Exemple #1
0
def MWA_Tile_advanced(za, az, freq=100.0e6, delays=None, zenithnorm=True, power=True, jones=False):
    """
    Use the new MWA tile model from mwa_tile.py that includes mutual coupling
    and the simulated dipole response. Returns the XX and YY response to an
    unpolarised source.

    if jones=True, will return the Jones matrix instead

    delays should be a numpy array of size (2,16), although a (16,) list or a (16,) array will also be accepted    
    
    """
    if isinstance(delays,list):
        delays=numpy.array(delays)

    if delays.shape == (16,):
        try:
            delays=numpy.repeat(numpy.reshape(delays,(1,16)),2,axis=0)
        except:
            logger.error('Unable to convert delays (shape=%s) to (2,16)' % (delays.shape))
            return None
    assert delays.shape == (2,16), "Delays %s have unexpected shape %s" % (delays,delays.shape)
    
    logger.setLevel(logging.DEBUG)
    d = mwa_tile.Dipole(type='lookup') 
    logger.debug("Delays: "+str(delays))
    tile = mwa_tile.ApertureArray(dipoles=[d]*16)   # tile of identical dipoles
    j = tile.getResponse(az,za,freq,delays=delays)
    if jones:
        return j
    vis = mwa_tile.makeUnpolInstrumentalResponse(j,j)
    if not power:
        return (numpy.sqrt(vis[:,:,0,0].real),numpy.sqrt(vis[:,:,1,1].real))
    else:
        return (vis[:,:,0,0].real,vis[:,:,1,1].real)
def local_beam(za,
               az,
               freq,
               delays=None,
               zenithnorm=True,
               power=True,
               jones=False,
               interp=True,
               pixels_per_deg=5,
               amps=None):
    '''Code pulled from mwapy that generates the MWA beam response - removes unecessary extra code from mwapy/pb
        - delays is a 2x16 array, with the first 16 delays for the XX, second 16
            for the YY pol. values match what you find in the metafits file
        - amps are the amplitudes of each individual dipole, again in a 2x16,
            with XX first then YY'''
    tile = beam_full_EE.ApertureArray(MWAPY_H5PATH, freq)
    mybeam = beam_full_EE.Beam(tile, delays, amps)
    if interp:
        j = mybeam.get_interp_response(az, za, pixels_per_deg)
    else:
        j = mybeam.get_response(az, za)
    if zenithnorm == True:
        j = tile.apply_zenith_norm_Jones(j)  #Normalise

    #Use swapaxis to place jones matrices in last 2 dimensions
    #insead of first 2 dims.
    if len(j.shape) == 4:
        j = swapaxes(swapaxes(j, 0, 2), 1, 3)
    elif len(j.shape) == 3:  #1-D
        j = swapaxes(swapaxes(j, 1, 2), 0, 1)
    else:  #single value
        pass

    if jones:
        return j

    #Use mwa_tile makeUnpolInstrumentalResponse because we have swapped axes
    vis = mwa_tile.makeUnpolInstrumentalResponse(j, j)
    if not power:
        return (sqrt(vis[:, :, 0, 0].real), sqrt(vis[:, :, 1, 1].real))
    else:
        return (vis[:, :, 0, 0].real, vis[:, :, 1, 1].real)
Exemple #3
0
def local_beam(za,
               az,
               freq,
               delays=None,
               zenithnorm=True,
               power=True,
               jones=False,
               interp=True,
               pixels_per_deg=5,
               amps=None):
    '''Code pulled my mwapy that generates the MWA beam response - removes unecessary extra code from mwapy/pb'''
    tile = beam_full_EE.ApertureArray(MWAPY_H5PATH, freq)
    mybeam = beam_full_EE.Beam(tile, delays, amps)
    if interp:
        j = mybeam.get_interp_response(az, za, pixels_per_deg)
    else:
        j = mybeam.get_response(az, za)
    if zenithnorm == True:
        j = tile.apply_zenith_norm_Jones(j)  #Normalise

    #Use swapaxis to place jones matrices in last 2 dimensions
    #insead of first 2 dims.
    if len(j.shape) == 4:
        j = swapaxes(swapaxes(j, 0, 2), 1, 3)
    elif len(j.shape) == 3:  #1-D
        j = swapaxes(swapaxes(j, 1, 2), 0, 1)
    else:  #single value
        pass

    if jones:
        return j

    #Use mwa_tile makeUnpolInstrumentalResponse because we have swapped axes
    vis = mwa_tile.makeUnpolInstrumentalResponse(j, j)
    if not power:
        return (sqrt(vis[:, :, 0, 0].real), sqrt(vis[:, :, 1, 1].real))
    else:
        return (vis[:, :, 0, 0].real, vis[:, :, 1, 1].real)
Exemple #4
0
def MWA_Tile_full_EE(za,
                     az,
                     freq,
                     delays=None,
                     zenithnorm=True,
                     power=True,
                     jones=False,
                     interp=True,
                     pixels_per_deg=5):
    """
    Use the new MWA tile model from beam_full_EE.py that includes mutual coupling
    and the simulated dipole response. Returns the XX and YY response to an
    unpolarised source.

