RuntimeWarning: invalid value encountered in divide

[dongfeicui]

I encountered the following error, will this affect the training? I got very bad results.
/mnt/4t_disk/sxq/CRGNet4/utils/tools.py:98: RuntimeWarning: invalid value encountered in divide
acc_cls = np.diag(hist) / hist.sum(axis=1)
/mnt/4t_disk/sxq/CRGNet4/utils/tools.py: 100 : RuntimeWarning: invalid value encountered in divide
iu = np.diag(hist) / (hist.sum(axis=1) + hist.sum(axis=0) - np.diag(hist))
VaihingenSeg_log.txt