Questions tagged [pyspark]
The Spark Python API (PySpark) exposes the apache-spark programming model to Python.
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questions
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22 views
cannot access hive from spark [closed]
I am trying to install a hadoop + spark + hive cluster.
I am using hadoop 3.1.2, spark 2.4.5 (scala 2.11 prebuilt with user-provided hadoop) and hive 2.3.3 (also tried 3.1.2 with the exact same ...
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1answer
19 views
Spark/Databricks: GPU does not appear to be utilized for ML regression (cross-validation, prediction) notebook
I have created and attached a notebook to a GPU-enabled Databricks cluster (6.4 ML (includes Apache Spark 2.4.5, GPU, Scala 2.11), EC2 type: p2.xlarge).
I have started running the notebook that ...
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1answer
18 views
Pyspark Dataframes to Pandas and ML Ops - Parallel Execution Hold?
If I convert a spark dataframe into a pandas dataframe and subsequently apply pandas operations and sklearn models to the dataset in databricks, will the operations from pandas and sklearn be ...
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2answers
79 views
Is there a cost associated with converting Koalas dataframe to Spark dataframe?
I know that pandas works "under the hood" with numpy arrays stored in dictionaries. In contrast, Koalas works with the underlying Spark framework. Does that mean that there is no extra cost associated ...
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1answer
52 views
PySpark: How do I specify dropna axis in PySpark transformation?
I would like to drop columns that contain all null values using dropna(). With Pandas you can do this with setting the keyword argument ...
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1answer
44 views
How to apply K-Medoids in PySpark?
the pyspark ml library does not provide any clustering methods for K-Medoids. So my question is, how can one apply K-Medoids in a pyspark context?
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15 views
Tool/Technology/Framework to process file with 1GB
I'm new to datascience, but I have the following problem:
1) Read a file of 1GB, which each line is a json object
2) There are two more files, much smaller, which I need to JOIN some data
In this ...
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1answer
46 views
How to split a CSV into a dataframe without newline
Currently I'm using pyspark to make my df from a csv. However when I take the data in, it puts each element on a new line. Is there any way to keep the elements separate, and keep them on the same ...
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65 views
Machine learning after Cosine Similarity for fuzzy name matching
I am following ING Bank's Large Scale Fuzzy Name Matching and I have implemented their awesome_cossim_topn to produce a dataframe of names and their associated similarities. I then added the other ...
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0answers
48 views
Feature importance using logistic regression in pyspark
I am using logistic regression in PySpark. I have after splitting train and test dataset
...
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0answers
19 views
Online learning/ Incremental modelling in pyspark
Can online learning of a model is possible in Pyspark? Does Mlib library in pyspark supports that. If so how it can be done
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1answer
30 views
Incremental modelling of kmeans in pyspark
I have a large dataset and trained the model with kmeans for the first time. I saved the model and pipeline used . Now again I started collecting data. After sufficient data is collected using old ...
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1answer
71 views
Calculating Rank Ordering Error Metric for implicit recommendation
I'm reading Collaborative Filtering for Implicit Feedback Datasets. On page 6 they detail their evaluation strategy, which they define as mean Expected Percentile Ranking with the following formula:
$...
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1answer
1k views
How to select multiple columns in a RDD with Spark (pySpark)?
Lets say I have a RDD that has comma delimited data. Each comma delimited value represents the amount of hours slept in the day of a week.
So for i.e. [8,7,6,7,8,8,5]
How can I manipulate the RDD so ...
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0answers
9 views
(Py)Spark infrastructure for use in Java/C# website
Lets say I have experience creating ML models in Python, and have decided on training my models on Spark using Pyspark. This will form part of an ML infrastructure for a website with a Java or C# ...
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47 views
Running LSTM model on a big data sample using pyspark
I was wondering how does one run an LSTM model on a big dataframe in pyspark. Ideally, one wants to run the model parallelly on different nodes of a spark cluster. But how does one do that?
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36 views
Unseing label in PySpark MultilayerPerceptronClassifier
I'm trying to perform classification with a MLP in PySpark:
...
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2answers
40 views
customer segmentation with unbalanced data
I am trying to do a customer segmentation on my transactional data and I am struggling a little bit on the best approach. Since it is an unsupervised model I can throw it to any algorithm and get some ...
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1answer
24 views
Which ML method for multiclass (non-binary) text classification should I choose (from SparkML)?
I am working on a quite big dataset that will be processed on the cluster, so this is why I am using PySpark for that purpose.
The presentable records of this dataset have a such structure:
...
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1answer
29 views
How to store subset of columns from a csv file?
I need to create a table in hive (or Impala) by reading from a csv file (named file.csv), ...
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0answers
46 views
Jupyter notebook pyspark error in %manage_spark
The environment is Jupyterhub on Centos using Pyspark kernel. When trying to run the below commands in JupyterLab I get errors. But the same commands work fine if I revert to regular Jupyter notebook ...
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0answers
32 views
Setting up Zeppelin to work with a Spark Cluster
I have made a spark cluster containing 2 workers and 1 master. I followed the following link to set up the spark clusters. After successfully setting up the spark clusters I wanted to connect it to ...
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1answer
54 views
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36 views
How to read binary video format in HDFS using pyspark?
We want to work on detection of pedestrians in a video using ML algorithm.But the video is in the HDFS file system.How can we read the binary video file format from HDFS using spark?
Please help me ...
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47 views
How to score AFT survival model in pyspark?
I am using AFTSurvivalRegression package in pyspark. I have a label which is time and censor which is 1 or 0 for those event that already happened or not as well as some features. I plugged them in ...
