lons)])
year_start = dt.datetime(year, 1, 1, 0, 0)
for month in np.arange(12) + 1:
print year, month
month_start = utils.day_of_year(year, month)
month_end = month_start + calendar.monthrange(year, month)[1]
filename = "{}/{}_1x1_daily_{}{:02d}_{}.nc".format(
settings.DATA_LOCATION, settings.OUTROOT, year, month, period
)
ncdf_file = ncdf.Dataset(filename, "r", format="NETCDF4")
for v, var in enumerate(OBS_ORDER):
if month == 12:
# run to end of year if december
all_dailies[v, month_start:, :, :] = ncdf_file.variables[var.name][:]
else:
all_dailies[v, month_start:month_end, :, :] = ncdf_file.variables[var.name][:]
# now get number of observations
if month == 12:
all_n_obs[month_start:, :, :] = ncdf_file.variables["n_obs"][:]
else:
all_n_obs[month_start:month_end, :, :] = ncdf_file.variables["n_obs"][:]
if calendar.isleap(year):
assert all_dailies.shape[1] == 366
# extract 6-day pentad
incl_feb29th = all_dailies[:, 55:61, :, :]
# remove the data of Feb 29th from array
# np.ma.delete doesn't exist, so have to copy mask separately
mask = all_dailies.mask
all_dailies = np.delete(all_dailies, 59, 1)
mask = np.delete(mask, 59, 1)
all_dailies = np.ma.array(all_dailies, mask=mask)
del mask
# number of observations
incl_feb29th_n_obs = all_n_obs[55:61, :, :]
all_n_obs = np.delete(all_n_obs, 59, 0)
else:
assert all_dailies.shape[1] == 365
shape = all_dailies.shape
all_dailies = all_dailies.reshape(shape[0], -1, 5, shape[-2], shape[-1])
n_days_per_pentad = np.ma.count(all_dailies, axis=2)
if settings.doMedian:
pentad_grid = utils.bn_median(all_dailies, axis=2)
else:
pentad_grid = np.ma.mean(all_dailies, axis=2)
# clear up memory
del all_dailies
gc.collect()
all_n_obs = all_n_obs.reshape(-1, 5, shape[-2], shape[-1])
all_n_obs = np.sum(all_n_obs, axis=1)
pentad_grid.mask[
n_days_per_pentad < N_OBS
] = True # mask where fewer than 2 days have values # KW THIS IS ACTUALLY 2 - WHICH I THINK IS GOOD
# the pentad containing feb 29th is the 11th in the year
if calendar.isleap(year):
# overwrite this with the me(di)an of a 6-day pentad
if settings.doMedian:
pentad_grid[:, 11, :, :] = utils.bn_median(incl_feb29th, axis=1)
else:
pentad_grid[:, 11, :, :] = np.ma.mean(incl_feb29th, axis=1)
feb_n_days_per_pentad = np.ma.count(incl_feb29th, axis=1)
pentad_grid.mask[:, 11, :, :][feb_n_days_per_pentad < N_OBS] = True
n_days_per_pentad[:, 11, :, :] = feb_n_days_per_pentad
all_n_obs[11, :, :] = np.sum(incl_feb29th_n_obs, axis=0)
print "processed Feb 29th"
times = utils.TimeVar("time", "time since 1/1/{} in hours".format(year), "hours", "time")
times.data = np.arange(0, pentad_grid.shape[1]) * 5 * 24
out_filename = settings.DATA_LOCATION + settings.OUTROOT + "_1x1_pentad_{}_{}.nc".format(year, period)
utils.netcdf_write(
out_filename,
pentad_grid,
n_days_per_pentad[0],
all_n_obs,
OBS_ORDER,
grid_lats,
grid_lons,
times,
frequency="P",
)
del pentad_grid
del all_n_obs
del n_days_per_pentad
gc.collect()
return # do_conversion
