fixed a bug with wrong LaTeX input

mathbot/rendering.py

@@ -20,21 +20,34 @@ from io import BytesIO
 import matplotlib
 matplotlib.use("Agg")
 import matplotlib.pyplot as plt
+import importlib
 
 
 def get_png(tex):
+	importlib.reload(plt)
 	buf = BytesIO()
 
-	plt.text(0, 0.6, r"$%s$" % tex, fontsize = 50)
-	fig = plt.gca()                                                                 
-	fig.axes.get_xaxis().set_visible(False)                                         
-	fig.axes.get_yaxis().set_visible(False)
+	exc = None
 
-	plt.savefig(buf)
+	try:
+		plt.subplot()
 
-	buf.seek(0)
+		plt.text(0, 0.6, r"$%s$" % tex, fontsize = 50)
+		fig = plt.gca()                                                                 
+		fig.axes.get_xaxis().set_visible(False)                                         
+		fig.axes.get_yaxis().set_visible(False)
 
-	plt.clf()
+		plt.savefig(buf)
+
+		buf.seek(0)
+
+	except Exception as e:
+		exc = e
+	finally:
+		plt.clf()
+
+	if(exc):
+		raise exc
 
 	return buf