Big Data Science

🚀Speed up the quality and runtime of your Python code with Refurb
Every Data Scientist knows that Python is an interpreted language. Interpreted code is always slower than compiled to direct machine code because the interpreted instruction takes much longer to implement. Therefore, the way you write your Python code greatly affects the speed of its execution. Having a good code structure and respecting the language transformation will increase the speed of Python code. The Refurb library will help improve the quality of Python code. It can upgrade or change Python code with a single command. The library is inspired by clippy, Rust's built-in linter.
Just install it via pip package manager
pip install refurb
And use hints to improve the quality and speed of your Python code.
https://github.com/dosisod/refurb

🤔PyPy vs CPython: Under the Hood of Python
Every Python-developer knows about CPython, the most common implementation of a virtual machine that interprets written code. As alternative to CPython, there is PyPy built using the RPython language. Compared to CPython, PyPy is faster, implementing Python 2.7.18, 3.9.15, and 3.8.15. PyPy supports most of the commonly used Python library modules. The x86 version of PyPy runs on multiple instances such as Linux (32/64 bits), MacOS (64 bits), Windows (32 bits), OpenBSD, FreeBSD. Versions other than x86 are found on Linux, and ARM64 on MacOS.
However, PyPy doesn't scale up code in short-running processes that take less than a couple of seconds to load: the JIT compiler won't have enough time to "warm up". Also, PyPy does not give a speed gain if all the execution time falls on runtime libraries, i.e. in C functions, not in the actual execution of the Python code. Therefore, PyPy works best when executing executable programs, when bigger part of the time is spent executing Python code.
In terms of memory consumption, PyPy can also outperform CPython: Python programs with high RAM consumption (hundreds of MB or more) can end up taking up less space in PyPy than in CPython.
https://www.pypy.org/features.html

💥3 Useful Python Libraries for Data Science and More
Let’s introduce 3 libraries that can be useful in Data Science tasks:
• Fabric is a high-level Python library (2.7, 3.4+) for executing shell commands remotely over SSH to get useful Python objects. It is based on the Invoke API (execution of subprocess commands and command line functions) and Paramiko (an implementation of the SSH protocol). https://github.com/fabric/fabric
• TextDistance is a library for comparing the distance between two or more sequences using over 30 algorithms. Useful in NLP tasks to determine the distance and similarity between sequences. https://github.com/life4/textdistance
• Watchdog - Python API (3.6+) and shell utilities for monitoring file system events. Useful for monitoring directories specified as command line arguments, allows you to log generated events. https://github.com/gorakhargosh/watchdog

🌲TOP-5 DS-events in December 2022:
1. Nov 28-Dec 9 • NeurIPS 2022 https://nips.cc/
2. Dec 5-6 • 7th Global Conference on Data Science and Machine Learning, Dubai,UAE https://datascience.pulsusconference.com/
3. Dec 7 • Data Science Salon NYC | AI and ML in Finance & Technology • New York, NY, USA https://www.datascience.salon/newyork/
4.  Dec 12-16 • The 20th Australasian Data Mining Conference 2022 (AUSDM’22) • Sydney, Australia + Virtual https://ausdm22.ausdm.org/
5. Dec 17-18 • 3rd International Conference on Data Science and Cloud Computing (DSCC 2022), Dubai, UAE https://cse2022.org/dscc/index

On December 3, Sberbank is holding a One Day Offer for Data scientists, Data analysts and Data engineers. Pass all the selection stages in one day and get an offer from the largest bank in the country!

👨‍🎓We are looking for specialists in the field of AI, ML, RecSys, Watch V, NLP.

Our team create information products for decision-making based on data, analytics, machine learning and artificial intelligence.

👉 You will have to:
- Solve classification/regression/ uplift-modeling tasks;
- Support the output of models in the PROM;
- Analyze and monitor the quality of models;
- Calculate CLTV and Unit - economics;
- Interact with the validation and finance departments on assessing the quality of models/financial results issues.

Data on more than 1 billion transactions daily, 75PB of information, 100TB of memory and over 7,200 CPU cores in sandboxes will be available for work.

Become a part of the bank's AI community!

