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skyweaver.viz.sky

Sky-track plotting utilities.

plot_sky_track 

plot_sky_track(track, ax=None, *, cmap=None, color=None, alpha=1.0, lw=1.5)

Plot a satellite sky track in polar alt-az coordinates.

Source code in src/skyweaver/viz/sky.py 
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def plot_sky_track(
    track: SkyTrack,
    ax: PolarAxes | None = None,
    *,
    cmap: str | Colormap | None = None,
    color: str | None = None,
    alpha: float = 1.0,
    lw: float = 1.5,
) -> PolarAxes:
    """Plot a satellite sky track in polar alt-az coordinates."""
    if ax is None:
        _, ax0 = plt.subplots(subplot_kw={"projection": "polar"}, figsize=(7, 7))
        ax = cast(PolarAxes, ax0)

    passes = track.passes()

    if cmap is None:
        pass_colors = [color] * len(passes)
    else:
        cmap_obj = colormaps[cmap] if isinstance(cmap, str) else cmap

        n_passes = len(passes)
        if n_passes == 0:
            pass_colors = []
        elif n_passes == 1:
            pass_colors = [cmap_obj(0.5)]
        else:
            pass_colors = list(cmap_obj(np.linspace(0.0, 1.0, n_passes)))

    for sat_pass, pass_color in zip(passes, pass_colors, strict=True):
        _plot_single_pass(
            sat_pass,
            ax,
            color=pass_color,
            alpha=alpha,
            lw=lw,
        )

    ax.set_title(f"Sky track: {track.orbit.name} at {track.observatory.name}")
    ax.set_theta_zero_location("N")
    ax.set_theta_direction(-1)
    ax.set_ylim(90.0, 0.0)
    ax.set_rgrids([30.0, 60.0, 90.0])
    ax.set_rlabel_position(67.5)
    ax.grid(True)

    return ax

plot_sky_track_healpix 

plot_sky_track_healpix(track, *, nside=32, unique_per_pass=True, cmap=None, title=None, unit='counts', half_sky=True, rot=(0, 90, 180), graticule=True, **kwargs)

Plot a HEALPix map of a sky track in local alt-az coordinates.

Parameters:

Name Type Description Default
track SkyTrack

Sky track to bin into HEALPix pixels.

 required
nside int

HEALPix nside parameter.

 32
unique_per_pass bool

If True, count each pixel at most once per pass.

 True
cmap

Optional colormap passed to healpy.

 None
title str | None

Plot title. If None, a default title is used.

 None
unit str

Colorbar/unit label passed to healpy.

 'counts'
half_sky bool

Whether to use a half-sky orthographic projection.

 True
rot list[float] | tuple[float, float, float]

Rotation passed to healpy.orthview.

 (0, 90, 180)
graticule bool

If True, overlay a graticule and cardinal directions.

 True
**kwargs

Additional keyword arguments passed to healpy.orthview.

 {}

Returns:

Type Description
ndarray

The HEALPix map that was plotted.
Source code in src/skyweaver/viz/sky.py 
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def plot_sky_track_healpix(
    track: SkyTrack,
    *,
    nside: int = 32,
    unique_per_pass: bool = True,
    cmap=None,
    title: str | None = None,
    unit: str = "counts",
    half_sky: bool = True,
    rot: list[float] | tuple[float, float, float] = (0, 90, 180),
    graticule: bool = True,
    **kwargs,
) -> np.ndarray:
    """Plot a HEALPix map of a sky track in local alt-az coordinates.

    Parameters
    ----------
    track
        Sky track to bin into HEALPix pixels.
    nside
        HEALPix nside parameter.
    unique_per_pass
        If True, count each pixel at most once per pass.
    cmap
        Optional colormap passed to healpy.
    title
        Plot title. If None, a default title is used.
    unit
        Colorbar/unit label passed to healpy.
    half_sky
        Whether to use a half-sky orthographic projection.
    rot
        Rotation passed to ``healpy.orthview``.
    graticule
        If True, overlay a graticule and cardinal directions.
    **kwargs
        Additional keyword arguments passed to ``healpy.orthview``.

    Returns
    -------
    np.ndarray
        The HEALPix map that was plotted.
    """
    healpix_map = track.to_healpix(
        nside=nside,
        unique_per_pass=unique_per_pass,
    )

    if title is None:
        title = f"Sky HEALPix map: {track.orbit.name} at {track.observatory.name}"

    hp.orthview(
        healpix_map,
        rot=rot,
        half_sky=half_sky,
        cmap=cmap,
        unit=unit,
        title=title,
        **kwargs,
    )

    if graticule:
        hp.visufunc.graticule(15, 30, ls=":", color="whitesmoke", alpha=0.5)

        hp.visufunc.projtext(
            0,
            21,
            "N",
            lonlat=True,
            ha="center",
            va="center",
            fontsize=14,
            color="w",
        )
        hp.visufunc.projtext(
            90,
            21,
            "E",
            lonlat=True,
            ha="center",
            va="center",
            fontsize=14,
            color="w",
        )
        hp.visufunc.projtext(
            180,
            21,
            "S",
            lonlat=True,
            ha="center",
            va="center",
            fontsize=14,
            color="w",
        )
        hp.visufunc.projtext(
            270,
            21,
            "W",
            lonlat=True,
            ha="center",
            va="center",
            fontsize=14,
            color="w",
        )

    return healpix_map