# -*- coding: utf-8 -*-
# Copyright (C) 2017 AGB
# Full license can be found in LICENSE.txt
# ---------------------------------------------------------------------------
""" Perform OCB gridding for SuperDARN vorticity data
Notes
-----
Specialised SuperDARN data product, available from: gchi@bas.ac.uk
"""
import datetime as dt
import numpy as np
import ocbpy
import ocbpy.ocb_scaling as ocbscal
[docs]def vort2ascii_ocb(vortfile, outfile, hemisphere=0, ocb=None,
ocbfile='default', instrument='', max_sdiff=600,
save_all=False, min_sectors=7, rcent_dev=8.0, max_r=23.0,
min_r=10.0):
""" Coverts the location of vorticity data from AACGM to OCB coordinates
Parameters
----------
vortfile : str
file containing the required vorticity file sorted by time
outfile : str
filename for the output data
hemisphere : int
Hemisphere to process (can only do one at a time). 1=Northern,
-1=Southern, 0=Determine from data (default=0)
ocb : ocbpy.ocboundary.OCBoundary or NoneType)
Object containing open closed boundary data or None to load from file
ocbfile : str
file containing the required OC boundary data sorted by time, ignorned
if OCBoundary object supplied. (default='default')
instrument : str
Instrument providing the OCBoundaries. Requires 'image' or 'ampere'
if a file is provided. If using filename='default', also accepts
'amp', 'si12', 'si13', 'wic', and ''. (default='')
max_sdiff : int
maximum seconds between OCB and data record in sec (default=600)
save_all : bool
Save all data (True), or only that needed to calcuate OCB and vorticity
(False). (default=False)
min_sectors : int
Minimum number of MLT sectors required for good OCB. (default=7)
rcent_dev : float
Maximum number of degrees between the new centre and the AACGM pole
(default=8.0).
max_r : float
Maximum radius for open-closed field line boundary in degrees.
(default=23.0)
min_r : float
Minimum radius for open-closed field line boundary in degrees
(default=10.0)
Raises
------
IOError
If unable to open input or output file
ValueError
If unable to retrieve all necessary data from the input file
Notes
-----
Input header or col_names must include the names in the default string.
"""
if not ocbpy.instruments.test_file(vortfile):
raise IOError("vorticity file cannot be opened [{:s}]".format(
vortfile))
if not isinstance(outfile, str):
raise IOError("output filename is not a string [{:}]".format(outfile))
# Read the vorticity data
vdata = load_vorticity_ascii_data(vortfile, save_all=save_all)
need_keys = ["VORTICITY", "CENTRE_MLAT", "DATETIME", "MLT"]
if vdata is None or not all([kk in vdata.keys() for kk in need_keys]):
estr = "unable to load necessary data from [{:s}]".format(vortfile)
raise ValueError(estr)
# Load the OCB data
if ocb is None or not isinstance(ocb, ocbpy.ocboundary.OCBoundary):
vstart = vdata['DATETIME'][0] - dt.timedelta(seconds=max_sdiff + 1)
vend = vdata['DATETIME'][-1] + dt.timedelta(seconds=max_sdiff + 1)
# If hemisphere isn't specified, set it here
if hemisphere == 0:
hemisphere = np.sign(np.nanmax(vdata['CENTRE_MLAT']))
# Ensure that all data is in the same hemisphere
if hemisphere == 0:
hemisphere = np.sign(np.nanmin(vdata['CENTRE_MLAT']))
elif hemisphere != np.sign(np.nanmin(vdata['CENTRE_MLAT'])):
raise ValueError("".join(["cannot process observations from ",
"both hemispheres at the same time;",
" set hemisphere=+/-1 to choose."]))
# Initialize the OCBoundary object
ocb = ocbpy.ocboundary.OCBoundary(ocbfile, stime=vstart, etime=vend,
instrument=instrument,
hemisphere=hemisphere)
elif hemisphere == 0:
# If the OCBoundary object is specified and hemisphere isn't use
# the OCBoundary object to specify the hemisphere
hemisphere = ocb.hemisphere
# Test the OCB data
if ocb.filename is None or ocb.records == 0:
ocbpy.logger.error("no data in OCB file [{:}]".format(ocb.filename))
return
# Remove the data from the opposite hemisphere
igood = np.where(np.sign(vdata['CENTRE_MLAT']) == hemisphere)[0]
if igood.shape != vdata['CENTRE_MLAT'].shape:
if len(igood) == 0:
# Exit with warning if no vorticity data from this hemisphere
ocbpy.logger.warning("".join(["No ", "north" if hemisphere == 1
else "south",
"ern hemisphere data in file: [",
vortfile, "]"]))
return
# Downselect vorticity data
for k in vdata.keys():
vdata[k] = vdata[k][igood]
# Set the reference radius
ref_r = 90.0 - abs(ocb.boundary_lat)
# Open the output file for writting
with open(outfile, 'w') as fout:
# Write header line
outline = "#DATE TIME"
if save_all:
vkeys = [kk for kk in vdata.keys() if kk != "DATETIME"]
outline = " ".join([outline, " ".join(vkeys)])
outline = " ".join([outline, "OCB_LAT OCB_MLT NORM_VORT\n"])
fout.write(outline)
# Initialise the ocb and vorticity indices
ivort = 0
num_vort = vdata['DATETIME'].shape[0]
# Cycle through the data, matching vorticity and OCB records
while ivort < num_vort and ocb.rec_ind < ocb.records:
ivort = ocbpy.match_data_ocb(ocb, vdata['DATETIME'], idat=ivort,
max_tol=max_sdiff,
min_sectors=min_sectors,
rcent_dev=rcent_dev, max_r=max_r,
min_r=min_r)
if ivort < num_vort and ocb.rec_ind < ocb.records:
# Use the indexed OCB to convert the AACGM grid coordinate to
# one related to the OCB
nlat, nmlt, ncor = ocb.normal_coord(
vdata['CENTRE_MLAT'][ivort], vdata['MLT'][ivort])
nvort = ocbscal.normal_curl_evar(vdata['VORTICITY'][ivort],
ocb.r[ocb.rec_ind] + ncor,
ref_r)
# Format the output line
# DATE TIME (SAVE_ALL) OCB_LAT OCB_MLT NORM_VORT
outline = "{:} ".format(vdata['DATETIME'][ivort])
if save_all:
for kk in vkeys:
outline += "{:} ".format(vdata[kk][ivort])
outline += "{:.2f} {:.6f} {:.6f}\n".format(nlat, nmlt, nvort)
fout.write(outline)
# Move to next line
ivort += 1
return
[docs]def load_vorticity_ascii_data(vortfile, save_all=False):
"""Load SuperDARN vorticity data files.
