remove stickiness of plot attributes

src/dysh/plot/specplot.py

@@ -2,6 +2,8 @@
 Plot a spectrum using matplotlib
 """
 
+from copy import deepcopy
+
 import astropy.units as u
 import matplotlib.pyplot as plt
 import numpy as np
@@ -98,40 +100,43 @@ def plot(self, **kwargs):
             keyword=value arguments (need to describe these in a central place)
         """
         # xtype = 'velocity, 'frequency', 'wavelength'
-        self._plot_kwargs.update(kwargs)
         # if self._figure is None:
-        if True:
-            self._figure, self._axis = self._plt.subplots(figsize=self._plot_kwargs["figsize"])
+
+        # plot arguments for this call of plot(). i.e. non-sticky plot attributes
+        this_plot_kwargs = deepcopy(self._plot_kwargs)
+        this_plot_kwargs.update(kwargs)
+        if True:  # @todo deal with plot reuse (notebook vs script)
+            self._figure, self._axis = self._plt.subplots(figsize=this_plot_kwargs["figsize"])
         # else:
         #    self._axis.cla()
 
         s = self._spectrum
         sa = s.spectral_axis
-        lw = self._plot_kwargs["linewidth"]
-        xunit = self._plot_kwargs["xaxis_unit"]
-        yunit = self._plot_kwargs["yaxis_unit"]
+        lw = this_plot_kwargs["linewidth"]
+        xunit = this_plot_kwargs["xaxis_unit"]
+        yunit = this_plot_kwargs["yaxis_unit"]
         if xunit is not None:
             if "chan" in xunit:
                 sa = np.arange(len(sa))
-                self._plot_kwargs["xlabel"] = "Channel"
+                this_plot_kwargs["xlabel"] = "Channel"
             else:
                 # convert the x axis to the requested
                 # print(f"EQUIV {equiv} doppler_rest {sa.doppler_rest} [{rfq}] convention {convention}")
-                # sa = s.spectral_axis.to( self._plot_kwargs["xaxis_unit"], equivalencies=equiv,doppler_rest=rfq, doppler_convention=convention)
-                sa = s.velocity.to(self._plot_kwargs["xaxis_unit"], equivalencies=s.equivalencies)
-                self._plot_kwargs["xlabel"] = f"Velocity ({xunit})"
+                # sa = s.spectral_axis.to( this_plot_kwargs["xaxis_unit"], equivalencies=equiv,doppler_rest=rfq, doppler_convention=convention)
+                sa = s.velocity.to(this_plot_kwargs["xaxis_unit"], equivalencies=s.equivalencies)
+                this_plot_kwargs["xlabel"] = f"Velocity ({xunit})"
         sf = s.flux
         if yunit is not None:
             sf = s.flux.to(yunit)
-        self._axis.plot(sa, sf, color=self._plot_kwargs["color"], lw=lw)
-        self._axis.set_xlim(self._plot_kwargs["xmin"], self._plot_kwargs["xmax"])
-        self._axis.set_ylim(self._plot_kwargs["ymin"], self._plot_kwargs["ymax"])
+        self._axis.plot(sa, sf, color=this_plot_kwargs["color"], lw=lw)
+        self._axis.set_xlim(this_plot_kwargs["xmin"], this_plot_kwargs["xmax"])
+        self._axis.set_ylim(this_plot_kwargs["ymin"], this_plot_kwargs["ymax"])
         self._axis.tick_params(axis="both", which="both", bottom=True, top=True, left=True, right=True, direction="in")
-        if self._plot_kwargs["grid"]:
+        if this_plot_kwargs["grid"]:
             self._axis.grid(visible=True, which="major", axis="both", lw=lw / 2, color="k", alpha=0.33)
             self._axis.grid(visible=True, which="minor", axis="both", lw=lw / 2, color="k", alpha=0.22, linestyle="--")
 
-        self._set_labels(**self._plot_kwargs)
+        self._set_labels(**this_plot_kwargs)
         # self._axis.axhline(y=0,color='red',lw=2)
         self.refresh()