✍️ Send a request for participation

Yandex named the laureates of its annual scientific award

Scientists who are engaged in research in the field of computer science will receive one million rubles for the development of their projects. In 2022, six young scientists became laureates:

•Maxim Velikanov — is engaged in the theory of deep learning, studies infinitely wide neural networks and statistical physics;

•Petr Mokrov — studies Wasserstein gradient flows, nonlinear filtering and Bayesian logistic regression;

•Maxim Kodryan — is engaged in deep learning, as well as optimization and generalization neural network models;

•Ruslan Rakhimov — works with neural visualization, CV and deep learning;

•Sergey Samsonov — studies Monte Carlo algorithms with Markov chains, stochastic approximation and other topics;

•Taras Hahulin — works in the field of computer vision.

It's cool that scientific supervisors are singled out also separately. This year, two people received grants — Dmitry Vetrov, Head of the HSE Center for Deep Learning and Bayesian Methods, and Alexey Naumov, Associate Professor at the HSE Faculty of Computer Science, Head of the International Laboratory of Stochastic Algorithms and Analysis Multidimensional Data.

More information about the awards and laureates of 2022 can be found on the website

👍🏻Need beautiful graphs in Jupyter Notebook? It’s easy with PivotTable.js!
PivotTable.js is a Javascript implementation of source code pivot tables with drag and drop functionality. The project is distributed under the MIT license and compiled through the pip package manager:
pip install pivot tables
The library allows you to conveniently and quickly visualize the statistics of a data set by simply drag and drop the necessary data.
https://pypi.org/project/pivottablejs/

🔥Data validation in a Python script with the pydantic library
This lightweight library allows you to validate data and manage settings using Python annotations by applying type hints at runtime. The library shows errors if the data is invalid. It is enough to determine what the data should be in pure, canonical Python and check it with pydantic.
To be fair, pydantic is primarily a parsing library, not a validator. The library benefits from types and limits of the output model rather than the input. However, while model validation is not core pydantic, it can be used for this.
The main methods for defining objects in pydantic models are derived classes from the BaseModel base class. You can set up models as data types in strongly typed sizes. Untrusted data can be passed into models, and after parsing and checking pydantic parameters, that the fields of the resulting model instance will match the field types of the files in the models.
The library plays well with any IDE and is very fast: part of a large library is compiled with Cython. Pydantic performs complex data structure validation using recursive models, and allows you to define the characteristics of data types through the use of a decorator with parsing and validating input data.
It is noteworthy that this project with likely source code uses many companies and products, including FastAPI, Jupyter, Microsoft, AWS, Uber, etc. You can try it right now by importing it into your Python script, first find it yourself through the pip project manager, and then its base class is BaseModel:
pip install pydantic
from pydantic import BaseModel
https://pydantic-docs.helpmanual.io/

🤷‍♀️Not all missing data is equal
Missing data is a problem that often comes up in Data Science and Machine Learning. There are many reasons why data may be missing, depending on the type of data and collection methods. But not all missing data is the same, they can be broken down into the following categories:
• Missing due to the impossibility of their collection or the high cost of this procedure
• Structurally missing data that cannot be obtained due to the characteristics of the research objects;
• Missing due to random failure;
• Missing due to non-obvious or unknown reasons.
Depending on the reason for the lack of data in the dataset, you can smooth or even eliminate it. For example, structurally missing data suggests a change in the structure of questions about the object of study in order to get answers to them. Instead of collecting rare or expensive data, you can choose proxy metrics that allow you to make a decision. Constantly recurring failures need to be addressed, as well as more knowledge about the reasons for the lack of expected data.
https://medium.com/@nahmed3536/types-of-missing-data-e718e6ac2a55

🚀How to scale up Pandas with the Pandarallel library
Every Data Scientist knows that the Pandas Python library is quite slow and doesn't allocate large amounts of data. However, every Data Scientist uses it. 🤷‍♀️ To make Pandas faster, you can include Pandarallel in your project, a simple and convenient tool for parallelizing Pandas operations on all available processors.
Pandas only uses a single CPU profit, while Pandarallel allows you to profit from a multi-core computer. Pandarallel also offers progress bars for programs available on the laptop and terminal to get a rough idea of ​​the remaining results of the calculations that are needed to collect data.
The library can be used on any computer running Linux and macOS, and on Windows there are small quirks: due to the multiprocessor system, the function that is offered in Pandarallel must be standalone and must not be excluded from external sources.
https://nalepae.github.io/pandarallel/

