解决方法：rm -r XXX-r：将参数中列出的全部目录和子目录都递归地删除。

错误：在去除dataframe中重复的列名时遇到的无法删除列名的错误，检查填写了axis还是报错KeyError: "['Fwd Header Length'] not found in axis"原因：列名输错，列名前面有空格解决方法：把列名写对参考资料：https://blog.csdn.net/qq_45797116/article/details/110424636的评论区...

错误：RuntimeWarning: invalid value encountered in sqrt result = getattr(ufunc, method)(*inputs, **kwargs错误原因：由于在计算sqrt 的矩阵里面出现负数，所以我们才会开根号报错解决方法：np.abs()，开根号前取绝对值参考资料:https://blog.csdn.net/weixin_449916

问题：查看elasticsearch日志$ cat es-cluster.log出现Caused by: java.lang.IllegalStateException: failed to obtain node locks, tried [[/home/cyj/cluster/elasticsearch-5.6.2/data/es-cluster]] with lock id [0]; may

问题：/usr/local/mongodb/bin/mongod: error while loading shared libraries: libssl.so.10: cannot open shared object file: No such file or directory解决办法：通过命令ldd /usr/local/mongodb/bin/mongod来查看./mongod还需要哪