Spark Python Pyspark如何使用一系列字典和嵌入式字典展平列(sparknlp注释器输出)
我试图从sparknlp中提取输出(使用预先训练好的管道“explain\u document\u dl”)。我花了很多时间寻找方法(UDF、explode等),但无法找到可行的解决方案。假设我想从Spark Python Pyspark如何使用一系列字典和嵌入式字典展平列(sparknlp注释器输出),python,scala,apache-spark,pyspark,johnsnowlabs-spark-nlp,Python,Scala,Apache Spark,Pyspark,Johnsnowlabs Spark Nlp,我试图从sparknlp中提取输出(使用预先训练好的管道“explain\u document\u dl”)。我花了很多时间寻找方法(UDF、explode等),但无法找到可行的解决方案。假设我想从实体列中获取结果和元数据下的提取值。在该列中有一个包含多个字典的数组 当我使用df.withColumn(“entity\u name”,explode(“entities.result”))时,只提取第一个字典中的值 “实体”列的内容是词典列表 试图提供一个可复制的示例/重新创建数据帧(感谢下面@j
实体
列中获取结果
和元数据
下的提取值。在该列中有一个包含多个字典的数组
当我使用df.withColumn(“entity\u name”,explode(“entities.result”))
时,只提取第一个字典中的值
“实体”列的内容是词典列表
试图提供一个可复制的示例/重新创建数据帧(感谢下面@jonathan提供的建议):
#以一个单元格的内容为例:
d=[{“注释类型”:“块”,“开始”:2740,“结束”:2747,“结果”:“•能力”,“元数据”:{“实体”:“组织”,“句子”:“8”,“块”:“22”},“嵌入”:[],“句子嵌入”:[]},{“注释类型”:“块”,“开始”:2740,“结束”:2747,“结果”:“联邦快递”,“元数据”:{“实体”:“组织”,“句子”:“8”,“块”:“22”},“嵌入”:[],“句子嵌入”:[]]
从pyspark.sql.types导入StructType、StructField、StringType
从数组导入数组
schema=StructType([StructField('annotatorType',StringType(),True),
StructField('begin',IntegerType(),True),
StructField('end',IntegerType(),True),
StructField('result',StringType(),True),
StructField('句子',StringType(),True),
StructField('chunk',StringType(),True),
StructField('metadata',StructType((StructField('entity',StringType(),True)),
StructField('句子',StringType(),True),
StructField('chunk',StringType(),True)
))是的,
StructField('embeddings',StringType(),True),
StructField('句子嵌入',StringType(),True)
]
)
df=spark.createDataFrame(d,schema=schema)
df.show()
在这种情况下,如果是一个字典列表,它将起作用:
+-------------+-----+----+--------+--------+-----+------------+----------+-------------------+
|annotatorType|begin| end| result|sentence|chunk| metadata|embeddings|sentence_embeddings|
+-------------+-----+----+--------+--------+-----+------------+----------+-------------------+
| chunk| 2740|2747|•Ability| null| null|[ORG, 8, 22]| []| []|
| chunk| 2740|2747| Fedex| null| null|[ORG, 8, 22]| []| []|
+-------------+-----+----+--------+--------+-----+------------+----------+-------------------+
但我一直在研究如何将其应用于一个列,该列包含一些带有多个字典数组的单元格(因此原始单元格有多行)
我尝试将相同的模式应用于entities
列,并且必须首先将该列转换为json
ent1 = ent1.withColumn("entities2", to_json("entities"))
它适用于具有1个字典数组的单元格,但为具有多个字典数组的单元格(第4行)提供null
:
ent1.withColumn(“entities2”,来自_json(“entities2”,schema)).select(“entities2.*).show()
+-------------+-----+----+------+--------+-----+------------+----------+-------------------+
|注释类型|开始|结束|结果|句子|块|元数据|嵌入|句子|嵌入|
+-------------+-----+----+------+--------+-----+------------+----------+-------------------+
|chunk | 166 | 169 | Lyft | null | null |[MISC,0,0]|[]|
|chunk | 11 | 14 | Lyft | null | null |[MISC,0,0]|[]|
|chunk | 52 | 55 | Lyft | null | null |[MISC,1,0]|[]|
|空|空|空|空|空|空|空|空|空|
+-------------+-----+----+------+--------+-----+------------+----------+-------------------+
所需输出为
+-------------+-----+----+----------------+------------------------+----------+-------------------+
|annotatorType|begin| end| result | metadata |embeddings|sentence_embeddings|
+-------------+-----+----+----------------+------------------------+----------+-------------------+
| chunk| 166| 169|Lyft |[MISC] | []| []|
| chunk| 11| 14|Lyft |[MISC] | []| []|
| chunk| 52| 55|Lyft. |[MISC] | []| []|
| chunk| [..]|[..]|[Lyft,Lyft, |[MISC,MISC,MISC, | []| []|
| | | |FedEx Ground..] |ORG,LOC,ORG,ORG,ORG,ORG]| | |
+-------------+-----+----+----------------+------------------------+----------+-------------------+
我还尝试为每一行转换为json,但我失去了对原始行的跟踪,并获得了flatted son:
new_df = sqlContext.read.json(ent2.rdd.map(lambda r: r.entities2))
new_df.show()
+-------------+-----+----------+----+------------+----------------+-------------------+
|annotatorType|begin|embeddings| end| metadata| result|sentence_embeddings|
+-------------+-----+----------+----+------------+----------------+-------------------+
| chunk| 166| []| 169|[0, MISC, 0]| Lyft| []|
| chunk| 11| []| 14|[0, MISC, 0]| Lyft| []|
| chunk| 52| []| 55|[0, MISC, 1]| Lyft| []|
| chunk| 0| []| 11| [0, ORG, 0]| FedEx Ground| []|