    if jones=True, will return the Jones matrix instead of the XX,YY response.
    In this case, the power flag will be ignored.
    If interp=False, the pixels_per_deg will be ignored

    delays should be a numpy array of size (2,16), although a (16,) list or a (16,) array will also be accepted

    az - azimuth angles (radians), north through east.
    za - zenith angles (radian)
    """
    # Convert za and az into 2D numpy arrays, because the Advanced and FullEE models require that format.
    if type(za) is list:
        za = numpy.array(za)
    if type(az) is list:
        az = numpy.array(az)

    if (isinstance(za, float)) and (isinstance(
            az, float)):  # Convert float to 2D array
        za = numpy.array([[za]])
        az = numpy.array([[az]])
        dtype = 'float'
    elif (isinstance(za, numpy.ndarray)) and (isinstance(az, numpy.ndarray)):
        if (len(za.shape) == 1) and (len(az.shape)
                                     == 1):  # 1D array, convert to 2D array
            za = za[None, :]
            az = az[None, :]
            dtype = '1D'
        elif (len(za.shape) == 2) and (len(az.shape) == 2):
            dtype = '2D'
        else:
            dtype = 'bad'
    else:
        dtype = 'bad'

    if dtype == 'bad':
        logger.error(
            'ERROR - az/za data types must be the same, and either floats or 1 or 2 dimensional arrays'
        )
        return None

    tile = beam_full_EE.get_AA_Cached(target_freq_Hz=freq)
    mybeam = beam_full_EE.Beam(
        tile, delays, amps=numpy.ones([2, 16])
    )  # calling with amplitudes=1 every time - otherwise they get overwritten !!!
    if interp:
        j = mybeam.get_interp_response(az, za, pixels_per_deg)
    else:
        j = mybeam.get_response(az, za)
    if zenithnorm:
        j = tile.apply_zenith_norm_Jones(j)  # Normalise

    # TODO: do frequency interpolation here (with 2nd adjacent beam)

    # Use swapaxis to place jones matrices in last 2 dimensions
    # insead of first 2 dims.
    if len(j.shape) == 4:
        j = numpy.swapaxes(numpy.swapaxes(j, 0, 2), 1, 3)
    elif len(j.shape) == 3:  # 1-D
        j = numpy.swapaxes(numpy.swapaxes(j, 1, 2), 0, 1)
    else:  # single value
        pass

    if jones:
        if dtype == 'float':
            return j[0][0]
        elif dtype == '1D':
            return j[0]
        else:
            return j

    # Use mwa_tile makeUnpolInstrumentalResponse because we have swapped axes
    vis = mwa_tile.makeUnpolInstrumentalResponse(j, j)
    if not power:
        xx, yy = (numpy.sqrt(vis[:, :, 0,
                                 0].real), numpy.sqrt(vis[:, :, 1, 1].real))
    else:
        xx, yy = (vis[:, :, 0, 0].real, vis[:, :, 1, 1].real)

    if dtype == 'float':
        return xx[0][0], yy[0][0]
    elif dtype == '1D':
        return xx[0], yy[0]
    else:
        return xx, yy
Exemple #5
0
def MWA_Tile_advanced(za,
                      az,
                      freq=100.0e6,
                      delays=None,
                      zenithnorm=None,
                      power=True,
                      jones=False):
    """
    Use the new MWA tile model from mwa_tile.py that includes mutual coupling
    and the simulated dipole response. Returns the XX and YY response to an
    unpolarised source.

    if jones=True, will return the Jones matrix instead

    delays should be a numpy array of size (2,16), although a (16,) list or a (16,) array will also be accepted

    """
    if isinstance(delays, list):
        delays = numpy.array(delays)

    # Convert za and az into 2D numpy arrays, because the Advanced and FullEE models require that format.
    if type(za) is list:
        za = numpy.array(za)
    if type(az) is list:
        az = numpy.array(az)

    if (isinstance(za, float)) and (isinstance(
            az, float)):  # Convert float to 2D array
        za = numpy.array([[za]])
        az = numpy.array([[az]])
        dtype = 'float'
    elif (isinstance(za, numpy.ndarray)) and (isinstance(az, numpy.ndarray)):
        if (len(za.shape) == 1) and (len(az.shape)
                                     == 1):  # 1D array, convert to 2D array
            za = za[None, :]
            az = az[None, :]
            dtype = '1D'
        elif (len(za.shape) == 2) and (len(az.shape) == 2):
            dtype = '2D'
        else:
            dtype = 'bad'
    else:
        dtype = 'bad'

    if dtype == 'bad':
        logger.error(
            'ERROR - az/za data types must be the same, and either floats or 1 or 2 dimensional arrays'
        )
        return None

    if zenithnorm:
        logger.warning(
            'ERROR: MWA_Tile_advanced does not use the zenithnorm parameter.')

    if delays.shape == (16, ):
        try:
            delays = numpy.repeat(numpy.reshape(delays, (1, 16)), 2, axis=0)
        except Exception:
            logger.error('Unable to convert delays (shape=%s) to (2,16)' %
                         (delays.shape))
            return None
    assert delays.shape == (
        2, 16), "Delays %s have unexpected shape %s" % (delays, delays.shape)

    logger.debug("Delays: " + str(delays))
    tile = mwa_tile.get_AA_Cached()  # tile of identical dipoles
    j = tile.getResponse(az, za, freq, delays=delays)
    if jones:
        if dtype == 'float':
            return j[0][0]
        elif dtype == '1D':
            return j[0]
        else:
            return j

    vis = mwa_tile.makeUnpolInstrumentalResponse(j, j)
    if not power:
        xx, yy = (numpy.sqrt(vis[:, :, 0,
                                 0].real), numpy.sqrt(vis[:, :, 1, 1].real))
    else:
        xx, yy = (vis[:, :, 0, 0].real, vis[:, :, 1, 1].real)

    if dtype == 'float':
        return xx[0][0], yy[0][0]
    elif dtype == '1D':
        return xx[0], yy[0]
    else:
        return xx, yy