👀TOP 5 Open Source Data lineage Tools
Data lineage allows a company to comply with regulatory requirements, better understand and trust its data, and save time on manually analyzing the effects of data changes. To monitor data, there are many tools on the market today, open source and proprietary. Of the source code tools, the most important are:
• Tokern allows users to get column-level data passing data from databases and data stores hosted by Google BigQuery, AWS Redshift, and Snowflake. Tokern can be integrated with other bugs as well. it works well with a large number of data directories with large source code and ETL frameworks. Tokern also provides users with the ability to generate data from external sources or its frequency ETL, making an overview for high end BI and ETL tools. Tokern uses PostgreSQL as its local storage, and NetworkX for quick analysis of network graphs. These available users can be manipulated, visualized, and analyzed in column-level library origin data. Additionally, users can also interact with walkthrough data using the Tokern SDK or API. Tokern also discovered PII (personal information) and PHI (personal health information) using PIICatcher, combining regular expressions with NLP libraries Spacy and Stanford NER.
• Egeria - a metadata standard with original source code, enabling seamless integration of data processing tools for a robust and unified representation of metadata. Egeria allows you to build better solutions for data production, data quality checks, PII identification, and more. in addition to cataloging and metadata retrieval. Egeria Law on the OpenLineage data collection and storage standard. This allows users to gain a more complete view of the data by providing horizontal and vertical assignment and tracing. To get information about the origin of the data, Egeria listens to the Kafka events sent by the original messages.
• Pachyderm is a data collection tool that empowers developers to create machine learning pipelines regardless of language and framework, instead of focusing on cloud storage. It uses a version control system like LakeFS or Git saves and saves changes like commits keeping a complete and unaltered audit trail. Pachyderm also has a full audit trail and uses a central repository based on object storage in a custom Pachyderm File System to track data generation and version control. Pachyderm collects user data sources, uses global origin event and data object identifiers. Pachyderm allows you to create an immutable data production graph as a DAG in the user interface, which is especially useful when working with ML pipelines. Thick Skin integrates well with many databases, repositories and data lakes. Therefore, many companies use it for MLOps operations, ETL unstructured data, and NLP workflows.
• OpenLineage is a Linux Foundation project based on the highest ETL platforms, data orchestration mechanisms, metadata catalogs, data quality control mechanisms, and data inheritance tools. OpenLineage uses JSONSchema as the API definition and supports multiple languages and platforms. The previously mentioned Egeria has a core metadata layer built on top of OpenLineage. WeWork's Marquez also underpins the OpenLineage architecture, a preferred UI and metadata repository, as well as an API for collecting metadata, validating via GraphQL, and a REST API.
• TrueDat is a comprehensive data management solution that allows you to efficiently classify, search and evaluate data, as well as visualize the entire data lifecycle. The tool was created in 2017 by BlueTab, which is part of IBM, and is still actively developed.
https://blog.devgenius.io/5-best-open-source-data-lineage-tools-in-2022-f8ef39a7d5f6

🐍Python instead of Cypher in Neo4j with Py2neo
Manipulations with data in the Neo4j graph database are performed using the SQL-like query language Cypher. It is graph-optimized, identifying and exploiting data relationships, exploring relationships in all directions to discover previously unseen relationships and clusters. However, Python gives you a lot of flexibility in working with data. Therefore, many Data Scientists prefer it for various programs, including automating the process of creating nodes and links.
Use the Py2neo library, a Python-package to work with Neo4j. It can be installed using the pip package manager through the well-known pip install py2neo command on the command line. Next, you can open your favorite Python editor and run the graph in Neo4j.
Py2neo includes a set of tools for working with Neo4j from Python applications and from the command line. The library supports both Bolt and HTTP and provides a high-level API, OGM, administration tools, an interactive console, a Cypher lexical encoder for Pygments, and many other features that come in handy for graph analysis. Starting with version 2021.1, Py2neo contains full routing support provided by the Neo4j cluster, which can be enabled using the neo4j://... URI or by passing the routing=True parameter to the Graph class constructor.
https://py2neo.org/2021.1/

