start working on figures

py/LSLGA/desiutil.py

@@ -21,10 +21,6 @@
 from matplotlib.patches import Ellipse
 from astropy.coordinates import SkyCoord, HeliocentricTrueEcliptic, ICRS, Longitude
 import astropy.units as u
-from astropy.time import Time
-from astropy.utils import iers
-from .iers import freeze_iers
-
 
 def plot_slices(x, y, x_lo, x_hi, y_cut, num_slices=5, min_count=100, axis=None,
                 set_ylim_from_stats=True, scatter=True):
@@ -1003,114 +999,3 @@ def plot_sky_binned(ra, dec, weights=None, data=None, plot_type='grid',
         return ax
 
 
-def plot_iers(which='auto', num_points=500, save=None):
-    """Plot IERS data from 2015-2025.
-
-    Plots the UT1-UTC time offset and polar x,y motions over a 10-year
-    period that includes the DESI survey, to demonstrate the time ranges
-    when different sources (IERS-A, IERS-B) are used and where values
-    are predicted then fixed.
-
-    This function is primarily intended to document and debug the
-    :func:`desiutil.iers.freeze_iers` function.
-
-    Requires that the matplotlib package is installed.
-
-    Parameters
-    ----------
-    which : {'auto', 'A', 'B', 'frozen'}
-        Select which IERS table source to use.  The default 'auto' matches
-        the internal astropy default.  Use 'A' or 'B' to force the source
-        to be either the latest IERS-A table (which will be downloaded),
-        or the IERS-B table packaged with the current version of astropy.
-        The 'frozen' option calls :func:`~desiutil.iers.freeze_iers`.
-    num_points : :class:`int`, optional
-        The number of times covering 2015-25 to calculate and plot.
-    save : :class:`str`, optional
-        Name of file where plot should be saved.  Format is inferred from
-        the extension.
-
-    Returns
-    -------
-    :func:`tuple`
-        Tuple (figure, axes) returned by ``plt.subplots()``.
-    """
-    #
-    # These values are copied from the desisurvey config.yaml file.
-    # They may or may not reflect the latest configuration.
-    #
-    # Survey nominally starts on night of this date. Format is YYYY-MM-DD.
-    first_day = date(2019, 12, 1)
-    # Survey nominally ends on morning of this date. Format is YYYY-MM-DD.
-    last_day = date(2024, 11, 30)
-
-    # Calculate UTC midnight timestamps covering 2015 - 2025
-    start = Time('2015-01-01 00:00')
-    stop = Time('2025-01-01 00:00')
-    mjd = np.linspace(start.mjd, stop.mjd, num_points)
-    times = Time(mjd, format='mjd')
-
-    t_lo = matplotlib.dates.date2num(start.datetime)
-    t_hi = matplotlib.dates.date2num(stop.datetime)
-    t = np.linspace(t_lo, t_hi, num_points)
-
-    t_start = matplotlib.dates.date2num(first_day)
-    t_stop = matplotlib.dates.date2num(last_day)
-
-    # Load the specified IERS table.
-    if which == 'auto':
-        iers = iers.IERS_Auto.open()
-    elif which == 'B':
-        iers = iers.IERS_B.open()
-    elif which == 'A':
-        # This requires network access to download the latest file.
-        iers = iers.IERS_A.open(iers.conf.iers_auto_url)
-    elif which == 'frozen':
-        freeze_iers()
-        iers = iers.IERS_Auto.open()
-    else:
-        raise ValueError('Invalid which option.')
-
-    # Calculate UT1-UTC using the IERS table.
-    dt, dt_status = iers.ut1_utc(times, return_status=True)
-    dt = dt.to(u.s).value
-
-    # Calculate polar x,y motion using the IERS table.
-    pmx, pmy, pm_status = iers.pm_xy(times, return_status=True)
-    pmx = pmx.to(u.arcsec).value
-    pmy = pmy.to(u.arcsec).value
-
-    assert np.all(dt_status == pm_status)
-    codes = np.unique(dt_status)
-
-    fig, ax = plt.subplots(2, 1, sharex=True, figsize=(8, 6))
-
-    labels = {-2: 'Fixed', 0: 'IERS-B', 1: 'IERS-A', 2: 'Predict'}
-    styles = {-2: 'r:', 0: 'b-', 1: 'go', 2: 'r--'}
-    ms = 3
-    for code in codes:
-        sel = dt_status == code
-        ax[0].plot(t[sel], dt[sel], styles[code], ms=ms, label=labels[code])
-        ax[1].plot(t[sel], pmx[sel], styles[code], ms=ms, label='Polar x')
-        ax[1].plot(t[sel], pmy[sel], styles[code], ms=ms, label='Polar y')
-
-    ax[0].legend(ncol=4)
-    ax[0].set_ylabel('UT1 - UTC [s]')
-    ax[1].set_ylabel('Polar x,y motion [arcsec]')
-
-    for i in range(2):
-        # Vertical lines showing the survey start / stop dates.
-        ax[i].axvline(t_start, ls='--', c='k')
-        ax[i].axvline(t_stop, ls='--', c='k')
-
-    # Use year labels for the horizontal axis.
-    xaxis = ax[1].xaxis
-    xaxis.set_major_locator(matplotlib.dates.YearLocator())
-    xaxis.set_major_formatter(matplotlib.dates.DateFormatter('%Y'))
-    ax[i].set_xlim(start.datetime, stop.datetime)
-
-    plt.tight_layout()
-    if save:
-        plt.savefig(save)
-
-    return fig, ax