如何使用 dict 创建新的 DataFrame [英] How to create new DataFrame with dict

问题描述

我有一个 dict，比如:

cMap = {"k1" : "v1", "k2" : "v1", "k3" : "v2", "k4" : "v2"}

和一个 DataFrame A，例如:

and one DataFrame A, like:

+---+
|key|
+----
| k1|
| k2|
| k3|
| k4|
+---+

使用代码创建上面的 DataFame:

to create the DataFame above with code:

data = [('k1'),
    ('k2'),
    ('k3'),
    ('k4')]
A = spark.createDataFrame(data, ['key'])

我想获得新的 DataFrame，例如:

I want to get the new DataFrame, like:

+---+----------+----------+
|key|   v1     |    v2    |
+---+----------+----------+
| k1|true      |false     |
| k2|true      |false     |
| k3|false     |true      |
| k4|false     |true      |
+---+----------+----------+

希望得到一些建议，谢谢！

I wish to get some suggestions, thanks!

推荐答案

感谢大家的建议，我想出了解决pivot问题的另一种方法，代码是:

Thanks everyone for some suggestions, I figured out the other way to resolve my problem with pivot, the code is:

cMap = {"k1" : "v1", "k2" : "v1", "k3" : "v2", "k4" : "v2"}
a_cMap = [(k,)+(v,) for k,v in cMap.items()] 
data = spark.createDataFrame(a_cMap, ['key','val'])

from pyspark.sql.functions import count
data = data.groupBy('key').pivot('val').agg(count('val'))
data.show()

+---+----+----+
|key|  v1|  v2|
+---+----+----+
| k2|   1|null|
| k4|null|   1|
| k1|   1|null|
| k3|null|   1|
+---+----+----+

data = data.na.fill(0)
data.show()

+---+---+---+
|key| v1| v2|
+---+---+---+
| k2|  1|  0|
| k4|  0|  1|
| k1|  1|  0|
| k3|  0|  1|
+---+---+---+

keys = spark.createDataFrame([('k1','2'),('k2','3'),('k3','4'),('k4','5'),('k5','6')], ["key",'temp'])

newDF = keys.join(data,'key')
newDF.show()
+---+----+---+---+
|key|temp| v1| v2|
+---+----+---+---+
| k2|   3|  1|  0|
| k4|   5|  0|  1|
| k1|   2|  1|  0|
| k3|   4|  0|  1|
+---+----+---+---+

但是，我无法将 1 转换为 true，将 0 转换为 false.

But, I can't convert 1 to true, 0 to false.

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