Add XY_7_2 plot

Plots/XY/xy_7_2_lg.py

@@ -0,0 +1,94 @@
+"""
+xy_7_2_lg.py
+===============
+An example of a double y plot: two separate line with their own unique axis.
+
+- Original NCL script: https://www.ncl.ucar.edu/Applications/Scripts/xy_7.ncl
+- https://www.ncl.ucar.edu/Applications/Images/xy_7_2_lg.png
+
+"""
+
+###############################################################################
+# Import modules
+# ===============
+
+import matplotlib.pyplot as plt
+import numpy as np
+import xarray as xr
+import geocat.datafiles
+
+################################################################################
+# Open data file and extract a slice of the data
+# ===============================================
+
+dset = xr.open_dataset(geocat.datafiles.get("netcdf_files/TestData.xy3.nc"))
+ds = dset.isel(case=0, time=slice(0, 36))
+
+
+################################################################################
+# Create XY plot with two different Y axes
+# =========================================
+
+
+def nclize_axis(ax):
+    """
+    Utility function to make plots look like NCL plots
+    """
+    import matplotlib.ticker as tic
+
+    ax.tick_params(labelsize="small")
+    ax.minorticks_on()
+    ax.xaxis.set_minor_locator(tic.AutoMinorLocator(n=5))
+    ax.yaxis.set_minor_locator(tic.AutoMinorLocator(n=3))
+
+    # length and width are in points and may need to change depending on figure size etc.
+    ax.tick_params(
+        "both",
+        length=8,
+        width=1.5,
+        which="major",
+        bottom=True,
+        top=True,
+        left=True,
+        right=True,
+    )
+    ax.tick_params(
+        "both",
+        length=5,
+        width=0.75,
+        which="minor",
+        bottom=True,
+        top=True,
+        left=True,
+        right=True,
+    )
+
+
+fig, ax1 = plt.subplots(figsize=(12, 8))
+nclize_axis(ax1)
+ax1.set_xlabel(ds.time.long_name, fontsize=24)
+ax1.set_ylabel(f"{ds.T.long_name} [solid]", fontsize=24)
+ax1.plot(ds.time, ds.T, color="blue", linestyle="-", linewidth=2.0)
+ax1.tick_params(axis="both", labelsize=20)
+ax1.set_xlim(xmin=1970, xmax=1973)
+ax1.set_ylim(ymin=0.0, ymax=16.0)
+ax1.set_yticks(np.arange(0, 17, 3))
+
+
+ax2 = ax1.twinx()
+nclize_axis(ax2)
+
+
+# we already handled the x-label with ax1
+
+ax2.set_ylabel(f"{ds.P.long_name} [dash]", fontsize=24)
+ax2.plot(ds.time, ds.P, color="red", linestyle="--", linewidth=2.0, dashes=[6.5, 3.7])
+ax2.tick_params(axis="both", labelsize=20)
+ax2.set_ylim(ymin=1008, ymax=1024.0)
+ax2.set_yticks(np.arange(1008, 1025, 3))
+
+
+plt.title("Curves Offset", fontsize=24, fontweight="bold", y=1.05)
+
+fig.tight_layout()
+plt.show()