小编pro*_*ray的帖子

我sudo pip install -U nltk按照nltk文档的建议做了.但是,我得到以下输出:

Collecting nltk
  Downloading nltk-3.0.5.tar.gz (1.0MB)
    100% |????????????????????????????????| 1.0MB 516kB/s 
Collecting six>=1.9.0 (from nltk)
  Downloading six-1.9.0-py2.py3-none-any.whl
Installing collected packages: six, nltk
  Found existing installation: six 1.4.1
    DEPRECATION: Uninstalling a distutils installed project (six) has been deprecated and will be removed in a future version. This is due to the fact that uninstalling a distutils project will only partially uninstall the project.
    Uninstalling six-1.4.1:
Exception:
Traceback (most recent call last):
  File "/Library/Python/2.7/site-packages/pip/basecommand.py", line 211, in …

我创建了一个表

create 'tablename', 'columnfamily1'

现在可以添加另一个列系列'columnfamily2'吗？方法是什么？

我理解Group没有使用多个元组,因此我们在PIG中使用了COGROUP.但是,今天检查GROUP命令对我有用.我使用的是PIG-0.12.0.我的命令和输出如下.

grunt> grpvar = GROUP C by $2, B by $2;
grunt> cogrpvar = COGROUP C by $2, B by $2;
grunt> describe grpvar;

grpvar: {group: chararray,C: {(pid: int,pname: chararray,drug: chararray,gender: chararray,tot_amt: int)},B: {(pid: int,pname: chararray,drug: chararray,gender: chararray,tot_amt: int)}}

grunt> describe cogrpvar;

cogrpvar: {group: chararray,C: {(pid: int,pname: chararray,drug: chararray,gender: chararray,tot_amt: int)},B: {(pid: int,pname: chararray,drug: chararray,gender: chararray,tot_amt: int)}}

GROUP预计会像这样工作吗？GROUP和COGROUP有什么区别？

src = Folder1/Folder2/file1
（编辑：Folder1 也有其​​他文件和文件夹）

dst = Folder3

复制文件后，我想要
Folder3/Folder1/Folder2/file1

我认为shutil.copy 不会重新创建文件夹并且shutil.copytree仅用于文件夹（编辑：如果没有其他文件，我可以直接复制文件夹）。

该列在一行中多次使用分隔符，因此split并不那么简单。
拆分时，在这种情况下只需考虑第一个分隔符出现。

截至目前，我正在这样做。

不过我觉得还有更好的解决办法吗？

testdf= spark.createDataFrame([("Dog", "meat,bread,milk"), ("Cat", "mouse,fish")],["Animal", "Food"])

testdf.show()

+------+---------------+
|Animal|           Food|
+------+---------------+
|   Dog|meat,bread,milk|
|   Cat|     mouse,fish|
+------+---------------+

testdf.withColumn("Food1", split(col("Food"), ",").getItem(0))\
        .withColumn("Food2",expr("regexp_replace(Food, Food1, '')"))\
        .withColumn("Food2",expr("substring(Food2, 2)")).show()

+------+---------------+-----+----------+
|Animal|           Food|Food1|     Food2|
+------+---------------+-----+----------+
|   Dog|meat,bread,milk| meat|bread,milk|
|   Cat|     mouse,fish|mouse|      fish|
+------+---------------+-----+----------+