I'm using Jupyter NoteBook to run pySpark code to import CSV file to Cassandra v3.11.3. Getting below error.
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pySpark Code i have attached as picture:
[![pyspark_code][1]][1]
Any inputs...
Without the full trace it's hard to know exactly where this is failing. The method you pasted is just the p4yj wrapper method and we really would need to see the underlying Java Exception.
From what I can tell it looks like you are attempting to also use some options on the C* write that are unsupported. For example "MODE" - "DROPMALFORMED" is not a valid C* connector option. DataFrame Writer and Reader options are source specific so you are unfortunately unable to mix and match.
This makes me think that the data being written actually has a malformed date string or two and this code is dying when attempting to write the broken record. One way around this would be to attempt to do the date casting on CSV read which I believe does support DROPMALFORMED style parsing options.
Related
I am stuck in an issue while trying to read a csv file with multiline=true option in spark that has characters like Ř and Á. The csv is read in utf-8 format ; But when we try to read the data by using multiline=true we get characters that are not equivalent to the ones that we had read. We get something like ŘÃ�. So essentially a word read as ZŘÁKO gets transformed to ZŘÃ�KO.I went through several other questions asked on stack overflow around the same issue but none of solution actually works !
I tried the following encodings while read/write operations : ‘US-ASCII’
‘ISO-8859-1’,‘UTF-8’,‘UTF-16BE’,‘UTF-16LE’,‘UTF-16’,SJIS and couple more but none of them could give me the expected result. But multiline=false generates the correct output somehow.
I cannot read/write the file as text as the current framework policy of project is around an ingestion framework where we read the file only once and then everything is expected to be done in-memory and I must use multiline as true.
I would really appreciate any thoughts on this matter. Thank You !
sample data:
id|name
1|ZŘÁKO
df=spark.read.format('csv').option('header',true).
option('delimter','|').option('multiline',true).option('encoding','utf-8').load()
df.show()
ouptut :
1|Z�KO
#trying to force utf-8 encoding as below :
df.withColumn("name", sql.functions.encode("name", 'utf-8'))
gives me this :
1|[22 5A c3..]
I tried the above steps with all the supported encodings in spark
Short version:
I am trying to upload US LCI database to Brightway2 and I am failing miserably. Has anyone succeeded? If so, could you share it with me? :D
Long version:
I am following the notebook IO - Importing the US LCI database notebook and I am having a lot of problems. I am aware that, as the notebook indicates, it is a work in progress. Anyhow, I wanted to give it a try:
I tried uploading every ecospold version database found here, following the method from the notebook. The only one that gave me a similar results was version FY20.Q3.02. However, right off the bat I get the following differences/errors:
Same as the notebook, I get this error: Couldn't apply strategy link_technosphere_by_activity_hash: Object in source database can't be uniquely linked to target database. And two activities that are linked. When I follow the instructions of ignoring these datasets, it throws me that error over and over again.
Trying to move on with the tutorial, I get more errors and at the end I end up with all exchanges unlinked:
633 datasets
37513 exchanges
37505 unlinked exchanges
Finally, after running the code in line [15]:
import functools
f = functools.partial(link_iterable_by_fields,
other=Database(config.biosphere),
kind='biosphere'
)
sp.apply_strategy(f)
sp.statistics(f)
I end up with:
0 datasets
0 exchanges
0 unlinked exchanges
Which is hilarious and sad at the same time. Since I am new with Python and BW, my troubleshooting is clumpsy and probably erroneous (I promise I googled a lot and went through the code). And concluded I am failing and it is time to ask questions:
Has anybody succeeded uploading the US LCI database to Brightway2?
If so, how? Which file did you use?
Thank you!!!!
This is an excellent question. I have added text to the offending notebook to note that it is obsolete.
In general, I think trying to import the ecospold files is a fools errand, as though they are labeled ecospold2, they are actually ecospold1 (which is a totally different format):
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<ecoSpold xmlns="http://www.EcoInvent.org/EcoSpold01">
The most recent export also raises an error when I try the ecospold1 importer:
AttributeError: no such child: {http://www.EcoInvent.org/EcoSpold01}modellingAndValidation
This is a required attribute in ecospold1.
