lsst.pipe.tasks.astrometry Namespace Reference

Classes
class	AstrometryConfig
class	AstrometryTask
	Match input sources with a reference catalog and solve for the Wcs More...

Functions
def	showAstrometry
	Show results of astrometry fitting. More...

Function Documentation

def lsst.pipe.tasks.astrometry.showAstrometry	(		exposure,
			wcs,
			allMatches,
			useMatches,
			frame = 0,
			title = None,
			pause = False
	)

Show results of astrometry fitting.

Parameters

exposure	Image to display
wcs	Astrometric solution
allMatches	List of all astrometric matches (including rejects)
useMatches	List of used astrometric matches
frame	Frame number for display
title	Title for display
pause	Pause to allow viewing of the display and optional debugging?

• Matches are shown in yellow if used in the Wcs solution, otherwise red
  • +: Detected objects
  • x: Catalogue objects

Definition at line 411 of file astrometry.py.

def showAstrometry(exposure, wcs, allMatches, useMatches, frame=0, title=None, pause=False):
    """!Show results of astrometry fitting

    \param exposure Image to display
    \param wcs Astrometric solution
    \param allMatches List of all astrometric matches (including rejects)
    \param useMatches List of used astrometric matches
    \param frame Frame number for display
    \param title Title for display
    \param pause Pause to allow viewing of the display and optional debugging?

    - Matches are shown in yellow if used in the Wcs solution, otherwise red
     - +: Detected objects
     - x: Catalogue objects
    """
    import lsst.afw.display.ds9 as ds9
    ds9.mtv(exposure, frame=frame, title=title)

    useIndices = set(m.second.getId() for m in useMatches)

    radii = []
    with ds9.Buffering():
        for i, m in enumerate(allMatches):
            x, y = m.second.getX(), m.second.getY()
            pix = wcs.skyToPixel(m.first.getCoord())

            isUsed = m.second.getId() in useIndices
            if isUsed:
                radii.append(numpy.hypot(pix[0] - x, pix[1] - y))

            color = ds9.YELLOW if isUsed else ds9.RED

            ds9.dot("+", x, y, size=10, frame=frame, ctype=color)
            ds9.dot("x", pix[0], pix[1], size=10, frame=frame, ctype=color)

    radii = numpy.array(radii)
    print "<dr> = %.4g +- %.4g pixels [%d/%d matches]" % (radii.mean(), radii.std(),
                                                          len(useMatches), len(allMatches))

    if pause:
        import sys
        while True:
            try:
                reply = raw_input("Debugging? [p]db [q]uit; any other key to continue... ").strip()
            except EOFError:
                reply = ""

            reply = reply.split()
            if len(reply) > 1:
                reply = reply[0]
            if reply == "p":
                import pdb;pdb.set_trace()
            elif reply == "q":
                sys.exit(1)
            else:
                break