Does anyone have experience using pandas UDFs on a local pyspark session running on Windows? I've used them on linux with good results, but I've been unsuccessful on my Windows machine.
Environment:
python==3.7
pyarrow==0.15
pyspark==2.3.4
pandas==0.24
java version "1.8.0_74"
Sample script:
from pyspark.sql.functions import pandas_udf, PandasUDFType
from pyspark.sql import SparkSession
spark = SparkSession.builder.master("local").getOrCreate()
spark.conf.set("spark.sql.execution.arrow.enabled", "true")
spark.conf.set("spark.sql.execution.arrow.fallback.enabled", "false")
df = spark.createDataFrame(
[(1, 1.0), (1, 2.0), (2, 3.0), (2, 5.0), (2, 10.0)],
("id", "v"))
#pandas_udf("id long, v double", PandasUDFType.GROUPED_MAP)
def subtract_mean(pdf):
# pdf is a pandas.DataFrame
v = pdf.v
return pdf.assign(v=v - v.mean())
out_df = df.groupby("id").apply(subtract_mean).toPandas()
print(out_df.head())
# +---+----+
# | id| v|
# +---+----+
# | 1|-0.5|
# | 1| 0.5|
# | 2|-3.0|
# | 2|-1.0|
# | 2| 4.0|
# +---+----+
After running for a loooong time (splits the toPandas stage into 200 tasks each taking over a second) it returns an error like this:
Traceback (most recent call last):
File "C:\miniconda3\envs\pandas_udf\lib\site-packages\pyspark\sql\dataframe.py", line 1953, in toPandas
tables = self._collectAsArrow()
File "C:\miniconda3\envs\pandas_udf\lib\site-packages\pyspark\sql\dataframe.py", line 2004, in _collectAsArrow
sock_info = self._jdf.collectAsArrowToPython()
File "C:\miniconda3\envs\pandas_udf\lib\site-packages\py4j\java_gateway.py", line 1257, in __call__
answer, self.gateway_client, self.target_id, self.name)
File "C:\miniconda3\envs\pandas_udf\lib\site-packages\pyspark\sql\utils.py", line 63, in deco
return f(*a, **kw)
File "C:\miniconda3\envs\pandas_udf\lib\site-packages\py4j\protocol.py", line 328, in get_return_value
format(target_id, ".", name), value)
py4j.protocol.Py4JJavaError: An error occurred while calling o62.collectAsArrowToPython.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 69 in stage 3.0 failed 1 times, most recent failure: Lost task 69.0 in stage 3.0 (TID 201, localhost, executor driver): java.lang.IllegalArgumentException
at java.nio.ByteBuffer.allocate(Unknown Source)
at org.apache.arrow.vector.ipc.message.MessageChannelReader.readNextMessage(MessageChannelReader.java:64)
at org.apache.arrow.vector.ipc.message.MessageSerializer.deserializeSchema(MessageSerializer.java:104)
at org.apache.arrow.vector.ipc.ArrowStreamReader.readSchema(ArrowStreamReader.java:128)
at org.apache.arrow.vector.ipc.ArrowReader.initialize(ArrowReader.java:181)
at org.apache.arrow.vector.ipc.ArrowReader.ensureInitialized(ArrowReader.java:172)
at org.apache.arrow.vector.ipc.ArrowReader.getVectorSchemaRoot(ArrowReader.java:65)
at org.apache.spark.sql.execution.python.ArrowPythonRunner$$anon$1.read(ArrowPythonRunner.scala:161)
at org.apache.spark.sql.execution.python.ArrowPythonRunner$$anon$1.read(ArrowPythonRunner.scala:121)
at org.apache.spark.api.python.BasePythonRunner$ReaderIterator.hasNext(PythonRunner.scala:290)
at org.apache.spark.InterruptibleIterator.hasNext(InterruptibleIterator.scala:37)
at scala.collection.Iterator$$anon$12.hasNext(Iterator.scala:439)
at scala.collection.Iterator$$anon$11.hasNext(Iterator.scala:408)
at org.apache.spark.sql.execution.arrow.ArrowConverters$$anon$2.hasNext(ArrowConverters.scala:96)
at scala.collection.Iterator$class.foreach(Iterator.scala:893)
at org.apache.spark.sql.execution.arrow.ArrowConverters$$anon$2.foreach(ArrowConverters.scala:94)
at scala.collection.generic.Growable$class.$plus$plus$eq(Growable.scala:59)
at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:104)
