def adjacency_matrix(tilera, tiledec, fiberposfile=None):
"""Overlap area matrix between slit blocks and radial bins, given
tile ras and decs."""
# compute x & y on each tile to ra & dec
# match ras and decs together at some fiducial size
# (this ignores ellipticity, etc., but the slite blocks are pretty big)
#
if fiberposfile is None:
fiberposfile = os.path.join(os.environ['DESIMODEL'], 'data',
'focalplane', 'fiberpos.fits')
from astropy.io import fits
fpos = fits.getdata(fiberposfile)
# really slow, not vectorized.
pos = [[
focalplane.xy2radec(tra, tdec, fx, fy)
for fx, fy in zip(fpos['x'], fpos['y'])
] for tra, tdec in zip(tilera, tiledec)]
pos = numpy.array(pos)
ras = pos[:, :, 0].ravel()
decs = pos[:, :, 1].ravel()
slitno = numpy.tile(fpos['slitblock'] + fpos['petal'] * 20, len(tilera))
radbin = numpy.floor(numpy.sqrt(fpos['x']**2 + fpos['y']**2) /
20).astype('i4')
radbin = numpy.tile(radbin, len(tilera))
expnum = numpy.repeat(numpy.arange(len(tilera)), len(fpos))
rad = 1.4 / 60
m1, m2, d12 = match_radec(ras, decs, ras, decs, rad, notself=True)
m = expnum[m1] != expnum[m2]
m1 = m1[m]
m2 = m2[m]
d12 = d12[m]
# area of intersection of two equal-size circles?
# area: 2r^2 arccos(d/2r)-0.5 d sqrt((2r-d)(2r+d))
area = (2 * rad**2 * numpy.arccos(d12 / 2. / rad) - 0.5 * d12 * numpy.sqrt(
(2 * rad - d12) * (2 * rad + d12)))
nslitno = numpy.max(slitno) + 1
nradbin = numpy.max(radbin) + 1
adj = numpy.zeros(nslitno**2, dtype='f4')
adjr = numpy.zeros(nradbin**2, dtype='f4')
ind = slitno[m1] * nslitno + slitno[m2]
indr = radbin[m1] * nradbin + radbin[m2]
adj += numpy.bincount(ind, weights=area[m1], minlength=len(adj))
adj = adj.reshape(nslitno, nslitno)
adjr += numpy.bincount(indr, weights=area[m1], minlength=len(adjr))
adjr = adjr.reshape(nradbin, nradbin)
return adj, adjr
def adjacency_matrix(tilera, tiledec, fiberposfile=None):
"""Overlap area matrix between slit blocks and radial bins, given
tile ras and decs."""
# compute x & y on each tile to ra & dec
# match ras and decs together at some fiducial size
# (this ignores ellipticity, etc., but the slite blocks are pretty big)
#
if fiberposfile is None:
fiberposfile = os.path.join(os.environ['DESIMODEL'], 'data',
'focalplane', 'fiberpos.fits')
from astropy.io import fits
fpos = fits.getdata(fiberposfile)
# really slow, not vectorized.
pos = [[focalplane.xy2radec(tra, tdec, fx, fy)
for fx, fy in zip(fpos['x'], fpos['y'])]
for tra, tdec in zip(tilera, tiledec)]
pos = numpy.array(pos)
ras = pos[:, :, 0].ravel()
decs = pos[:, :, 1].ravel()
slitno = numpy.tile(fpos['slitblock']+fpos['petal']*20, len(tilera))
radbin = numpy.floor(numpy.sqrt(fpos['x']**2+fpos['y']**2)/20).astype('i4')
radbin = numpy.tile(radbin, len(tilera))
expnum = numpy.repeat(numpy.arange(len(tilera)), len(fpos))
rad = 1.4/60
m1, m2, d12 = match_radec(ras, decs, ras, decs, rad,
notself=True)
m = expnum[m1] != expnum[m2]
m1 = m1[m]
m2 = m2[m]
d12 = d12[m]
# area of intersection of two equal-size circles?
# area: 2r^2 arccos(d/2r)-0.5 d sqrt((2r-d)(2r+d))
area = (2*rad**2*numpy.arccos(d12/2./rad) -
0.5*d12*numpy.sqrt((2*rad-d12)*(2*rad+d12)))
nslitno = numpy.max(slitno)+1
nradbin = numpy.max(radbin)+1
adj = numpy.zeros(nslitno**2, dtype='f4')
adjr = numpy.zeros(nradbin**2, dtype='f4')
ind = slitno[m1]*nslitno+slitno[m2]
indr = radbin[m1]*nradbin+radbin[m2]
adj += numpy.bincount(ind, weights=area[m1], minlength=len(adj))
adj = adj.reshape(nslitno, nslitno)
adjr += numpy.bincount(indr, weights=area[m1], minlength=len(adjr))
adjr = adjr.reshape(nradbin, nradbin)
return adj, adjr
def plot_circles_radec(ax, circles, sample_per_circle):
""" Transforms points on a list of circles into radec and plots them
Parameters
----------
ax : matplotlib Axes object
circles : list
A list of Circle objects that needs plotting
sample_per_circle:
Number of points to plot around a circle
"""
ra_col = np.array([])
dec_col = np.array([])
for c in circles:
x, y = c.get_points(sample_per_circle)
ra, dec = xy2radec(telra, teldec, Column(x), Column(y))
ra_col = append(ra_col, ra)
dec_col = append(dec_col, dec)
plot(ra_col, dec_col, '.')
def transform2radec(telra, teldec, v):
"""Transforms a single point to radec
Temporary utility function. Can be replaced by xy2radec
"""
ra, dec = xy2radec(telra, teldec, Column([v[0]]), Column(v[1]))
return np.array([ra[0], dec[0]])
def transform_circle_radec(circle, sample):
x, y = circle.get_points(sample)
ra, dec = xy2radec(telra, teldec, Column(x), Column(y))
return ra, dec
fp = desimodel.io.load_fiberpos() #- load the fiberpos.fits file
telra, teldec = 10.0, 20.0 #- telescope central pointing at this RA,dec
# Create circles at each fiberpos
circles = []
for i in range(len(fp['X'])):
circles.append(Circle(fp['X'][i], fp['Y'][i], 6))
# circles = [Circle(-200, -300, 6)]
# Aggregate transformed points from each circle
ra_col = np.array([])
dec_col = np.array([])
for c in circles:
x, y = c.get_points(50)
ra, dec = xy2radec(telra, teldec, Column(x), Column(y))
ra_col = append(ra_col, ra)
dec_col = append(dec_col, dec)
ion()
figure(figsize=(8, 4))
# subplot(121)
# plot(fp['X'], fp['Y'], '.'); xlabel('X [mm]'); ylabel('Y [mm]')
ax = subplot(121)
plot(ra_col, dec_col, '.')
xlabel('RA [degrees]')
ylabel('dec [degrees]')
xlim([10.80, 10.90])
ylim([18.75, 18.85])