| chunk| 717| []| 720| [1, LOC, 4]| Dock| []|
| chunk| 811| []| 816| [2, ORG, 5]| Parcel| []|
| chunk| 1080| []|1095| [3, ORG, 6]|Parcel Assistant| []|
| chunk| 1102| []|1108| [4, ORG, 7]| • Daily| []|
| chunk| 1408| []|1417| [5, ORG, 8]| Assistants| []|
+-------------+-----+----------+----+------------+----------------+-------------------+
我尝试应用UDF遍历“实体”中的数组列表:
def展平(我的命令):
d_结果=默认DICT(列表)
对于我的遗嘱中的sub:
val=sub['result']
d_结果[“结果”]。追加(val)
返回d_结果[“结果”]
ent=ent.withColumn('result',展平(df.entities))
TypeError:列不可编辑
我发现这篇文章与我的问题非常相似,但在将列entities
转换为json之后,我仍然无法用那篇文章中提供的解决方案来解决它
感谢您的帮助!!理想的python解决方案,但scala中的示例也很有用 获取
null
的原因是schema
变量不能准确表示作为数据传入的词典列表
from pyspark.shell import *
from pyspark.sql.types import *
schema = StructType([StructField('result', StringType(), True),
StructField('metadata', StructType((StructField('entity', StringType(), True),
StructField('sentence', StringType(), True),
StructField('chunk', StringType(), True))), True)])
df = spark.createDataFrame(d1, schema=schema)
df.show()
如果您喜欢定制的解决方案,可以尝试纯python/pandas方法
import pandas as pd
from pyspark.shell import *
result = []
metadata_entity = []
for row in d1:
result.append(row.get('result'))
metadata_entity.append(row.get('metadata').get('entity'))
schema = {'result': [result], 'metadata.entity': [metadata_entity]}
pandas_df = pd.DataFrame(schema)
df = spark.createDataFrame(pandas_df)
df.show()
# specific columns
df.select('result','metadata.entity').show()
编辑
在阅读了您一直在尝试的所有方法之后,我认为,sc.parallelize
仍然适用于相当复杂的情况。我没有你的原始变量,但我可以OCR你的图像并从那里获取它——尽管不再有课堂老师或教学价值观。希望这一切都有用
您始终可以使用所需的结构及其模式创建模拟数据帧
对于具有嵌套数据类型的复杂情况,可以使用SparkContext并读取生成的JSON格式
import itertools
from pyspark.shell import *
from pyspark.sql.functions import *
from pyspark.sql.types import *
# assume two lists in two dictionary keys to make four cells
# since I don't have but entities2, I can just replicate it
sample = {
'single_list': [{'annotatorType': 'chunk', 'begin': '166', 'end': '169', 'result': 'Lyft',
'metadata': {'entity': 'MISC', 'sentence': '0', 'chunk': '0'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '11', 'end': '14', 'result': 'Lyft',
'metadata': {'entity': 'MISC', 'sentence': '0', 'chunk': '0'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '52', 'end': '55', 'result': 'Lyft',
'metadata': {'entity': 'MISC', 'sentence': '1', 'chunk': '0'}, 'embeddings': [],
'sentence_embeddings': []}],
'frankenstein': [
{'annotatorType': 'chunk', 'begin': '0', 'end': '11', 'result': 'FedEx Ground',
'metadata': {'entity': 'ORG', 'sentence': '0', 'chunk': '0'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '717', 'end': '720', 'result': 'Dock',
'metadata': {'entity': 'LOC', 'sentence': '4', 'chunk': '1'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '811', 'end': '816', 'result': 'Parcel',
'metadata': {'entity': 'ORG', 'sentence': '5', 'chunk': '2'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '1080', 'end': '1095', 'result': 'Parcel Assistant',
'metadata': {'entity': 'ORG', 'sentence': '6', 'chunk': '3'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '1102', 'end': '1108', 'result': '* Daily',
'metadata': {'entity': 'ORG', 'sentence': '7', 'chunk': '4'}, 'embeddings': [],
'sentence_embeddings': []},
{'annotatorType': 'chunk', 'begin': '1408', 'end': '1417', 'result': 'Assistants',
'metadata': {'entity': 'ORG', 'sentence': '8', 'chunk': '5'}, 'embeddings': [],
'sentence_embeddings': []}]
}
# since they are structurally different, get two dataframes
df_single_list = spark.read.json(sc.parallelize(sample.get('single_list')))
df_frankenstein = spark.read.json(sc.parallelize(sample.get('frankenstein')))
# print better the table first border
print('\n')
# list to create a dataframe schema
annotatorType = []
begin = []
embeddings = []
end = []
metadata = []
result = []
sentence_embeddings = []
# PEP8 here to have an UDF instead of lambdas
# probably a dictionary with actions to avoid IF statements
function_metadata = lambda x: [x.entity]
for k, i in enumerate(df_frankenstein.columns):
if i == 'annotatorType':