at scala.collection.mutable.ArrayBuffer.$plus$plus$eq(ArrayBuffer.scala:48)
at scala.collection.TraversableOnce$class.to(TraversableOnce.scala:310)
at org.apache.spark.sql.execution.arrow.ArrowConverters$$anon$2.to(ArrowConverters.scala:94)
at scala.collection.TraversableOnce$class.toBuffer(TraversableOnce.scala:302)
at org.apache.spark.sql.execution.arrow.ArrowConverters$$anon$2.toBuffer(ArrowConverters.scala:94)
at scala.collection.TraversableOnce$class.toArray(TraversableOnce.scala:289)
at org.apache.spark.sql.execution.arrow.ArrowConverters$$anon$2.toArray(ArrowConverters.scala:94)
at org.apache.spark.rdd.RDD$$anonfun$collect$1$$anonfun$12.apply(RDD.scala:945)
at org.apache.spark.rdd.RDD$$anonfun$collect$1$$anonfun$12.apply(RDD.scala:945)
at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:2074)
at org.apache.spark.SparkContext$$anonfun$runJob$5.apply(SparkContext.scala:2074)
at org.apache.spark.scheduler.ResultTask.runTask(ResultTask.scala:87)
at org.apache.spark.scheduler.Task.run(Task.scala:109)
at org.apache.spark.executor.Executor$TaskRunner.run(Executor.scala:345)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Your java.lang.IllegalArgumentException in pandas_udf has to do with pyarrow version, not with OS environment. See this issue for details.
You have two routs of action:
Downgrade pyarrow to v.0.14, or
Add environment variable ARROW_PRE_0_15_IPC_FORMAT=1 to SPARK_HOME/conf/spark-env.sh
On Windows, you'll need to have a spark-env.cmd file in the conf directory: set ARROW_PRE_0_15_IPC_FORMAT=1, as suggested by Jonathan Taws
Addendum to the answer of Sergey:
if you prefer to build your own sparkSession in python and not change your config files, you'll need to set both spark.yarn.appMasterEnv.ARROW_PRE_0_15_IPC_FORMAT and the environment variable of the local executor spark.executorEnv.ARROW_PRE_0_15_IPC_FORMAT
spark_session = SparkSession.builder \
.master("yarn") \
.config('spark.yarn.appMasterEnv.ARROW_PRE_0_15_IPC_FORMAT',1)\
.config('spark.executorEnv.ARROW_PRE_0_15_IPC_FORMAT',1)
spark = spark_session.getOrCreate()
Hope this helps!
Related
I am trying to write a pandas dataframe to the local file system in azure databricks:
import pandas as pd
url = 'https://www.stats.govt.nz/assets/Uploads/Business-price-indexes/Business-price-indexes-March-2019-quarter/Download-data/business-price-indexes-march-2019-quarter-csv.csv'
data = pd.read_csv(url)
with pd.ExcelWriter(r'/dbfs/tmp/export.xlsx', engine="openpyxl") as writer:
data.to_excel(writer)
Then I get the following error message:
OSError: [Errno 95] Operation not supported
--------------------------------------------------------------------------- OSError Traceback (most recent call
last) in
3 data = pd.read_csv(url)
4 with pd.ExcelWriter(r'/dbfs/tmp/export.xlsx', engine="openpyxl") as writer:
----> 5 data.to_excel(writer)
/databricks/python/lib/python3.8/site-packages/pandas/io/excel/_base.py
in exit(self, exc_type, exc_value, traceback)
892
893 def exit(self, exc_type, exc_value, traceback):
--> 894 self.close()
895
896 def close(self):
/databricks/python/lib/python3.8/site-packages/pandas/io/excel/_base.py
in close(self)
896 def close(self):
897 """synonym for save, to make it more file-like"""
--> 898 content = self.save()
899 self.handles.close()
900 return content
I read in this post some limitations for mounted file systems: Pandas: Write to Excel not working in Databricks
But if I got it right, the solution is to write to the local workspace file system, which is exactly what is not working for me.
My user is workspace admin and I am using a standard cluster with 10.4 Runtime.
