## dart_statistics 0.0.2

A dart library for statistics

## Usage #

A simple usage example:

``````import 'package:dart_statistics/dart_statistics.dart';

void main() {
// We expect a fair die
final expected = <double>[2, 2, 2, 2, 2, 2];

// Looks pretty unfair...
final observed = <double>[6, 3, 3, 0, 0, 0];

// Reduction in degrees of freedom is 1, since knowing 5 categories determines the 6th
final reduction = 1;

var probability = chiSquaredTest(
observed,
expected,
degreesOfFreedomReduction: reduction,
).probability;
print(probability);
assert(probability == 0.010362);
// Gives 0.010362, which indicates that it's unlikely the die is fair

// However, something a little more likely
observed.clear();
observed.addAll([1, 2, 4, 4, 2, 1]);
probability = chiSquaredTest(
observed,
expected,
degreesOfFreedomReduction: reduction,
).probability;
print(probability);
assert(probability == 0.414881);
// Gives back 0.415881, which is indicates that they did come from the same distribution (by most statistical standards)
}

``````

## Features and bugs #

Please file feature requests and bugs on github, I will gladly accept pull requests and changes, this is not a library that I'm actively developing. If anyone would like to take over the library that is also fine.

## 0.0.2 #

• Changed optional parameter of degrees of freedom reduction to be 1, since a lot of applications will require the frequencies / probabilities to sum to one. And a reduction of 0 would cause an exception anyways

## Use this package as a library

### 1. Depend on it

``````
dependencies:
dart_statistics: ^0.0.2

``````

### 2. Install it

You can install packages from the command line:

with pub:

``````
\$ pub get

``````

with Flutter:

``````
\$ flutter pub get

``````

Alternatively, your editor might support `pub get` or `flutter pub get`. Check the docs for your editor to learn more.

### 3. Import it

Now in your Dart code, you can use:

``````
import 'package:dart_statistics/dart_statistics.dart';
``````
 Popularity: Describes how popular the package is relative to other packages. [more] 45 Health: Code health derived from static analysis. [more] 100 Maintenance: Reflects how tidy and up-to-date the package is. [more] 90 Overall: Weighted score of the above. [more] 70

We analyzed this package on Mar 30, 2020, and provided a score, details, and suggestions below. Analysis was completed with status completed using:

• Dart: 2.7.1
• pana: 0.13.6

#### Health suggestions

Format `lib/src/chi_squared_test.dart`.

Run `dartfmt` to format `lib/src/chi_squared_test.dart`.

#### Maintenance suggestions

Package is pre-v0.1 release. (-10 points)

While nothing is inherently wrong with versions of `0.0.*`, it might mean that the author is still experimenting with the general direction of the API.

Maintain an example.

None of the files in the package's `example/` directory matches known example patterns.

Common filename patterns include `main.dart`, `example.dart`, and `dart_statistics.dart`. Packages with multiple examples should provide `example/README.md`.