Rdatatable / data.table

# data.table 
`data.table` provides a high-performance version of base R's `data.frame` with syntax and feature enhancements for ease of use, convenience and programming speed.
[//]: # (numfocus-fiscal-sponsor-attribution)
The `data.table` project uses a custom governance agreement 
and is fiscally sponsored by NumFOCUS. Consider making 
a tax-deductible donation to help the project 
pay for developer time, professional services, travel, workshops, and a variety of other needs.
## Why `data.table`?
* concise syntax: fast to type, fast to read
* fast speed
* memory efficient
* careful API lifecycle management
* community
* feature rich
## Features
* fast and friendly delimited **file reader**: **`?fread`**, see also convenience features for _small_ data
* fast and feature rich delimited **file writer**: **`?fwrite`**
* low-level **parallelism**: many common operations are internally parallelized to use multiple CPU threads
* fast and scalable aggregations; e.g. 100GB in RAM (see benchmarks on up to **two billion rows**)
* fast and feature rich joins: **ordered joins** (e.g. rolling forwards, backwards, nearest and limited staleness), **overlapping range joins** (similar to `IRanges::findOverlaps`), **non-equi joins** (i.e. joins using operators `>, >=, 1.0, mean(Petal.Length), by = Species]
# Species V1
#1: versicolor 4.362791
#2: virginica 5.552000
```
### Getting started
* Introduction to data.table vignette
* Getting started wiki page
* Examples produced by `example(data.table)`
### Cheatsheets
## Community
`data.table` is widely used by the R community. It is being directly used by hundreds of CRAN and Bioconductor packages, and indirectly by thousands. It is one of the top most starred R packages on GitHub, and was highly rated by the Depsy project. If you need help, the `data.table` community is active on StackOverflow.
A list of packages that significantly support, extend, or make use of `data.table` can be found in the Seal of Approval document.
### Stay up-to-date
- click the **Watch** button at the top and right of GitHub project page
- read NEWS file
- follow #rdatatable and the r_data_table account on X/Twitter
- follow #rdatatable and the r_data_table account on fosstodon
- follow the data.table community page on LinkedIn
- watch recent Presentations
- read recent Articles
- read posts on The Raft
### Contributing
Guidelines for filing issues / pull requests: Contribution Guidelines.