Improve readability of slice notation

README.md

@@ -72,7 +72,7 @@ lat = -33.75
 lon = 151.25
 
 # Create temporary dataframe at specific location
-df1 = df.loc[lat, lon]
+df1 = df.loc[(lat, lon), :]
 
 # Plot time series
 fig, ax = plt.subplots(1, 1, figsize=(6, 4))
@@ -112,14 +112,11 @@ dates = df.index.get_level_values('time').unique()
 fig, ax = plt.subplots(3, 4)
 
 for i, date in enumerate(dates):
-    # Get temporary dataframe with only one date
-    df1 = df[df.index.get_level_values('time') == date]
-
-    # Remove date from multi-index
-    df1.index = df1.index.droplevel(-1)
+    # Get temporary dataframe with only one date ('slice(None)' is ':')
+    df1 = df.loc[(slice(None), slice(None), date), :]
 
     # Split multi-index so that rows=latitude and columns=longitude
-    grid = df1.unstack()
+    grid = df1.unstack().unstack()
 
     # Plot colour map for current month
     a = ax.ravel()[i]