Questions tagged [pyspark]
The Spark Python API (PySpark) exposes the apache-spark programming model to Python.
80
questions
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1answer
17 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 ...
3
votes
0answers
36 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)
...
1
vote
0answers
11 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?
1
vote
2answers
28 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 ...
0
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0answers
3 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 ...
2
votes
0answers
16 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:
...
0
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0answers
11 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 ...
0
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0answers
14 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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0answers
14 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
votes
1answer
143 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
<...
0
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0answers
14 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 ...
0
votes
1answer
108 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
votes
0answers
20 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 ...
0
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1answer
35 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]
...
0
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0answers
30 views
Can we use gunicorn to deploy pyspark models?
I have created a pyspark model and want to deploy it as a real time application. I am using Flask to handle requests and gunicorn to handle multiple requests by increasing workers and threads. To run ...
2
votes
0answers
287 views
1
vote
2answers
150 views
PySpark v Pandas Dataframe Memory Issue
Suppose I have a csv file with 20k rows, when I import in Pandas dataframe format and run the ML algos like Random Forest or Logistic Regression from sklearn package it just runs fine.
But same thing ...
0
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0answers
70 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 ...
0
votes
1answer
205 views
Using keras tokenizer on Spark DataFrame. Column is not iterable [closed]
I am having trouble using the Tokenizer
The code is
...
1
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0answers
152 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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vote
0answers
12 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,
...
1
vote
1answer
46 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 ...
0
votes
2answers
181 views
Why is there a difference of “ML” vs “MLLIB” in Apache Spark's documentation?
I am trying to figure out which pyspark library to use with Word2Vec and I'm presented with two options according to the pyspark documentation.
https://spark.apache.org/docs/2.2.0/mllib-feature-...
2
votes
1answer
302 views
cosine similarity between items (purchase data) and normalisation
I'm using IndexedRowMatrix which represents the products's user purchase behaviours and in order to build product recommendations, I use cosine similarity to calculate similarities between products. ...
0
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1answer
472 views
Accumulators in Spark (PySpark) without global variables?
BACKGROUND
Consider the following textbook example which uses accumulators to add vectors.
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1answer
1k views
PySpark: java.io.EOFException
System:
1 name node, 4 cores, 16 GB RAM
1 master node, 4 cores, 16 GB RAM
6 data nodes, 4 cores, 16 GB RAM each
6 worker nodes, 4 cores, 16 GB RAM each
around 5 Terabytes of storage space
The data ...
0
votes
2answers
2k views
Reliable way to verify Pyspark data frame column type
If I read data from a CSV, all the columns will be of "String" type by default. Generally, I inspect the data using the following functions which gives an overview of the data and its types
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1answer
3k views
Replacing null with average in pyspark
I have a problem during upsampling operation in PySpark. My dataframe is:
...
1
vote
1answer
3k views
Plotting in PySpark?
I have been searching for methods to plot in PySpark.
I couldn't find any resource on plotting data residing in DataFrame in PySpark. The only methods which are listed are:
through method ...
0
votes
2answers
75 views
Apache Spark Understanding
I have read a lot about Apache Spark. About RDD, DataFrames etc etc. But I haven't come across a simple explanation as to why and where should we be using Apache Spark? If my primary goal is machine/...
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vote
0answers
423 views
Frequent itemset vs. frequent sequence mining algorithms on variables with an inherent order
I've been using Pyspark's PrefixSpan algorithm to mine sequences of variables with an inherent order (bus stops). I know that PrefixSpan takes into consideration the order of the items it is fed, ...
4
votes
2answers
316 views
k-means|| in PySpark
I'm trying to apply k-means$\|$ clustering in PySpark.
According to this paper, there is an oversampling factor, $l$, that would affect the model's cost.
I couldn't find any parameter regarding ...
1
vote
0answers
6k views
Adding multiple columns to spark dataframe
I would like to add several columns to a spark (actually pyspark) dataframe , these columns all being functions of several input columns in the df. There seems to be no 'add_columns' in spark, and ...
1
vote
0answers
122 views
Running H2O in databricks
I'm trying to run H2O in databricks. However, when I do the following:
hc = pysparkling.H2OContext.getOrCreate(spark)
I get the following error:
java.lang.AbstractMethodError
Does anyone know what ...
0
votes
2answers
383 views
Exponential runtime on distance matrix
I have an exploratory script running a Databricks notebook that performs a simple arithmetic function (Pythagorean theorem) on all possible pairwise combinations of a list of pairs of floats (akin to ...
3
votes
1answer
3k views
2
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1answer
40 views
PySpark Filter shows only 1 row
I have a 12 GB .csv file and I am trying to filter rows based on some value in a column under "AppName"
Doing this in Pyspark:
...
4
votes
2answers
1k views
What are the alternatives to Python + Spark (pyspark)?
I like Python, and I like Spark, but they don't fit very well together. In particular,
it is very hard to use python functions in spark (have to create JVM binding for function in python)
it is ...
1
vote
1answer
346 views
Use of Random Forest algorithm in PySpark for imputation
I am wondering how to use Random Forest algorithm for imputing missing values in a dataset. It is supposed to work well with missing values but I am not sure how those missing values are dealt with ...
2
votes
1answer
2k views
Run python script using spark-submit on windows 7
I'm trying to submit a python script using spark-submit on windows 7. I'm using spark 2.3.0 built for hadoop 2.7 . The python script is supposed to read data from a csv file and plot graphs. is it ...
1
vote
0answers
19 views
Recommender system: Give a feature more significance than another
I am trying to build a recommender system that predicts hotel prices based on a great number of features. I have a column representing the hotel rating out of 5 and another column indicating the ...
6
votes
1answer
7k views
PySpark dataframe repartition
What happens when we do repartition on a PySpark dataframe based on the column. For example
dataframe.repartition('id')
Does this moves the data with the similar ...
0
votes
2answers
98 views
KMeans for crime patterns
I'm trying to find the patterns in the crime records I have in a database.
I thought clustering would be a way to do it.
This is my (cooked up) dataset:
...
0
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2answers
1k views
Filling missing values with pyspark using a probability distribution
I want to fill missing values in my dataframe.
...
3
votes
2answers
14k views
Is there any way to read Xlsx file in pyspark?Also want to read strings of column from each columnName
pd is a panda module is one way of reading excel but its not available in my cluster. I want to read excel without pd module. Code1 and Code2 are two implementations i want in pyspark.
Code 1: ...
0
votes
1answer
84 views
Install Spark and Hadoop in the same machine [closed]
I'm trying to install Spark Apache and Hadoop in the same machine. Spark will be used to process data, and HDFS from Hadoop will be used to store data. I first started by installing spark and it ...
4
votes
1answer
1k views
Spark development on local machine with PyCharm
I am wondering what is the best practice other devs are using for their python spark jobs.
I am building a dev environment in which I am looking to write code in PyCharm with SparkContext pointing to ...
1
vote
0answers
146 views
Creating a user-based recommendation engine?
I have a data set of some questions and answers that users have completed by choices. I'm trying to build a recommendation engine to find similar users based on their answers on top of this.
So for ...
1
vote
0answers
484 views
How to do Feature Extraction using Apache Spark
I am a newbie to Machine Learning and I have to do feature extraction for a banking application to detect / predict fraudulent transactions.
I have come across few articles on Feature Extraction ...
-1
votes
1answer
1k views
Words from LDA output pyspark machine learning
I built a pipeline for an LDA model using pyspark's machine learning.
Here is my code:
...
