def smooth(self, hpxmap, badval=hp.UNSEEN, sigma=None):
""" Smooth a healpix map """
healpix.check_hpxmap(hpxmap, None, None)
hpxmap = healpix.masked_array(hpxmap, badval)
hpxmap.fill_value = np.ma.median(hpxmap)
smooth = hp.smoothing(hpxmap, sigma=np.radians(sigma), verbose=False)
return np.ma.array(smooth, mask=hpxmap.mask)
def draw_hpxmap(self,
hpxmap,
pixel=None,
nside=None,
xsize=800,
lonra=None,
latra=None,
badval=hp.UNSEEN,
smooth=None,
**kwargs):
"""
Use pcolor/pcolormesh to draw healpix map.
Parameters:
-----------
hpxmap: input healpix map
pixel: explicit pixel indices (required for partial maps)
nside: explicit nside of the map (required for partial maps)
xsize: resolution of the output image
lonra: longitude range [-180,180] (deg)
latra: latitude range [-90,90] (deg)
badval: set of values considered "bad"
smooth: gaussian smoothing kernel (deg)
Returns:
--------
im,lon,lat,values : mpl image with pixel longitude, latitude (deg), and values
"""
healpix.check_hpxmap(hpxmap, pixel, nside)
hpxmap = healpix.masked_array(hpxmap, badval)
if smooth:
# To smooth we need the full map
hpxmap = healpix.create_map(hpxmap, pixel, nside, badval)
pixel, nside = None, None
hpxmap = healpix.masked_array(hpxmap, badval)
hpxmap = self.smooth(hpxmap, sigma=smooth)
#if pixel is None:
# nside = hp.get_nside(hpxmap.data)
# pixel = np.arange(len(hpxmap),dtype=int)
#elif nside is None:
# msg = "'nside' must be specified for explicit maps"
# raise Exception(msg)
vmin, vmax = np.percentile(hpxmap.compressed(), [2.5, 97.5])
defaults = dict(latlon=True, rasterized=True, vmin=vmin, vmax=vmax)
setdefaults(kwargs, defaults)
lon, lat, values = healpix.hpx2xy(hpxmap,
pixel=pixel,
nside=nside,
xsize=xsize,
lonra=lonra,
latra=latra)
# pcolormesh doesn't work in Ortho...
if self.projection == 'ortho':
im = self.pcolor(lon, lat, values, **kwargs)
else:
# Why were we plotting the values.data?
#im = self.pcolormesh(lon,lat,values.data,**kwargs)
# pcolormesh recommends that values be larger than x,y
# but basemap has problems with this (sometimes?)
# https://github.com/matplotlib/basemap/issues/182
try:
im = self.pcolormesh(lon, lat, values, **kwargs)
except IndexError:
im = self.pcolormesh(lon[:-1, :-1], lat[:-1, :-1], values,
**kwargs)
return im, lon, lat, values