[Python] Clear and repopulate Matplotlib in PyQt5?

I would like to update a graph with new data after a refresh button is pressed. To achieve this, I would like to delete or clear the existing graph and then recreate it. I am using matplotlib within my PyQt5 GUI window. More specifically, the parent of my matplotlib graph is a PyQt5 GroupBox.

This is the code that I use to construct the plot:

def initEventGraph(self, parent, numDays=7):
self.canvas = FigureCanvas(plt.Figure(figsize=(6.31,4.75), dpi=80))
self.canvas.setParent(parent)
self.canvas.move(10,20)

self.ax = self.canvas.figure.subplots()

FigureCanvas.setSizePolicy(self,
QSizePolicy.Expanding,
QSizePolicy.Expanding)
FigureCanvas.updateGeometry(self)

self.plot(num_days=numDays)


This is the code that I use to apply the data to the plot:

def plot(self,num_days):
current_time = datetime.datetime.now()
events = self.findXDayOldEvents(days=num_days, current_time=current_time)
sorted_events = self.sortEventList(events)

for event_name, entries in sorted_events.items():
x_axis = entries["Time"]
y_axis = entries["Channel"]
color = entries["Color"]
self.ax.scatter(x_axis, y_axis,color=color, label=event_name)
self.ax.tick_params(labelrotation=15)
self.ax.legend()
self.ax.set_ylabel("Channel")
self.ax.grid()


I have tried several different approaches involving clear(), clf(), and cla(). In addition to other various approaches, I have not been able to clear or delete the existing plot.

What I would like is to clear my existing plot and then just call my function plot() again. How is this possible?

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