Reputation: 20101
I'm reading a parquet file that has the following schema:
df.printSchema()
root
|-- time: integer (nullable = true)
|-- amountRange: integer (nullable = true)
|-- label: integer (nullable = true)
|-- pcaVector: vector (nullable = true)
Now I want to test Pyspark structured streaming and I want to use the same parquet files. The closest schema that I was able to create was using ArrayType, but it doesn't work:
schema = StructType(
[
StructField('time', IntegerType()),
StructField('amountRange', IntegerType()),
StructField('label', IntegerType()),
StructField('pcaVector', ArrayType(FloatType()))
]
)
df_stream = spark.readStream\
.format("parquet")\
.schema(schema)\
.load("/home/user/test_arch/data/fraud/")
Caused by: java.lang.ClassCastException: Expected instance of group converter but got "org.apache.spark.sql.execution.datasources.parquet.ParquetPrimitiveConverter"
at org.apache.parquet.io.api.Converter.asGroupConverter(Converter.java:37)
at org.apache.spark.sql.execution.datasources.parquet.ParquetRowConverter$RepeatedGroupConverter.<init>(ParquetRowConverter.scala:659)
at org.apache.spark.sql.execution.datasources.parquet.ParquetRowConverter.org$apache$spark$sql$execution$datasources$parquet$ParquetRowConverter$$newConverter(ParquetRowConverter.scala:308)
How can I create a schema with VectorType, that seems to exist only for Scala, for the StructType in Pyspark?
Upvotes: 7
Views: 4364
Reputation: 96
The type is VectorUDT
from pyspark.ml.linalg import VectorUDT
StructField('pcaVector', VectorUDT())
Upvotes: 8