# -*- coding: utf-8 -*-
"""Module for the C/NOFS VEFI instrument.
Supports the Vector Electric Field Instrument (VEFI)
onboard the Communication and Navigation Outage Forecasting
System (C/NOFS) satellite. Downloads data from the
NASA Coordinated Data Analysis Web (CDAWeb).
Description from CDAWeb:
The DC vector magnetometer on the CNOFS spacecraft is a three axis, fluxgate
sensor with active thermal control situated on a 0.6m boom. This magnetometer
measures the Earth's magnetic field using 16 bit A/D converters at 1 sample per
sec with a range of .. 45,000 nT. Its primary objective on the CNOFS
spacecraft is to enable an accurate V x B measurement along the spacecraft
trajectory. In order to provide an in-flight calibration of the magnetic field
data, we compare the most recent POMME model (the POtsdam Magnetic Model of the
Earth, http://geomag.org/models/pomme5.html) with the actual magnetometer
measurements to help determine a set of calibration parameters for the gains,
offsets, and non-orthogonality matrix of the sensor axes. The calibrated
magnetic field measurements are provided in the data file here. The VEFI
magnetic field data file currently contains the following variables:
B_north Magnetic field in the north direction
B_up Magnetic field in the up direction
B_west Magnetic field in the west direction
The data is PRELIMINARY, and as such, is intended for BROWSE PURPOSES ONLY.
References
----------
A brief discussion of the C/NOFS mission and instruments can be found at
de La Beaujardière, O., et al. (2004), C/NOFS: A mission to forecast
scintillations, J. Atmos. Sol. Terr. Phys., 66, 1573–1591,
doi:10.1016/j.jastp.2004.07.030.
Properties
----------
platform
'cnofs'
name
'vefi'
tag
Select measurement type, one of {'dc_b'}
inst_id
None supported
Note
----
- tag = 'dc_b': 1 second DC magnetometer data
Warnings
--------
- The data is PRELIMINARY, and as such, is intended for BROWSE PURPOSES ONLY.
- Limited cleaning routine.
- Module not written by VEFI team.
"""
import datetime as dt
import functools
import numpy as np
from pysat.instruments.methods import general as mm_gen
from pysat import logger
from pysatNASA.instruments.methods import cdaweb as cdw
from pysatNASA.instruments.methods import cnofs as mm_cnofs
# ----------------------------------------------------------------------------
# Instrument attributes
platform = 'cnofs'
name = 'vefi'
tags = {'dc_b': 'DC Magnetometer data - 1 second'}
inst_ids = {'': ['dc_b']}
# ----------------------------------------------------------------------------
# Instrument test attributes
_test_dates = {'': {'dc_b': dt.datetime(2009, 1, 1)}}
# ----------------------------------------------------------------------------
# Instrument methods
[docs]def init(self):
"""Initialize the Instrument object with instrument specific values.
Runs once upon instantiation.
"""
logger.info(mm_cnofs.ackn_str)
self.acknowledgements = mm_cnofs.ackn_str
self.references = '\n'.join((mm_cnofs.refs['mission'],
mm_cnofs.refs['vefi']))
return
[docs]def clean(self):
"""Clean VEFI data to the specified level.
Note
----
'dusty' or 'clean' removes data when interpolation flag is set to 1
'dirty' is the same as 'none'
"""
if (self.clean_level == 'dusty') | (self.clean_level == 'clean'):
idx, = np.where(self['B_flag'] == 0)
self.data = self[idx, :]
return
# ----------------------------------------------------------------------------
# Instrument functions
#
# Use the default CDAWeb and pysat methods
# Set the list_files routine
fname = ''.join(('cnofs_vefi_bfield_1sec_{year:04d}{month:02d}{day:02d}',
'_v{version:02d}.cdf'))
supported_tags = {'': {'dc_b': fname}}
list_files = functools.partial(mm_gen.list_files,
supported_tags=supported_tags)
# Set the load routine
load = cdw.load
# Set the download routine
basic_tag = {'remote_dir': '/pub/data/cnofs/vefi/bfield_1sec/{year:4d}/',
'fname': fname}
download_tags = {'': {'dc_b': basic_tag}}
download = functools.partial(cdw.download, supported_tags=download_tags)
# Set the list_remote_files routine
list_remote_files = functools.partial(cdw.list_remote_files,
supported_tags=download_tags)