def __init__(self, nrho, rss, gong_map=sunpy.map.Map(get_gong_map())):
self._nrho = nrho
self._rss = rss
self.gong_map = gong_map
self.input = pfsspy.Input(self.gong_map, self.nrho, self.rss)
self._output = pfsspy.pfss(self.input)
self.tracer = tracing.PythonTracer()
# First, import required modules import astropy.constants as const import astropy.units as u import matplotlib.pyplot as plt import numpy as np import sunpy.map from astropy.coordinates import SkyCoord import pfsspy from pfsspy import coords, tracing from pfsspy.sample_data import get_gong_map ############################################################################### # Load a GONG magnetic field map. If 'gong.fits' is present in the current # directory, just use that, otherwise download a sample GONG map. gong_fname = get_gong_map() ############################################################################### # We can now use SunPy to load the GONG fits file, and extract the magnetic # field data. # # The mean is subtracted to enforce div(B) = 0 on the solar surface: n.b. it is # not obvious this is the correct way to do this, so use the following lines # at your own risk! gong_map = sunpy.map.Map(gong_fname) # Remove the mean gong_map = sunpy.map.Map(gong_map.data - np.mean(gong_map.data), gong_map.meta) ############################################################################### # The PFSS solution is calculated on a regular 3D grid in (phi, s, rho), where # rho = ln(r), and r is the standard spherical radial coordinate. We need to