analyticsLibrary.Core 2.0.0-beta.pr-6.2

analyticsLibrary

A family of focused .NET 8 packages for reading and writing CSV and fixed-width files, performing statistical operations, running sort and search algorithms, and working with Excel, Access, and Hadoop data sources.

Version 2.0.0 is a breaking-change release. The monolithic analyticsLibrary 1.x package has been split into focused packages. SQL Server, Oracle, SAS, and Sybase provider support has been removed. See the Migration Guide below.

Table of Contents

• Package Overview
• Namespace Reference
• Installation
• Quick Starts
• Functionality
• Repository Layout
• Build and Test
• Release Process
• Contributing
• Migration Guide

Package Overview

Platform note: analyticsLibrary.Excel and analyticsLibrary.Access depend on System.Data.OleDb, which is Windows-only at runtime. These packages compile on all platforms but can only execute on Windows.

Namespace Reference

Installation

Install only the packages you need for a leaner dependency graph.

# Core CSV and data helpers
dotnet add package analyticsLibrary.Core

# Sort and search algorithms
dotnet add package analyticsLibrary.Algorithms

# Statistics
dotnet add package analyticsLibrary.Statistics

# Excel file operations (Windows runtime only)
dotnet add package analyticsLibrary.Excel

# Access database support (Windows runtime only)
dotnet add package analyticsLibrary.Access

# Hadoop/ODBC support
dotnet add package analyticsLibrary.Hadoop

# Everything (transition metapackage)
dotnet add package analyticsLibrary

Quick Starts

Read a CSV file

using analyticsLibrary.Core;

var file = new csv("data.csv");
foreach (var row in file.data)
{
    Console.WriteLine(string.Join(", ", row.values));
}

Write a CSV file

using analyticsLibrary.Core;

var header = new[] { "Name", "Score" };
var rows = new[]
{
    new object[] { "Alice", 95 },
    new object[] { "Bob",   87 },
};
rows.writeCsv("output.csv", header, ',');

Standard deviation and normalization

using analyticsLibrary.Statistics;

double[] scores = { 70, 80, 85, 90, 95 };
double stddev = scores.standardDeviation();
double[] normalized = scores.normalize();  // maps min to 0.0, max to 1.0

Sort a list

using analyticsLibrary.Algorithms;

int[] values = { 5, 3, 8, 1, 9 };
int[] sorted = values.mergeSort();           // ascending
int[] desc   = values.quickSort(descending: true);  // descending

Parse a SAS date string

using analyticsLibrary.Core;

DateTime? date = "01JAN2020:00:00:00.000".fromSasEpochDate();

Functionality

CSV and Fixed-Width Files (analyticsLibrary.Core)

• Read CSV files with configurable delimiters and optional headers via the csv class.
• Write IEnumerable<object[]> to CSV using writeCsv extension methods.
• Parse individual CSV lines with fromCsv and serialize object arrays with toCsv.
• Read fixed-width files with fixedWidthFile and fixedWidthFileStream.
• loopDateRange iterates over a date range with configurable step intervals.

Statistics (analyticsLibrary.Statistics)

All methods are extension methods on double[] or IEnumerable<double>:

Algorithms (analyticsLibrary.Algorithms)

• mergeSort<T>() — stable recursive merge sort; supports ascending and descending order for int, double, float, decimal, and string.
• quickSort<T>() — in-place quick sort; same type support as merge sort.
• sorting.pickFunction<T>() — returns the comparison delegate for a given type; useful for supplying a custom comparator.

Core Helpers (analyticsLibrary.Core)

• dataTypeHelper.dataTypeFromString(string) — maps SQL/ODBC type name strings (e.g. "varchar", "int") to dataTypeEnum values.
• analytics — compress(), titleCase(), wordReplace() string extension methods.
• extensions.fromSasEpochDate() — parses a SAS datetime string in ddMMMyyyy:hh:mm:ss.fff format.