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21 views
how to run pyspark on Hadoop cluster, cache data, then read file using pandas on local machine via its URI?
I connect to a Hadoop cluster via vpn. I want to execute a script that makes sql call and saves the data to a file on the remote machine, then using its URI I want to read on my local running Jupiter ...
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1answer
32 views
Regarding join in pyspark
Given a rdd in pyspark, $A=[(0, 1), (1, 2), (1, 3), (3, 0)]$
I am trying to find self join of A such that the second element of previous pair is equal to first element of next pair i.e.
$...
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60 views
sorting pyspark dataframe
I'm sorting a pyspark DataFrame in databricks by df.sort(desc('x')). However, when I look at the DataFrame by display(df), I don't see the DataFrame being sorted in 'x'. What could be the reason?
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205 views
Python data cleaning for CSV using Pandas and PySpark and mapping to JSON in AWS ETL Glue Environment
I have recently started working on some ETL work and wanted some guidance in this area related to data cleaning from CSV to JSON mapping using AWS Glue, Python (pandas, pyspark).
Question
Need a ...
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1answer
899 views
PicklingError: Could not serialize object: TypeError: can't pickle fasttext_pybind.fasttext objects
I built a fasttext classification model in order to do sentiment analysis for facebook comments (using pyspark 2.4.1 on windows). When I use the prediction model function to predict the class of a ...
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0answers
212 views
Pyspark: Filter dataframe based on separate specific conditions
How can I select only certain entries that match my condition and from those entries, filter again using regex?
For instance, I have this dataframe (df)
...
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0answers
39 views
Where is $SPARK_HOME on an EC2 instance?
I am working on an EC2 instance with anaconda and pyspark pre-installed. My $SPARK_HOME variable is not set. Any ideas on how to locate my spark home?
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2answers
111 views
Record Linkage problem
I am building Matching Alogoritm using ML.Project is to match Internal customer data with external customer data.Features are names,address,city,state and zip.
We create pairs between data sets and ...
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6 views
PCAModel and PipelineModel, how to get explainedVariance
in pyspark PCAModel contains explainedVariance() method , but once you use Pipeline and specify PCA as a "stage", you will get a PipelineModel as an output and this one does not contain ...
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1answer
220 views
Pyspark Pipeline Custom Transformer
I'm having some trouble understanding the creation of custom transformers for Pyspark pipelines.
I am writing a custom transformer that will take the dataframe column Company and remove stray commas:
...
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0answers
18 views
Data sharing between Custom Tranformer and estimator in pyspark
Using Titanic Dataset for classification. Created custom Estimator and transformer for pipeline. some of logical operation need to be done in fit() method and data ...
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0answers
72 views
I got a overall mean average precision score of 0 for a recommendation engine
I just wanted to know if receiving an overall MAP score of 0 in a recommendation engine was possible, or a sign that my calculation or my logic for the engine was wrong.
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46 views
Code completion and suggestion EMR Notebook
I Created an EMR Cluster with Pyspark and connected to its notebook.
However i noticed there's no code completion neither method documentation.
Has anyone ever had the same issue? Didi you solve it?
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4
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2answers
513 views
Model ensemble with Spark or Scikit Learn
I am using Spark MLLib to make prediction and I would like to know if it is possible to create your custom Estimators.
Here is a reproducible of what I would like my model to do with the Spark api
<...
1
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1answer
385 views
Getting parameters of the best model with crossvalidation in with SparkMLLib
I am having trouble accessing the parameters of estimators of model in SparkMLlib. More precisely my problem is:
I have a logistic regression model for which I want to find the best regularization ...
2
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2answers
429 views
K-modes implementation in pyspark
I'm looking for an implementation of k-modes in pyspark. I found this and this as implementations.
First, I tried implementing k-modes using the first link and faced issues. So I went ahead and tried ...
2
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0answers
54 views
Obtain learning curve of Gradient Boosted Tree model in PySpark
Currently there seems to be no method in PySpark of checkpointing the performance of a model at each gradient update. Is there a way to get the performance of a model at each gradient update so that a ...
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1answer
106 views
Null predictions for ALS in Pyspark
I am trying to read from my dataset which has three coloumns. (User, Repository and Number of Stars)
In[10]
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1answer
3k views
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2answers
815 views
PySpark v Pandas Dataframe Memory Issue
Suppose I have a csv file with 20k rows, which I import into Pandas dataframe. I then run models like Random Forest or Logistic Regression from sklearn package and it runs fine. However, when I import ...
2
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0answers
255 views
What is the difference between PySpark's featuresCol, labelCol, predictionCol, and probabilityCol?
I am attempting to train a random forest classifier (pyspark.ml.classification.RandomForestClassifier) on a large dataset (~70gb). However, I am not sure what to ...
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1answer
433 views
Using keras tokenizer on Spark DataFrame. Column is not iterable [closed]
I am having trouble using the Tokenizer
The code is
...
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0answers
169 views
alternatives to pyspark to query a csv file locally (no distributed computation needed)
I am reading a csv file with pyspark to extract some information from it. I am running pyspark locally and I do not need distributed computation. On the contrary I need some plotting library such as ...
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0answers
15 views
Is there a built-in pyspark function for the paradigm union(filter, take)? [closed]
Essentially, filtering by key, taking a specific number (based on key) from the DataFrame, and unioning these results for a number of values.
For example,
...
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1answer
54 views
Best Data Science & Machine Learning Conferences 2019? [closed]
What are the best data science conferences you have attended? I am looking for a conference that will help me further develop my Data Science and Machine Learning competencies. Topics that are ...
