Ejemplo n.º 1
0
	def setHdus(self, p):
		self.hdus = p
		self.table = fits_table(self.hdus[1].data)[0]
		T = self.table
		self.aa = T.aa.astype(float)
		self.kk = T.kk.astype(float)
		self.airmass = T.airmass
Ejemplo n.º 2
0
	def readPhotoObj(self, run, camcol, field, filename=None):
		obj = PhotoObj(run, camcol, field)
		if filename is None:
			fn = self.getPath('photoObj', run, camcol, field)
		else:
			fn = filename
		obj.table = fits_table(fn)
		return obj
Ejemplo n.º 3
0
	def getMaskPlane(self, name):
		# Mask planes are described in HDU 11 (the last HDU)
		if self.maskmap is None:
			self.maskmap = {}
			T = fits_table(self.hdus[-1].data)
			#print 'Got mask definition table'
			#T.about()
			T.cut(T.defname == 'S_MASKTYPE')
			for k,v in zip(T.attributename, T.value):
				k = k.replace('S_MASK_', '')
				if k == 'S_NMASK_TYPES':
					continue
				#print '  Mask', k, '=', v
				self.maskmap[k] = v
		if not name in self.maskmap:
			raise RuntimeError('Unknown mask plane \"%s\"' % name)

		return fits_table(self.hdus[1 + self.maskmap[name]].data)
Ejemplo n.º 4
0
	def getPsfAtPoints(self, bandnum, x, y):
		'''
		Reconstruct the SDSS model PSF from KL basis functions.

		x,y can be scalars or 1-d numpy arrays.

		Return value:
		if x,y are scalars: a PSF image
		if x,y are arrays:  a list of PSF images
		'''
		rtnscalar = np.isscalar(x) and np.isscalar(y)
		x = np.atleast_1d(x)
		y = np.atleast_1d(y)
		psf = fits_table(self.hdus[bandnum+1].data)
		psfimgs = None
		(outh, outw) = (None,None)

		# From the IDL docs:
		# http://photo.astro.princeton.edu/photoop_doc.html#SDSS_PSF_RECON
		#   acoeff_k = SUM_i{ SUM_j{ (0.001*ROWC)^i * (0.001*COLC)^j * C_k_ij } }
		#   psfimage = SUM_k{ acoeff_k * RROWS_k }
		for k in range(len(psf)):
			nrb = psf.nrow_b[k]
			ncb = psf.ncol_b[k]
			c = psf.c[k].reshape(5, 5)
			c = c[:nrb,:ncb]
			(gridi,gridj) = np.meshgrid(range(nrb), range(ncb))

			if psfimgs is None:
				psfimgs = [np.zeros_like(psf.rrows[k]) for xy
						   in np.broadcast(x,y)]
				(outh,outw) = (psf.rnrow[k], psf.rncol[k])
			else:
				assert(psf.rnrow[k] == outh)
				assert(psf.rncol[k] == outw)

			for i,(xi,yi) in enumerate(np.broadcast(x,y)):
				#print 'xi,yi', xi,yi
				acoeff_k = np.sum(((0.001 * xi)**gridi * (0.001 * yi)**gridj * c))
				if False: # DEBUG
					print 'coeffs:', (0.001 * xi)**gridi * (0.001 * yi)**gridj
					print 'c:', c
					for (coi,ci) in zip(((0.001 * xi)**gridi * (0.001 * yi)**gridj).ravel(), c.ravel()):
						print 'co %g, c %g' % (coi,ci)
					print 'acoeff_k', acoeff_k

				#print 'acoeff_k', acoeff_k.shape, acoeff_k
				#print 'rrows[k]', psf.rrows[k].shape, psf.rrows[k]
				psfimgs[i] += acoeff_k * psf.rrows[k]

		psfimgs = [img.reshape((outh,outw)) for img in psfimgs]
		if rtnscalar:
			return psfimgs[0]
		return psfimgs
Ejemplo n.º 5
0
	def setHdus(self, p):
		self.hdus = p
		t = fits_table(p[6].data)
		# the table has only one row...
		assert(len(t) == 1)
		t = t[0]
		#self.table = t
		self.gain = t.gain
		self.dark_variance = t.dark_variance
		self.sky = t.sky
		self.skyerr = t.skyerr
		self.psp_status = t.status
		# Double-Gaussian PSF params
		self.dgpsf_s1 = t.psf_sigma1_2g
		self.dgpsf_s2 = t.psf_sigma2_2g
		self.dgpsf_b  = t.psf_b_2g
		# summary PSF width (sigmas)
		self.psf_fwhm = t.psf_width * (2.*np.sqrt(2.*np.log(2.)))
Ejemplo n.º 6
0
	def readFrame(self, run, camcol, field, band, filename=None):
		'''
		http://data.sdss3.org/datamodel/files/BOSS_PHOTOOBJ/frames/RERUN/RUN/CAMCOL/frame.html
		'''
		f = Frame(run, camcol, field, band)
		# ...
		if filename is None:
			fn = self.getPath('frame', run, camcol, field, band)
		else:
			fn = filename
		#print 'reading file', fn
 		p = pyfits.open(fn)
		#print 'got', len(p), 'HDUs'
		# in nanomaggies
		f.image = p[0].data
		# converts counts -> nanomaggies
		f.calib = p[1].data
		# table with val,x,y -- binned; use bilinear interpolation to expand
		sky = p[2].data
		f.sky = sky.field('allsky')[0]
		#print 'sky shape', f.sky.shape
		if len(f.sky.shape) != 2:
			f.sky = f.sky.reshape((-1, 256))
		f.skyxi = sky.field('xinterp')[0]
		f.skyyi = sky.field('yinterp')[0]
		#print 'p3:', p[3]
		# table -- asTrans structure
		tab = fits_table(p[3].data)
		assert(len(tab) == 1)
		tab = tab[0]
		# DR7 has NODE, INCL in radians...
		f.astrans = AsTrans(run, camcol, field, band,
							node=np.deg2rad(tab.node), incl=np.deg2rad(tab.incl),
							astrans=tab, cut_to_band=False)
							
		return f