修改无效
nodes = pd.read_csv("pre_only_num.csv",header =None)
for index,row in nodes.iterrows():
#print(row[0])
row[0] = -1
直接在原处修改无效
for index,row in nodes.iterrows():
oid = int(row[0])
nodes.iat[index,0] = self.idmap[oid]# !!!
