fixup

src/Visualization/Python/PlotPowerMonitors.py

@@ -133,6 +133,14 @@ def plot_power_monitors(volfiles: Union[spectre_h5.H5Vol,
     ax_colspan.set_xlabel("Mode number")
 
 
+def parse_step(ctx, param, value):
+    if value is None:
+        return None
+    if value.lower() == "last":
+        return -1
+    return int(value)
+
+
 @click.command()
 @click.argument("h5_files",
                 nargs=-1,
@@ -144,9 +152,9 @@ def plot_power_monitors(volfiles: Union[spectre_h5.H5Vol,
               "-d",
               help=("Name of volume data subfile within the h5 files."))
 @click.option("--step",
-              type=int,
-              help=("Observation step number. "
-                    "Specify '-1' for the last step in the file. "
+              callback=parse_step,
+              help=("Observation step number. Specify '-1' or 'last' "
+                    "for the last step in the file (default). "
                     "Mutually exclusive with '--time'."))
 @click.option("--time",
               type=float,
@@ -161,7 +169,8 @@ def plot_power_monitors(volfiles: Union[spectre_h5.H5Vol,
               "-b",
               "block_or_group_names",
               multiple=True,
-              help=("Names of blocks or block groups to analyze."))
+              help=("Names of blocks or block groups to analyze. "
+                    "Can be specified multiple times."))
 @click.option("--list-vars",
               "-l",
               is_flag=True,
@@ -213,7 +222,9 @@ def plot_power_monitors_command(h5_files, subfile_name, step, time,
     dim = volfiles[0].get_dimension()
 
     # Select observation
-    if (step is None) == (time is None):
+    if step is None and time is None:
+        step = -1
+    elif step is not None and time is not None:
         raise click.UsageError(
             f"Specify either '--step' (in [0, {len(obs_ids) - 1}], or -1) or "
             f"'--time' (in [{obs_values[0]:g}, {obs_values[-1]:g}]).")