I also verified I can write csv file to the same location using pd.to_csv
What could be missing.
Databricks has a drawback that does not allow random write operations into DBFS which is indicated in the SO thread you are referring to.
So, a workaround for this would be to write the file to local file system (file:/) and then move to the required location inside DBFS. You can use the following code:
import pandas as pd
url = 'https://www.stats.govt.nz/assets/Uploads/Business-price-indexes/Business-price-indexes-March-2019-quarter/Download-data/business-price-indexes-march-2019-quarter-csv.csv'
data = pd.read_csv(url)
with pd.ExcelWriter(r'export.xlsx', engine="openpyxl") as writer:
#file will be written to /databricks/driver/ i.e., local file system
data.to_excel(writer)
dbutils.fs.ls("/databricks/driver/") indicates that the path you want to use to list the files is dbfs:/databricks/driver/ (absolute path) which does not exist.
/databricks/driver/ belongs to the local file system (DBFS is a part of this). The absolute path of /databricks/driver/ is file:/databricks/driver/. You can list the contents of this path by using either of the following:
import os
print(os.listdir("/databricks/driver/")
#OR
dbutils.fs.ls("file:/databricks/driver/")
So, use the file located in this path and move (or copy) it to your destination using shutil library as the following:
from shutil import move
move('/databricks/driver/export.xlsx','/dbfs/tmp/export.xlsx')
I just noticed that when I try to import metpy.plots on NCAR's Cheyenne supercomputer, it loads and works fine when using metpy 0.10.0 (with Cartopy 0.17.0), but I get an error with metpy 0.12.0 or 0.12.1 (with Cartopy 0.18.0b2). This is the error I get:
(NPL) jaredlee#cheyenne3:~> python3
Python 3.6.8 (default, Jun 27 2019, 20:02:05)
[GCC 8.3.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import metpy
>>> metpy.__version__
'0.12.1'
>>> import metpy.plots as mpplots
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/glade/work/jaredlee/python/my_npl_clone_20200417/lib/python3.6/site-packages/metpy/plots/__init__.py", line 27, in <module>
from .cartopy_utils import USCOUNTIES, USSTATES
File "/glade/work/jaredlee/python/my_npl_clone_20200417/lib/python3.6/site-packages/metpy/plots/cartopy_utils.py", line 43, in <module>
USCOUNTIES = MetPyMapFeature('us_counties', '20m', facecolor='None', edgecolor='black')
File "/glade/work/jaredlee/python/my_npl_clone_20200417/lib/python3.6/site-packages/metpy/plots/cartopy_utils.py", line 16, in __init__
super().__init__('', name, scale, **kwargs)
File "/glade/work/jaredlee/python/my_npl_clone_20200417/lib/python3.6/site-packages/cartopy/feature/__init__.py", line 264, in __init__
self._validate_scale()
File "/glade/work/jaredlee/python/my_npl_clone_20200417/lib/python3.6/site-packages/cartopy/feature/__init__.py", line 274, in _validate_scale
'Valid scales are "110m", "50m", and "10m".'
ValueError: 20m is not a valid Natural Earth scale. Valid scales are "110m", "50m", and "10m".
>>>
If I manually change cartopy_utils.py in my local copy of metpy so that the USCOUNTIES and USSTATES function calls to MetPyMapFeature use '10m' instead of '20m', then the error goes away. Is this '20m' a bug in cartopy_utils.py? Natural Earth's webpage advertises that it provides data at 1:10m, 1:50m, and 1:110m scales.
MetPy <=0.12.1 is incompatible with CartoPy 0.18. As pointed out by Daryl in his comment, this is an open issue that will hopefully be resolved soon.
I am running basic pyspark program as below in PySpark (1.6.0) but I am getting error. As per PySpark documentation https://spark.apache.org/docs/1.6.0/sql-programming-guide.html, the syntax seems to be correct but still not sure why it saying that 'SQLContext' object has no attribute 'textFile'
from pyspark import SparkContext,SparkConf
from pyspark.sql import SQLContext
if __name__ == '__main__':
conf = SparkConf().setAppName('TestingDF')
sc = SparkContext(conf=conf)
sqlc = SQLContext(sc)
lines = sqlc.textFile('/user/cloudera/practice4/question3/customers').map(lambda x: x.split(','))
I am getting below error
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'SQLContext' object has no attribute 'textFile'
'/user/cloudera/practice4/question3/customers' is basically sql table that I imported to HDFS from mysql via sqoop command
Python version is 2.6.6 (Basically I am testing all this on cloudera Quickstart VM 5.13)
My input is:
test=pd.read_csv("/gdrive/My Drive/data-kaggle/sample_submission.csv")
test.head()
It ran as expected.
