Fix formatting

power_plot.py

@@ -14,8 +14,7 @@ import matplotlib
 import matplotlib.pyplot as plt
 from matplotlib.widgets import Button, CheckButtons
 from matplotlib.collections import LineCollection
-from matplotlib.ticker import FuncFormatter
-from matplotlib.dates import HourLocator, date2num, num2date, AutoDateLocator
+from matplotlib.dates import date2num, num2date, AutoDateFormatter
 from matplotlib.figure import Figure
 
 from PyQt5.QtWidgets import QApplication, QMainWindow, QVBoxLayout, QWidget, QComboBox
@@ -42,10 +41,13 @@ class PowerPlot:
         self.ax.set_xlabel("Time (UTC)")
         self.ax.set_ylabel(yname)
         self.ax.xaxis_date()
+
+        formatter = AutoDateFormatter(self.ax.xaxis.get_major_locator())
+        formatter.scaled[1 / (24 * 60)] = "%H:%M"
+
+        self.ax.xaxis.set_major_formatter(formatter)
+
         self.min, self.max = None, None
-        self.ax.xaxis.set_major_formatter(
-            FuncFormatter(lambda x, pos: f"{num2date(x):%H:%M}")
-        )
         fig.suptitle(yname, fontsize=16)
         fig.tight_layout()
         (self.totalplot,) = self.ax.plot([], [], ".", color="blue")