I think the best way forward would be to consume the JSON-LD directly. Note that it is important not to run bw2setup(), as you would also want to use their list of elementary flows and LCIA methods. Currently the experimental JSON-LD importer fails because the provided datasets need allocation, but don't provide a set of consistent allocation methods. When I use the git checkout of bw2io and do the following:
uslci = JSONLDImporter(
"/Users/cmutel/Downloads/National_Renewable_Energy_Laboratory-USLCI_Database/",
"US LCI",
preferred_allocation="CAUSAL_ALLOCATION"
)
uslci.apply_strategies()
I get the following error:
UnallocatableDataset: We currently only support exchange-specific CAUSAL_ALLOCATION
This is fixable, but someone would need to step through this and fix the allocation procedure, and I don't have the time to do that now.
I have set up a google cloud account
I want to perform my deep learning much more faster on a jupyter notebook, but
I cannot find a way to read my csv file
I downloaded it with wget from my github account and afterwards I tried
dataset = pd.read_csv('/home/user/.jupyter/SIEMENSTRAIN.csv')
but I get the following error
pandas.parser.CParserError: Error tokenizing data. C error: Expected 2 fields in line 3, saw 12
Why? When I read it on my laptop using my jupyter notebooks, everything runs well
Any suggestions?
I tried the recommended solutions for this error and I got the next warning
/home/user/anaconda3/lib/python3.5/site-packages/ipykernel/main.py:1: ParserWarning: Falling back to the 'python' engine because the 'c' engine does not support regex separators; you can avoid this warning by specifying engine='python'.
if name == 'main':
When I ran dataset.head() this is what appeared
Any help please?
There are a number of possibilities that could be causing the problem... I would first always make sure that Pandas (pd)'s version is updated and compatible.
The more likely cause is that the CSV itself is not right, so pd.read_csv() is not able to work correctly (thus a Parse Error). This may have something to do with the headers, though I'm not sure what your original CSV file looks like. It's worth playing around with read_csv, for example:
df = pandas.read_csv(fileName, sep='delimiter', header=None)
This tampers with 2 things - the delimiter, and if pd is reading a header from CSV or not.
I go through some pd.read_csv() stuff in my book about Stock Prediction (another cool Machine Learning problem) and Deep Learning, feel free to check it out.
Good Luck!
I tried what you proposed and this is what I got
So, any suggestions?
I suppose that the path is ok, but it just won't be read properly, or am I wrong?
Read CSV with linebreaks in pyspark
I want to read with pyspark a "legal" (it follows RFC4180) CSV that has breaklines (CRLF) in some of the rows. The next code sample shows how it does seem when opened it with Notepad++:
I try to read it with sqlCtx.read.load using format ='com.databricks.spark.csv. and the resulting dataset shows two rows instead of one in these specific cases. I am using Spark 2.1.0.2 version.
Is there any command or alternative way of reading the csv that allows me to read these two lines only as one?
You can use "csv" instead of Databricks CSV - the last one redirects now to default Spark reader. But, it's only a hint :)
In Spark 2.2 there was added new option - wholeFile. If you write this:
spark.read.option("wholeFile", "true").csv("file.csv")
it will read all file and handle multiline CSV.