annotatorType.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
if i == 'begin':
begin.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
if i == 'embeddings':
embeddings.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
if i == 'end':
end.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
if i == 'metadata':
_temp = list(map(function_metadata, df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect()))
metadata.append(list(itertools.chain.from_iterable(_temp)))
if i == 'result':
result.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
if i == 'sentence_embeddings':
sentence_embeddings.append(df_frankenstein.select(i).rdd.flatMap(lambda x: x).collect())
# headers
annotatorType_header = 'annotatorType'
begin_header = 'begin'
embeddings_header = 'embeddings'
end_header = 'end'
metadata_header = 'metadata'
result_header = 'result'
sentence_embeddings_header = 'sentence_embeddings'
metadata_entity_header = 'metadata.entity'
frankenstein_schema = StructType(
[StructField(annotatorType_header, ArrayType(StringType())),
StructField(begin_header, ArrayType(StringType())),
StructField(embeddings_header, ArrayType(StringType())),
StructField(end_header, ArrayType(StringType())),
StructField(metadata_header, ArrayType(StringType())),
StructField(result_header, ArrayType(StringType())),
StructField(sentence_embeddings_header, ArrayType(StringType()))
])
# list of lists of lists of lists of ... lists
frankenstein_list = [[annotatorType, begin, embeddings, end, metadata, result, sentence_embeddings]]
df_frankenstein = spark.createDataFrame(frankenstein_list, schema=frankenstein_schema)
print(df_single_list.schema)
print(df_frankenstein.schema)
# let's see how it is
df_single_list.select(
annotatorType_header,
begin_header,
end_header,
result_header,
array(metadata_entity_header),
embeddings_header,
sentence_embeddings_header).show()
# let's see again
df_frankenstein.select(
annotatorType_header,
begin_header,
end_header,
result_header,
metadata_header,
embeddings_header,
sentence_embeddings_header).show()
输出:
StructType(List(StructField(annotatorType,StringType,true),StructField(begin,StringType,true),StructField(embeddings,ArrayType(StringType,true),true),StructField(end,StringType,true),StructField(metadata,StructType(List(StructField(chunk,StringType,true),StructField(entity,StringType,true),StructField(sentence,StringType,true))),true),StructField(result,StringType,true),StructField(sentence_embeddings,ArrayType(StringType,true),true)))
StructType(List(StructField(annotatorType,ArrayType(StringType,true),true),StructField(begin,ArrayType(StringType,true),true),StructField(embeddings,ArrayType(StringType,true),true),StructField(end,ArrayType(StringType,true),true),StructField(metadata,ArrayType(StringType,true),true),StructField(result,ArrayType(StringType,true),true),StructField(sentence_embeddings,ArrayType(StringType,true),true)))
+-------------+-----+---+------+----------------------+----------+-------------------+
|annotatorType|begin|end|result|array(metadata.entity)|embeddings|sentence_embeddings|
+-------------+-----+---+------+----------------------+----------+-------------------+
| chunk| 166|169| Lyft| [MISC]| []| []|
| chunk| 11| 14| Lyft| [MISC]| []| []|
| chunk| 52| 55| Lyft| [MISC]| []| []|
+-------------+-----+---+------+----------------------+----------+-------------------+
+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+
| annotatorType| begin| end| result| metadata| embeddings| sentence_embeddings|
+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+
|[[chunk, chunk, c...|[[0, 717, 811, 10...|[[11, 720, 816, 1...|[[FedEx Ground, D...|[[ORG, LOC, ORG, ...|[[[], [], [], [],...|[[[], [], [], [],...|
+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+--------------------+
您必须分别从每个数据帧中进行选择,因为它们的数据类型不同,但内容已经准备好(如果我从输出中了解您的需求)可以使用
(°)请阅读并回答相应的问题。Spark NLP使用了很多自定义模式,了解上游步骤在这里是至关重要的。我尝试重新创建Spark数据帧,但我只能得到NULL。我不熟悉spark dataframe,所以可能缺少一些东西。我提供了模式作为参考。谢谢乔纳森!我还发现我可以使用json_schema=spark.read.json(df.rdd.map)(lambda row:row.entities2