ZeroDivisionError: division by zero

[s5377689]

ZeroDivisionError Traceback (most recent call last)
in
69 # Compute training statistics
70 epoch_loss = float(np.mean(epoch_loss))
---> 71 ASR_TOG = score_adv / num_rois
72 ASR_Rand = score_rand / num_rois
73

ZeroDivisionError: division by zero

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If some images fail to detect objects

Is this modification correct?

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Compute training statistics

epoch_loss = float(np.mean(epoch_loss))
###########################################code i added

+     if num_rois > 0:
+          ASR_TOG = score_adv / num_rois
+         ASR_Rand = score_rand / num_rois
+     else:
+         ASR_TOG = 0.0
+         ASR_Rand = 0.0
    ###########################################code i added
    ASR_TOG = score_adv / num_rois
    ASR_Rand = score_rand / num_rois