But, for
test.to_csv('submitV1.csv', header=False)
The full error message that I got was:
OSError Traceback (most recent call last)
<ipython-input-5-fde243a009c0> in <module>()
9 from google.colab import files
10 print(test)'''
---> 11 test.to_csv('submitV1.csv', header=False)
12 files.download('/gdrive/My Drive/data-
kaggle/submission/submitV1.csv')
2 frames
/usr/local/lib/python3.6/dist-packages/pandas/core/generic.py in
to_csv(self, path_or_buf, sep, na_rep, float_format, columns,
header, index, index_label, mode, encoding, compression, quoting,
quotechar, line_terminator, chunksize, tupleize_cols, date_format,
doublequote, escapechar, decimal)
3018 doublequote=doublequote,
3019 escapechar=escapechar,
decimal=decimal)
-> 3020 formatter.save()
3021
3022 if path_or_buf is None:
/usr/local/lib/python3.6/dist-packages/pandas/io/formats/csvs.pyi
in save(self)
155 f, handles = _get_handle(self.path_or_buf,
self.mode,
156 encoding=self.encoding,
--> 157
compression=self.compression)
158 close = True
159
/usr/local/lib/python3.6/dist-packages/pandas/io/common.py in
_get_handle(path_or_buf, mode, encoding, compression, memory_map,
is_text)
422 elif encoding:
423 # Python 3 and encoding
--> 424 f = open(path_or_buf, mode,encoding=encoding,
newline="")
425 elif is_text:
426 # Python 3 and no explicit encoding
OSError: [Errno 95] Operation not supported: 'submitV1.csv'
Additional Information about the error:
Before running this command, if I run
df=pd.DataFrame()
df.to_csv("file.csv")
files.download("file.csv")
It is running properly, but the same code is producing the operation not supported error if I try to run it after trying to convert test data frame to a csv file.
I am also getting a message A Google Drive timeout has occurred (most recently at 13:02:43). More info. just before running the command.
You are currently in the directory in which you don't have write permissions.
Check your current directory with pwd. It might be gdrive of some directory inside it, that's why you are unable to save there.
Now change the current working directory to some other directory where you have permissions to write. cd ~ will work fine. It wil chage the directoy to /root.
Now you can use:
test.to_csv('submitV1.csv', header=False)
It will save 'submitV1.csv' to /root
I have a pyspark dataframe child with columns like:
lat1 lon1
80 70
65 75
I am trying to convert it into numpy matrix using IndexedRowMatrix as below:
from pyspark.mllib.linalg.distributed import IndexedRow, IndexedRowMatrix
mat = IndexedRowMatrix(child.select('lat','lon').rdd.map(lambda row: IndexedRow(row[0], Vectors.dense(row[1:]))))
But its throwing me error. I want to avoid converting to pandas dataframe to get the matrix.
error:
Py4JJavaError: An error occurred while calling z:org.apache.spark.api.python.PythonRDD.runJob.
: org.apache.spark.SparkException: Job aborted due to stage failure: Task 0 in stage 33.0 failed 4 times, most recent failure: Lost task 0.3 in stage 33.0 (TID 733, ebdp-avdc-d281p.sys.comcast.net, executor 16): org.apache.spark.api.python.PythonException: Traceback (most recent call last):
File "/data/02/yarn/nm/usercache/mbansa001c/appcache/application_1506130884691_56333/container_e48_1506130884691_56333_01_000017/pyspark.zip/pyspark/worker.py", line 174, in main
process()
You want to avoid pandas, but you try to convert to an RDD, which is severely suboptimal...
Anyway, assuming you can collect the selected columns of your child dataframe (a reasonable assumption, since you aim to put them in a Numpy array), it can be done with plain Numpy:
import numpy as np
np.array(child.select('lat1', 'lon1').collect())
# array([[80, 70],
# [65, 75]])