There is no such option in Spark 2.1. You can read file using sparkContext.wholeTextFile or just use newer verison
wholeFile does not exist (anymore?) in the spark api documentation:
https://spark.apache.org/docs/2.2.0/api/python/pyspark.sql.html
This solution will work:
spark.read.option("multiLine", "true").csv("file.csv")
From the api documentation:
multiLine – parse records, which may span multiple lines. If None is set, it uses the default value, false
I used the following code to export an HBase table and save the output to HDFS:
hbase org.apache.hadoop.hbase.mapreduce.Export \
MyHbaseTable1 hdfs://nameservice1/user/ken/data/exportTable1
Output files are binary files. If I use pyspark to read the file folder:
test1 = sc.textFile('hdfs://nameservice1/user/ken/data/exportTable1')
test1.show(5)
It shows:
u'SEQ\x061org.apache.hadoop.hbase.io.ImmutableBytesWritable%org.apache.hadoop.hbase.client.Result\x00\x00\x00\x00\x00\x00\ufffd-\x10A\ufffd~lUE\u025bt\ufffd\ufffd\ufffd&\x00\x00\x04\ufffd\x00\x00\x00'
u'\x00\x00\x00\x067-2010\ufffd\t'
u'|'
u'\x067-2010\x12\x01r\x1a\x08clo-0101 \ufffd\ufffd\ufffd*(\x042\\6.67|10|10|10|7.33|6.67|6.67|6.67|6.67|6.67|6.67|5.83|3.17|0|0|0.67|0.67|0.67|0.67|0|0|0|0|0'
u'u'
I can tell that
'7-2010' in the 2nd line is the Rowkey,
'r' in the 4th line is the column family,
'clo-0101' in the 4th line is the column name,
'6.67|10|10|10|7.33|6.67|6.67|6.67|6.67|6.67|6.67|5.83|3.17|0|0|0.67|0.67|0.67|0.67|0|0|0|0|0' is the value.
I don't know where 3rd and 5th line came from. It seems like Hbase-export followed its own rule to generate the file, if I use my own way to decode it, data might got corrupted.
Question:
How can I convert this file back to a readable format? For example:
7-2010, r, clo-0101, 6.67|10|10|10|7.33|6.67|6.67|6.67|6.67|6.67|6.67|5.83|3.17|0|0|0.67|0.67|0.67|0.67|0|0|0|0|0
I have tried:
test1 = sc.sequenceFile('/user/youyang/data/hbaseSnapshot1/', keyClass=None, valueClass=None, keyConverter=None, valueConverter=None, minSplits=None, batchSize=0)
test1.show(5)
and
test1 = sc.sequenceFile('hdfs://nameservice1/user/ken/data/exportTable1'
, keyClass='org.apache.hadoop.hbase.mapreduce.TableInputFormat'
, valueClass='org.apache.hadoop.hbase.io.ImmutableBytesWritable'
, keyConverter='org.apache.spark.examples.pythonconverters.ImmutableBytesWritableToStringConverter'
, valueConverter='org.apache.spark.examples.pythonconverters.HBaseResultToStringCon verter'
, minSplits=None
, batchSize=100)
No luck, the code did not work, ERROR:
Caused by: java.io.IOException: Could not find a deserializer for the Value class: 'org.apache.hadoop.hbase.client.Result'. Please ensure that the configuration 'io.serializations' is properly configured, if you're using custom serialization.
Any suggestions? Thank you!
I had this problem recently myself. I solved it by going away from sc.sequenceFile, and instead using sc.newAPIHadoopFile (or just hadoopFile if you're on the old API). The Spark SequenceFile-reader appears to only handle keys/values that are Writable types (it's stated in the docs).
If you use newAPIHadoopFile it uses the Hadoop deserialization logic, and you can specify which Serialization types you need in the config-dictionary you give it:
hadoop_conf = {"io.serializations": "org.apache.hadoop.io.serializer.WritableSerialization,org.apache.hadoop.hbase.mapreduce.ResultSerialization"}
sc.newAPIHadoopFile(
<input_path>,
'org.apache.hadoop.mapreduce.lib.input.SequenceFileInputFormat',
keyClass='org.apache.hadoop.hbase.io.ImmutableBytesWritable',
valueClass='org.apache.hadoop.hbase.client.Result',
keyConverter='org.apache.spark.examples.pythonconverters.ImmutableBytesWritableToStringConverter',
valueConverter='org.apache.spark.examples.pythonconverters.HBaseResultToStringConverter',
conf=hadoop_conf)
Note that the value in hadoop_conf for "io.serializations" is a comma separated list which includes "org.apache.hadoop.hbase.mapreduce.ResultSerialization". That is the key configuration you need to be able to deserialize the Result. The WritableSerialization is also needed in order to be able to deserialize ImmutableBytesWritable.
You can also use sc.newAPIHadoopRDD, but then you also need to set a value for "mapreduce.input.fileinputformat.inputdir" in the config dictionary.