🌞Easy prediction with Lazy Predict
Lazy Predict is a Python-library for comparing performance of different machine learning models in a dataset. In fact, this is a wrapper that allows you to quickly fit all ML models to a dataset and compare their performance in just a couple of lines of code. Lazy Predict works great with regression and classification of machine learning model comparison results by the most important metrics: R-Squared, RMSE, Accuracy (Precision), F1 Score and Training Time.
The library is open source and highly compatible with sklearn, numpy, and other Python libraries that are used in Data Science.
https://lazypredict.readthedocs.io/en/stable/readme.html

🚀Python 3.11.0: Major New Features for the Developer
On October 24, 2022, a new version of Python 3.11.0 was released. It provides the following new features and bug fixes:
• fixed multiplication of a list by an integer (list *= int), which resulted in an integer overflow when the new allocated length is close to the maximum size;
• Changed forkserver start method code - on Linux the multiprocessing module now uses unix domain sockets again, using the file system to operate on the forkserver process instead of the Linux abstract socket namespace. Abstract sockets do not have permissions and can be used on the system in the same network destination (particularly the entire system) to inject code into the forkserver multiprocessor process. This is a significant privilege escalation vulnerability and has been fixed in the new version of Python.
• Fixed an issue where frame objects could also be contained by the same interpreter frame, resulting in memory corruption and severe interpreter crashes;
• Fixed possible propagation of data or data sets when accessing the f_back element of a newly created generator or program frames;
• Fixed an implementation crash when calling PyEval_GetFrame() when the topmost Python frame is in a partially implemented state.
• command line parsing fixed: reject -X int_max_str_digits with no value is invalid when environment setting PYTHONINTMAXSTRDIGITS is set to a valid value;
• fixed undefined behavior in _testcapimodule.c;
• updated pip and setuptools archives to version 22.3 and 65.5.0 respectively;
• the asyncio.Task.cancel("message") method, previously declared discovered, now works again and is not found discovered;
• semaphores work faster, which is important for multitasking programs;
• fixed flag to use CONFORM bounds, allowing flags to be combined with unexplored values;
• on Windows, when typing Python tests behind the -jN option for a temporary stdout file, ANSI encoding is now used instead of UTF-8;
• fixed a bug due to which multiprocessing from the natural environment spawned child processes in Windows when it was not needed;
• fixed py.exe startup scheme with -V:<company>/ parameter when default settings were set in environment settings or configuration file;
• The macOS 13 SDK includes support for the mkfifoat and mknodat system calls. Previously, using the dir_fd option with os.mkfifo() or os.mknod() resulted in a segfault if cpython was built with the macOS 13 SDK but worked on an earlier version of macOS.

https://www.python.org/downloads/release/python-3110/
https://docs.python.org/release/3.11.0/whatsnew/changelog.html#python-3-11-0-final

🌨🍂Cool DS-events in November 2022 all over the world
Nov 1 • StreamSets Roadshow: SF Bay Area • San Mateo, CA, USA https://streamsets.com/roadshow/san-francisco/
Nov 1-3 • ODSC West 2022 • San Francisco, CA, USA https://odsc.com/california
Nov 2 • Modern Data Stack Roadshow • Denver, CO, USA https://www.moderndatastackroadshow.com/
Nov 2 • AiX Summit 2022 • San Francisco, CA, USA + Virtual https://odsc.com/california/aix-west/
Nov 2-3 • The AI Summit Austin • Austin, TX, USA https://austin.appliedintelligence.live/welcome
Nov 3 • StreamSets Roadshow: New York • New York, NY, USA https://streamsets.com/roadshow/new-york/
Nov 8 • The Data Science Symposium 2022, Presented by the UC Center for Business Analytics • Cincinnati, OH, USA https://web.cvent.com/event/36b0c2f9-5cfa-4f4c-875d-66c7f1ee2ed5/summary
Nov 8 • iMerit ML DataOps Summit 2022 • Virtual https://techcrunch.com/events/imerit-dataops-summit-2022/
Nov 9-10 • RE•WORK MLOps Summit • London, UK • https://london-ml-ops.re-work.co/
Nov 9-10 • Deep Learning Summit • Toronto, ON, Canada https://toronto-dl.re-work.co/
Nov 10 • Unleashing Hybrid and Multi-Cloud Data Science at Scale • Virtual https://www.dominodatalab.com/resources/unleashing-hybrid-multi-cloud-mlops
Nov 14-16 • Marketing Analytics & Data Science (MADS) Conference • San Antonio, TX, USA • https://informaconnect.com/marketing-analytics-data-science/
Nov 15-16 • Snowflake Build ‘22 • Virtual https://www.snowflake.com/build/
Nov 16-17 • 3rd Edition of Future Data Centres and Cloud Infrastructures • Dubai, UAE https://www.futuredatacentre.com/
Nov 16-17 • Smart Data Summit Plus 2022 • Dubai, UAE https://www.bigdata-me.com/
Nov 17-18 • Data Science Summit 2022 • Warsaw, Poland + Virtual https://dssconf.pl/
Nov 22 • trade/off: The Decision Intelligence Summit • Berlin, Germany https://www.tradeoff.ai/
Nov 22-23 • Nordic Data Science and Machine Learning Summit • Stockholm, Sweden + Virtual https://ndsmlsummit.com/

