Skip to main content
  • Dask
  • Get Started
  • Community
    • Get Help
    • Powered By
  • Blog
  • Docs
Ctrl+K

Dask Blog

  • Motivation
  • Setup
  • Setup
  • Introduction
  • Introduction
    • Introduction
    • Introduction
    • Dask arrays work
    • Introduction
    • Evaluate dask graphs
    • Most Parallel Computation is Simple
    • Recent Parallel Work Focuses on Big Collections
    • Humans Repeat Stuff
    • Distributed Computing
    • Collections
    • GitHub Archive Data on S3
    • Play with Distributed Data
    • Setup
    • Identify a Problem
    • TL;DR.
    • What is grid search?
    • Introduction
    • Major Changes and Features
    • Biggest difference: Worker state and communication
    • Example: Kubernetes
    • Embedded Bokeh Servers in Dask Workers
    • Dask array without known chunk sizes
    • Rewriting Load Balancing
    • Load Balancing Cleanup
    • Summary
    • Summary
    • Summary
    • Stability enhancements and micro-release
    • Summary
    • Stability enhancements and micro-release
    • Summary
    • Summary
    • Dask-GLM and iterative algorithms
    • Summary
    • Summary
    • Arrays
    • Summary
    • Summary
    • Joblib
    • Arrays
    • NumPy ufuncs operate as Dask.array ufuncs
    • CSV is convenient, but slow
    • Summary
    • New dask-core and dask conda packages
    • Deploying Dask with MPI
    • TL;DR:
    • Masked Arrays
    • Summary
    • Summary
    • Cython
    • Breaking Changes
    • Community Communication
    • The Problem
    • This is a guest post
    • Deprecations
    • Minimal Complete Verifiable Examples
    • Tornado 5.0
    • Executive Summary
    • Context
    • History
    • Yarn deployment
    • Easy to Contribute
    • Dask on HPC Machines
    • Pickle is slow
    • Stateful processing with Actors
    • Start
    • Question
    • Notable Changes
    • 1: Update Dask Examples to use JupyterLab extension
    • Summary
    • Introduction
    • What 1.0 means to us
    • Combine Dask Array with CuPy
    • Executive Summary
    • Summary
    • Notable Changes
    • Summary
    • Executive Summary
    • Summary
    • Summary
    • Setup
    • Numba Stencils
    • Executive Summary
    • Reasons why we use Dask
    • Executive Summary
    • Executive Summary
    • Install
    • TL;DR
    • Notable Changes
    • 2019 Dask User Survey Results
    • Executive Summary
    • Power Architecture
    • First, why would you do this?
    • Problem
    • Groupby Aggregations with Dask
    • Summary
    • Bots dominate download counts
    • Who came?
    • Summary
    • Video
    • Summary
    • Manual setup
    • How to host a distributed Dask cluster
    • Consistency with the Scikit-Learn API
    • Why should open source projects run tutorials
    • History
    • Highlights
    • Summary
    • History
    • Executive Summary
    • The problem: fixed processing chunks and a high memory/CPU ratio {#problem}
    • Executive Summary
    • Executive Summary
    • Executive Summary
    • Motivation for change
    • Executive Summary
    • Why take the survey?
    • In the beginning
    • Motivation
    • Executive Summary
    • Executive Summary
    • Executive Summary
    • Overview
    • Contents
    • Progress Overview
    • Summary
    • Executive Summary
    • Summary
    • Introduction
    • Executive Summary
    • Summary
    • What is meta?
    • What is an operator?
    • Slow is smooth
    • Visualization at Lightning Speed
    • Dispatching for Array Creation
    • What is Flyte?
    • What is Shuffling?
    • What is from_map?
    • What does this mean for me?
    • Nightly testing
    • Introduction
    • Intro
    • What is GroupBy.map?
  • GitHub
  • Motivation
  • Setup
  • Setup
  • Introduction
  • Introduction
  • Introduction
  • Introduction
  • Dask arrays work
  • Introduction
  • Evaluate dask graphs
  • Most Parallel Computation is Simple
  • Recent Parallel Work Focuses on Big Collections
  • Humans Repeat Stuff
  • Distributed Computing
  • Collections
  • GitHub Archive Data on S3
  • Play with Distributed Data
  • Setup
  • Identify a Problem
  • TL;DR.
  • What is grid search?
  • Introduction
  • Major Changes and Features
  • Biggest difference: Worker state and communication
  • Example: Kubernetes
  • Embedded Bokeh Servers in Dask Workers
  • Dask array without known chunk sizes
  • Rewriting Load Balancing
  • Load Balancing Cleanup
  • Summary
  • Summary
  • Summary
  • Stability enhancements and micro-release
  • Summary
  • Stability enhancements and micro-release
  • Summary
  • Summary
  • Dask-GLM and iterative algorithms
  • Summary
  • Summary
  • Arrays
  • Summary
  • Summary
  • Joblib
  • Arrays
  • NumPy ufuncs operate as Dask.array ufuncs
  • CSV is convenient, but slow
  • Summary
  • New dask-core and dask conda packages
  • Deploying Dask with MPI
  • TL;DR:
  • Masked Arrays
  • Summary
  • Summary
  • Cython
  • Breaking Changes
  • Community Communication
  • The Problem
  • This is a guest post
  • Deprecations
  • Minimal Complete Verifiable Examples
  • Tornado 5.0
  • Executive Summary
  • Context
  • History
  • Yarn deployment
  • Easy to Contribute
  • Dask on HPC Machines
  • Pickle is slow
  • Stateful processing with Actors
  • Start
  • Question
  • Notable Changes
  • 1: Update Dask Examples to use JupyterLab extension
  • Summary
  • Introduction
  • What 1.0 means to us
  • Combine Dask Array with CuPy
  • Executive Summary
  • Summary
  • Notable Changes
  • Summary
  • Executive Summary
  • Summary
  • Summary
  • Setup
  • Numba Stencils
  • Executive Summary
  • Reasons why we use Dask
  • Executive Summary
  • Executive Summary
  • Install
  • TL;DR
  • Notable Changes
  • 2019 Dask User Survey Results
  • Executive Summary
  • Power Architecture
  • First, why would you do this?
  • Problem
  • Groupby Aggregations with Dask
  • Summary
  • Bots dominate download counts
  • Who came?
  • Summary
  • Video
  • Summary
  • Manual setup
  • How to host a distributed Dask cluster
  • Consistency with the Scikit-Learn API
  • Why should open source projects run tutorials
  • History
  • Highlights
  • Summary
  • History
  • Executive Summary
  • The problem: fixed processing chunks and a high memory/CPU ratio {#problem}
  • Executive Summary
  • Executive Summary
  • Executive Summary
  • Motivation for change
  • Executive Summary
  • Why take the survey?
  • In the beginning
  • Motivation
  • Executive Summary
  • Executive Summary
  • Executive Summary
  • Overview
  • Contents
  • Progress Overview
  • Summary
  • Executive Summary
  • Summary
  • Introduction
  • Executive Summary
  • Summary
  • What is meta?
  • What is an operator?
  • Slow is smooth
  • Visualization at Lightning Speed
  • Dispatching for Array Creation
  • What is Flyte?
  • What is Shuffling?
  • What is from_map?
  • What does this mean for me?
  • Nightly testing
  • Introduction
  • Intro
  • What is GroupBy.map?
  • GitHub