Parameters
----------
vortfile : str
SuperDARN vorticity file in block format
save_all : bool
Save all data from the file (True), or only data needed to calculate
the OCB coordinates and normalised vorticity (False). (default=False)
Returns
-------
vdata : dict
Dictionary of numpy arrays
"""
if not ocbpy.instruments.test_file(vortfile):
return None
# Open the data file
with open(vortfile, "r") as fvort:
# Initialise the output dictionary
vkeys = ["YEAR", "MONTH", "DAY", "UTH", "VORTICITY", "MLT",
"CENTRE_MLAT", "DATETIME"]
if save_all:
vkeys.extend(["R1BM1", "R1BM2", "R2BM1", "R2BM2", "AREA",
"CENTRE_GLAT", "CENTRE_GLON", "C1_GLAT", "C1_GLON",
"C2_GLAT", "C2_GLON", "C3_GLAT", "C3_GLON",
"C4_GLAT", "C4_GLON", "CENTRE_MLON", "C1_MLAT",
"C1_MLON", "C2_MLAT", "C2_MLON", "C3_MLAT",
"C3_MLON", "C4_MLAT", "C4_MLON"])
vdata = {vk: list() for vk in vkeys}
vkeys = set(vkeys)
# Set the data block keys
bkeys = [["R1BM1", "R1BM2", "R2BM1", "R2BM2", "AREA", "VORTICITY",
"MLT"],
["GFLG", "CENTRE_GLAT", "CENTRE_GLON", "C1_GLAT", "C1_GLON",
"C2_GLAT", "C2_GLON", "C3_GLAT", "C3_GLON", "C4_GLAT",
"C4_GLON"],
["MFLG", "CENTRE_MLAT", "CENTRE_MLON", "C1_MLAT", "C1_MLON",
"C2_MLAT", "C2_MLON", "C3_MLAT", "C3_MLON", "C4_MLAT",
"C4_MLON"]]
# Read the lines and assign data. Recall that blank lines in file are
# returned as '\n'
vline = fvort.readline()
vsplit = vline.split()
vinc = 0
while len(vline) > 0:
if vinc == 0:
# This is a date line
if len(vsplit) != 4:
estr = "".join(["unexpected line encountered when date ",
"line expected [{:s}]".format(vline)])
ocbpy.logger.error(estr)
fvort.close()
return None
# Save the data in the format desired for the output dict
yy = int(vsplit[0])
mm = int(vsplit[1])
dd = int(vsplit[2])
hh = float(vsplit.pop())
# Calculate and save the datetime
stime = " ".join(vsplit)
dtime = (dt.datetime.strptime(stime, "%Y %m %d")
+ dt.timedelta(seconds=np.floor(hh * 3600.0)))
vinc += 1
elif vinc == 1:
# This is a number of entries line
if len(vsplit) != 1:
estr = "".join(["unexpected line encountered when number",
" of entries line expected ",
"[{:s}]".format(vline)])
ocbpy.logger.error(estr)
fvort.close()
return None
# Save the number of entries
nentries = int(vsplit[0])
vinc += 1
else:
# This is an entry. For each entry there are three lines
ninc = 0
while ninc < nentries:
# Save the time data
vdata['YEAR'].append(yy)
vdata['MONTH'].append(mm)
vdata['DAY'].append(dd)
vdata['UTH'].append(hh)
vdata['DATETIME'].append(dtime)
for bklist in bkeys:
# Test to see that this line has the right number of
# columns
if len(vsplit) != len(bklist):
estr = "".join(["unexpected line encountered ",
"for a data block ",
"[{:s}]".format(vline)])
ocbpy.logger.error(estr)
fvort.close()
return None
# Save all desired keys
gkeys = list(vkeys.intersection(bklist))
for gk in gkeys:
ik = bklist.index(gk)
vdata[gk].append(float(vsplit[ik]))
# Move to next line
vline = fvort.readline()
vsplit = vline.split()
# All data lines for this entry have been processed,
# block line incriment
ninc += 1
# All entries in block have been processed, reset incriment
vinc = 0
# Move to next line
vline = fvort.readline()
vsplit = vline.split()
# Recast lists as numpy arrays
for k in vdata.keys():
vdata[k] = np.array(vdata[k])
return vdata