10 releases

0.1.0 Apr 28, 2019
0.0.16-a Dec 10, 2018
0.0.15 Sep 17, 2018
0.0.13 Aug 26, 2018

#147 in Database implementations

Custom license and GPL-3.0+

85KB
1.5K SLoC

black-jack

BlackJack is under development and PRs / issues are definitely welcome!

Build Status Coverage Status Dependabot Status License License

Rust API Documentation


BlackJack strives to be a full featured crate for general data processing.

Long term goal is to create a lightweight Pandas equivalent by and for the Rust community, but with slight differences in focus...

The project strives for a few key principles. When any implementation decisions are to be made, they are made with these principles in mind, and in this order:

  1. Memory efficiency
    • Minimize memory use at every opportunity.
  2. Usability
    • Strive for ergonomics; often done by modeling the Pandas API where possible.
  3. Speedy
    • It comes naturally most times with Rust. :)

Eventually we'll have a Python wrapper: Lumber-Jack associated with this crate, but that time will come.

Example use:


// We have a dataframe, of course...
let mut df = DataFrame::new();

// Make some series, of different types
let series_i32: Series<i32> = Series::arange(0, 5);
let mut series_f64: Series<f64> = Series::from_vec(vec![1.0, 2.0, 3.0, 4.0, 5.0]);

// You can set a series name!
series_f64.set_name("my-series");

// Or not... 
assert_eq!(series_i32.name(), None);

// And add them to the dataframe
df.add_column(series_f64).unwrap();
df.add_column(series_i32).unwrap();

// And then get a reference to a Series
let series_f64_ref: &Series<f64> = df.get_column("my-series").unwrap();

Read a CSV file:

Also supports reading .gz files


// Define the path to file
let path: &str = concat!(env!("CARGO_MANIFEST_DIR"), "/tests/data/medium_csv.csv");

// Use the `Reader` to read the dataframe
let df = Reader::new(&path).read().expect("Failed to read file");

// Get a refrence to a specific column and assert the sum of that series
let series2: &Series<i32> = df.get_column("col2").unwrap();

assert_eq!(series2.sum(), 3000);

Query/filter a dataframe

let mut s1 = Series::from(0..5);
s1.set_name("col1");

let mut s2 = Series::from(10..15);
s2.set_name("col2");

let mut s3 = Series::from_vec(vec![
    "foo".to_string(),
    "bar".to_string(),
    "foo".to_string(),
    "bar".to_string(),
    "foo".to_string(),
]);
s3.set_name("col3");

let mut df = DataFrame::new();
assert!(df.add_column(s1).is_ok());
assert!(df.add_column(s2).is_ok());
assert!(df.add_column(s3).is_ok());

// Before filtering, we're len 5 and first element of 'col1' is 0
assert_eq!(df.len(), 5);

df.filter_by_row(|row| row["col1"] == Datum::I32(&0));

// After filtering, we're len 4 and first element of 'col1' is now 1
assert_eq!(df.len(), 4);

// Filter by string foo,
df.filter_by_row(|row| row["col3"] != Datum::STR(&"foo".to_string()));
assert_eq!(df.len(), 2);

and a whole lot more..


Development


Contributing

All contributions are welcome. Contributors of this project are expected to treat all others with respect and dignity; acknowledging there will be differences of opinion and strive to provide a welcoming environment for others, regardless of skill level.

Additionally, all contributions, unless otherwise stated, will be given under the Unlicense and/or MIT licenses.

Dependencies

~12MB
~210K SLoC