Excel (analyticsLibrary.Excel, Windows)

• Read and write Excel workbooks and individual worksheets as DataSet/DataTable.
• Target individual cells in an existing workbook.

Access (analyticsLibrary.Access, Windows)

• Open and query Access .mdb/.accdb database files via OleDb.

Hadoop (analyticsLibrary.Hadoop)

• Read data from Hadoop clusters via an ODBC connection string.

Repository Layout

.github/
  workflows/
    ci.yml        # PR: build, test, pack, upload beta artifacts
    release.yml   # Tag/dispatch: build, test, pack, deploy to NuGet
src/
  analyticsLibrary.Core/
  analyticsLibrary.Algorithms/
  analyticsLibrary.Statistics/
  analyticsLibrary.Excel/
  analyticsLibrary.Access/
  analyticsLibrary.Hadoop/
  analyticsLibrary/           # transition metapackage
  analyticsLibraryInstaller/
  release files/
tests/
  analyticsLibrary.Core.Tests/
  analyticsLibrary.Statistics.Tests/
  analyticsLibrary.Algorithms.Tests/
docs/
  epics/
    epic-001-remodel.plan.md
Directory.Packages.props      # centralized NuGet version management
Analytics Library.sln

Build and Test

Requirements: .NET 8 SDK or later.

# Restore dependencies
dotnet restore

# Build all projects (Release)
dotnet build -c Release

# Run all unit tests
dotnet test -c Release

# Pack NuGet packages into ./nupkgs
dotnet pack -c Release -o ./nupkgs

Release Process

Beta packages (pull requests)

Opening or updating a pull request against main triggers ci.yml. The workflow builds, tests, packs beta packages versioned 2.0.0-beta.pr-<pr>.<run>, and uploads them as workflow artifacts. Beta packages are only pushed to NuGet.org when the NUGET_API_KEY secret is available and the PR is not from a fork.

Release packages

Push a version tag (e.g. v2.0.0) or trigger release.yml manually via workflow dispatch. The workflow:

1. Builds and tests the solution from the tagged commit.
2. Packs all seven packages.
3. Verifies all expected .nupkg files are present.
4. Deploys to NuGet.org under the nuget-release GitHub Environment, which requires explicit approval before the deploy step runs.

Store the NuGet API key as a repository secret named NUGET_API_KEY. Never commit credentials.

Contributing

• Keep packages focused. Core must not depend on Excel, Access, Hadoop, or provider-specific packages.
• Add tests for all new public logic before submitting a PR. Tests live in tests/.
• EPPlus is intentionally pinned to 5.8.14 (the last release under the PolyForm Noncommercial License). EPPlus 6+ requires a commercial license. Do not upgrade without a license review.
• System.Data.OleDb and System.Data.Access are Windows-only at runtime. Keep them isolated to analyticsLibrary.Excel and analyticsLibrary.Access.
• Package versions are centrally managed in Directory.Packages.props. Add new dependencies there first.

Migration Guide

From analyticsLibrary 1.x to 2.0.0

Removed packages and namespaces

Steps to migrate

1. Remove analyticsLibrary 1.x from your project.
2. Add the focused 2.x packages you need (see Installation).
3. Update using directives to the new namespaces:
   • analyticsLibrary.library → analyticsLibrary.Core
   • analyticsLibrary.cs → analyticsLibrary.Algorithms
   • analyticsLibrary.statistics → analyticsLibrary.Statistics
   • analyticsLibrary.excelLibrary → analyticsLibrary.Excel
   • analyticsLibrary.access → analyticsLibrary.Access
   • analyticsLibrary.hadoop → analyticsLibrary.Hadoop
4. Remove any references to the deleted namespaces (sqlDb, oracle, sas, sybase) and their package references listed above.
5. If you called fromSasDate(), rename it to fromSasEpochDate().

Target framework: Projects must target net8.0 or later. netcoreapp3.1 is no longer supported.