💥3 advantages and a couple of limitations of PySpark over Pandas
Although the Python-library Pandas is very popular among junior Data Scientists, it is not bound to work with really big data up to 10-12 GB. Although there are tools that can parallelize the work of Pandas, such as Dask, Swift, Ray, etc., this only speeds up the library, but does not address the root causes of the problems, because. Pandas always loads the dateframe into memory.
Therefore, dealing with large amounts of data requires something faster, such as PySpark - the Python API in Apache Spark, a distributed computing framework. Being distributed in its nature, Spark also uses lazy (deferred) evaluations, performing data operations not at the time of their declaration, but at an important call. This invariably sets many memory limits. Unlike PySpark, Pandas sticks to the Eager Execution by executing the reach task as early as possible, while PySpark follows the Lazy Execution, when the task is not elevated until after the action has been completed. PySpark is great for developing scalable applications and guarantees fault tolerance.
However, due to the networking of distributed computing, PySpark estimates a higher speed compared to local Pandas, which is indicative of the throughput of the application. In addition, PySpark remains demanding because all MapReduce tasks depend on RAM, without writing preliminary results to memory disk, unlike classical calculations in Hadoop. Finally, there are not so many specific algorithms for Data Science in PySpark.

Make it easy: Debugging Python Code with the IceCream Library
IceCream is a Python library that makes debugging easy and readable with minimal code. It includes printing expressions, variable names, function names, line numbers, file names, and much more that is useful to the developer when finding errors and fixing them. Instead of using print() or log() to debug code, the IceCream library has similar functions. In particular, ic() is similar to print(), but it prints the names of expressions, variables, and their values, and is 60% faster. The IceCream library more fully displays the examined data structures, has a rich output syntax, and can also include program context: file name, line number, and parent function.
IceCream's open source code is available on Github. The library supports Python 2, Python 3, PyPy2 and PyPy3, and can also be used in other programming languages: Dart, Rust, Node.js, C++, PHP, Go, Ruby, Java, R, Lua, Clojure(Script) and Bash .
Usage examples: https://towardsdatascience.com/introducing-icecream-never-use-print-to-debug-your-python-code-again-d8f2e5719f8a

🤔UDF in SQL: pros and cons
Data scientists and data analysts often write SQL queries that take a very long time. User Defined Functions (UDFs) can improve the speed of writing SQL queries. A UDF is at a basic level similar to a typical SQL function, but is used by the user. Technically, a UDF is a function that takes a set of typed parameters, applies change logic, and then returns a typed value. UDFs have a wide range of uses, including optimizing repetitive code and centralizing business logic to help you write SQL queries more efficiently. The use of UDF can be noted, but it has its repetitions. The main advantages of UDF:
• allows you to replace parts of complex or repetitive SQL code with one-line strings that make the code more readable. For example, a complex CASE statement spans many lines. With a UDF, it can be reduced to a single line.
• Encourages the use of process calculations, use them in parentheses to reuse them in new queries.
Thus, UDF speeds up code development, but it also has some disadvantages:
• Too many obscure UDFs can make code less readable, especially if they themselves expose obscurities like "func1" - it's not clear that the function does a division and the reader has to look up its definition, which takes more time than just reading it in the code .
• It will be necessary to keep a record of all emergency functions that arise, which is difficult when there are a large number of them. To do this, it is recommended to save the dictionary with the created UDFs and share it with the team. You can also create more generic functions to avoid rework.
https://towardsdatascience.com/save-time-writing-sql-with-udfs-24b002bf0192