plot_xsecs

plot_xsecs(processes="all", layout="overlay", fig=None, ax=None, energy_unit="eV", xsec_unit="Mb", energy_log=True, xsecs_log=True, title=None, grid=True, show=True, save=False, filename="")

Plots photo cross sections against photon energy or wavelength. Drawing, unit conversion, and labelling are delegated to jaff.plotting.Plotter.plot_xsec. Does nothing (logs a message and returns None) if xsecs_dict is None or no requested process has data. Cross-section data are stored as photon energies in eV and cross sections in cm²; both are converted to the requested units before plotting.

Parameters

processes : str or list[str] or None, optional

Which cross-section processes to draw. "all" (default) or None plots every process that has data; a single key or a list of keys selects a subset. Valid keys: "photo_absorption", "photodecay" (the reaction's single ionization/dissociation channel). An invalid key raises KeyError.

layout : str, optional

"overlay" (default) draws all processes on one axes; "subplots" gives each process its own stacked panel.

fig, ax : matplotlib.figure.Figure / matplotlib.axes.Axes or None, optional

Existing figure/axes to draw on (overlay layout only). Created if None.

energy_unit : str, optional

Horizontal-axis unit: "eV" (default), "erg", "nm", or "um".

xsec_unit : str, optional

Cross-section unit: "Mb" (default), "cm^2", or "barn".

energy_log : bool, optional

Log-scale the energy axis. Default True.

xsecs_log : bool, optional

Log-scale the cross-section axis. Default True.

title : str or None, optional

Plot title. Defaults to the LaTeX reaction equation.

grid : bool, optional

Draw a grid. Default True.

show : bool, optional

Display the figure. Default True.

save : bool, optional

Save to filename (format inferred from the extension). Default False.

filename : str, optional

Output path. Defaults to "<reaction>_<process>.png".

Returns

tuple[matplotlib.figure.Figure, matplotlib.axes.Axes] or None

The figure and axes (overlay) or array of axes (subplots); None when there is no data to plot.