Tags

  • Australia
  • Community
  • CuPy
  • Dask
  • Dask Gateway
  • Dask Summit
  • Dask-GLM
  • Deployment
  • Distributed
  • Flyte
  • GPU
  • HPC
  • Helm
  • IO
  • Kubernetes
  • MPI
  • Organisations
  • Pandas
  • Programming
  • PyTorch
  • Python
  • RAPIDS
  • SciPy
  • Sparse
  • Talk
  • Tools
  • Tutorials
  • User Survey
  • array
  • clusters
  • config
  • cupy
  • dask
  • dask array
  • dask-image
  • dask-kubernetes
  • dask-ml
  • dataframe
  • deep learning
  • deployment
  • distributed
  • ecosystem
  • geoscience
  • image analysis
  • imaging
  • jobqueue
  • kubernetes
  • life science
  • machine-learning
  • memory
  • numba
  • p2p
  • pangeo
  • performance
  • profiling
  • pydata
  • python
  • query optimizer
  • ram
  • ray
  • release
  • scikit-image
  • scipy
  • shuffling
  • skan
  • skeleton analysis
  • xarray

Archives

  • 2024 (2)
  • 2023 (7)
  • 2022 (7)
  • 2021 (20)
  • 2020 (12)
  • 2019 (24)
  • 2018 (20)
  • 2017 (28)
  • 2016 (14)
  • 2015 (13)
  • 2014 (2)

Posts by Benjamin Zaitlen & James Bourbeau

DataFrame Groupby Aggregations

  • Oct 08, 2019
  • Benjamin Zaitlen & James Bourbeau
  • dask dataframe

Document headings start at H2, not H1 [myst.header]

Read more ...

By Dask Contributors

© Copyright 2014-2026, Dask Contributors.

Get Started

  • Documentation
  • Install
  • Examples

Community

  • Get Help
  • Powered By
  • Ecosystem

Blog

  • Dask Blog
  • Contribute

Brand

  • Brand Guidelines
Copyright © 2014-2026, Dask Contributors New-BSD Licensed.