Home
statistics-calculator-toolkit
Small, dependency-free libraries for the mean, sum of squared deviations, population and sample variance, population and sample standard deviation, coefficient of variation and relative standard deviation (RSD).
Every language exposes the same operations, uses the same numerically careful algorithm, validates input the same way and is tested against the same known values. See the API contract for names, behaviour and floating-point notes.
Install
| language | registry | install | docs |
|---|---|---|---|
| Python | PyPI | pip install sdtoolkit |
Python guide |
| JavaScript / TypeScript | npm | npm install @rameshxyz/sdtoolkit |
README |
| Rust | crates.io | cargo add sdtoolkit |
README, docs.rs |
| Go | Go modules | go get github.com/Ramesh-xyz/statistics-calculator-toolkit/go/sdtoolkit |
README, pkg.go.dev |
| R | CRAN | install.packages("sdcalc") |
README |
| Java / Kotlin | Maven Central | io.github.ramesh-xyz:sdtoolkit |
README |
| C# / .NET | NuGet | dotnet add package SdToolkit |
README |
| Ruby | RubyGems | gem install sdtoolkit |
README |
| PHP | Packagist | composer require ramesh-xyz/sdtoolkit |
README |
| Dart / Flutter | pub.dev | dart pub add sdtoolkit |
README |
Each package is released independently from a git tag; the changelog lists what has shipped. Until a language’s first release, install it from the repository directory linked above.
Example
The classic dataset 2, 4, 4, 4, 5, 5, 7, 9 gives the same results in every
language:
| statistic | value |
|---|---|
| mean | 5 |
| sum of squares | 32 |
| population variance / standard deviation | 4 / 2 |
| sample variance / standard deviation | 4.571428571428571 / 2.138089935299395 |
| RSD, sample / population | 42.76 % / 40 % |
Guides
- Standard deviation: what it measures and how to read it
- Variance: the average squared deviation
- Sample vs population: when to divide by n − 1
- Relative standard deviation: comparing spread across scales
- Outliers: how single extreme values inflate the SD
Source and issues
Code, issues and pull requests: github.com/Ramesh-xyz/statistics-calculator-toolkit. For an interactive calculator, see standarddeviationcalculator.net.