diagnostic_plots.py 文件源码

def hessPlot(targ_ra, targ_dec, data, iso, g_radius, nbhd):
    """Hess plot"""

    mag_g = data[mag_g_dred_flag]
    mag_r = data[mag_r_dred_flag]

    filter_s = star_filter(data)

    plt.title('Hess')

    c1 = SkyCoord(targ_ra, targ_dec, unit='deg')

    r_near = 2.*g_radius # annulus begins at 3*g_radius away from centroid
    r_far = np.sqrt(5.)*g_radius # annulus has same area as inner area

    inner = (c1.separation(SkyCoord(data['RA'], data['DEC'], unit='deg')).deg < g_radius)
    outer = (c1.separation(SkyCoord(data['RA'], data['DEC'], unit='deg')).deg > r_near) & (c1.separation(SkyCoord(data['RA'], data['DEC'], unit='deg')).deg < r_far)

    xbins = np.arange(-0.5, 1.1, 0.1)
    ybins = np.arange(16., 24.5, 0.5)

    foreground = np.histogram2d(mag_g[inner & filter_s] - mag_r[inner & filter_s], mag_g[inner & filter_s], bins=[xbins, ybins])
    background = np.histogram2d(mag_g[outer & filter_s] - mag_r[outer & filter_s], mag_g[outer & filter_s], bins=[xbins, ybins])

    fg = foreground[0].T
    bg = background[0].T

    fg_abs = np.absolute(fg)
    bg_abs = np.absolute(bg)

    mask_abs = fg_abs + bg_abs
    mask_abs[mask_abs == 0.] = np.nan # mask signficiant zeroes

    signal = fg - bg
    signal = np.ma.array(signal, mask=np.isnan(mask_abs)) # mask nan

    cmap = matplotlib.cm.viridis
    cmap.set_bad('w', 1.)
    plt.pcolormesh(xbins, ybins, signal, cmap=cmap)

    plt.colorbar()

    ugali.utils.plotting.drawIsochrone(iso, lw=2, c='k', zorder=10, label='Isocrhone')

    plt.axis([-0.5, 1.0, 16, 24])
    plt.gca().invert_yaxis()
    plt.gca().set_aspect(1./4.)
    plt.xlabel('g-r (mag)')
    plt.ylabel('g (mag)')

    #ax = plt.gca()
    #divider = make_axes_locatable(ax)
    #cax = divider.append_axes('right', size = '5%', pad=0)
    #plt.colorbar(cax=cax)