Update README.md

Author: 0x1mason

README.md

@@ -1,2 +1,193 @@
-# THIS REPOSITORY HAS MOVED
-https://github.com/GribApiDotNet/GribApi.NET
+# GribApi.NET
+
+## What it is
+GribApi.NET is a C# wrapper around the [European Centre for Medium Range Weather Forecasting's](http://www.ecmwf.int/) powerful [grib_api](https://software.ecmwf.int/wiki/display/GRIB/Home), a C library for reading, writing, and converting GRIB1 and GRIB2 files. 
+
+GRIB is a format commonly used in meteorology to store weather data. GribApi.NET makes it easy to encode and decode these data by providing access to both GRIB editions through a set of [GRIB API keys](https://software.ecmwf.int/wiki/display/GRIB/GRIB%20API%20keys). GribApi.NET and grib_api are licensed under the friendly [Apache License 2.0](http://www.apache.org/licenses/LICENSE-2.0).
+
+Special thanks to John L'Heureux, Meteorological Data Analyst at aWhere, Inc., for his contributions as scientific advisor.
+
+#### Features
+* Read and write GRIB 1 and 2 messages
+* Easy to understand API
+* Supports x86, x64, and "All CPU"
+* Thread safe
+* JPEG and PNG compression support
+* Multi-field support
+
+#### GRIB Tools
+You can also use grib_api via CLI. Checkout the GRIB tools package on [Chocolatey](https://chocolatey.org/packages/grib-tools). At the very least, you'll find it very helpful for debugging.
+
+--------------------------
+
+## Docs
+The documentation is very much a WIP, but you'll find [grib_api's wiki](https://software.ecmwf.int/wiki/display/GRIB/Home), helpful.
+
+* [Key Concepts](https://github.com/0x1mason/GribApi.NET/blob/master/docs/KeyConcepts.md)
+* [Example Key Dump](https://github.com/0x1mason/GribApi.NET/blob/master/docs/TypicalKeyDump.md)
+
+--------------------------
+
+## Usage
+Make sure you have the [MSVC 2015 redistributables](https://www.microsoft.com/en-us/download/details.aspx?id=48145) installed. If you don't, you can use `chocolatey`, 
+```shell
+C:\> choco install vcredist2015
+```
+
+Install [GribApi.NET using Nuget](https://www.nuget.org/packages/Grib.Api). From Package Manager Console run
+```shell
+PM> Install-Package Grib.Api 
+```
+
+#### Troubleshooting
+In general, GribApi.NET should "just work". In rare cases, GribApi.NET may have difficulty locating the `Grib.Api` directory, which contains a number of dependencies.
+
+To solve this problem, set the environment variable `GRIB_API_DIR_ROOT` before calling GribApi.NET for the first time. The value should be the directory *containing* the `Grib.Api` directory. E.g., for `C:\Some\Path\Grib.Api`, set:
+```csharp
+Environment.SetEnvironmentVariable("GRIB_API_DIR_ROOT", "C:\\Some\\Path", EnvironmentVariableTarget.Process);
+```
+
+### Examples
+
+#### Getting grid information from a GRIB message:
+```csharp
+	using (GribFile file = new GribFile("mygrib.grb"))
+	{
+		GribMessage msg = file.First();
+
+		Console.WriteLine("Grid Type: " + msg.GridType);
+		
+		double latInDegrees = msg["latitudeOfFirstGridPoint"].AsDouble();
+		// GribApi.NET normalizes the coordinate values to degrees. This follows the best practice advised by ECMWF.
+		
+		// values are also accessible as strings
+		Console.WriteLine("latitudeOfFirstGridPointInDegrees = " + msg["latitudeOfFirstGridPoint"].AsString());
+	}
+```
+
+#### Iterating multiple messages:
+```csharp
+	using (GribFile file = new GribFile("mygrib.grb"))
+	{
+		foreach (GribMessage msg in file)
+		{
+			// do something
+		}
+	}
+```
+
+#### Iterating lat/lon/value:
+```csharp
+
+	GribMessage msg = gribFile.First();
+	
+	// the values in GeoSpatialValues are calculated by grid type
+	foreach (GeoSpatialValue val in msg.GeoSpatialValues)
+	{
+		if (val.IsMissing) { continue; }
+
+		Console.WriteLine("Lat: {0} Lon: {1} Val: {2}", val.Latitude, val.Longitude, val.Value);
+	}
+```
+
+#### Cherry-picking messages by parameter name
+```csharp
+	using(GribFile file = new GribFile(@".\TestData\Pacific.wind.7days.grb"))
+	{
+		var vComp = file.Where(m => m.Name.Contains("V-component of wind m s**-1")).First();
+
+		foreach (var val in vComp.GeoSpatialValues)
+		{
+			Console.WriteLine("Lat: {0} Lon: {1} Val: {2}", val.Latitude, val.Longitude, val.Value);
+		}
+	}
+```
+
+#### Key dump:
+```csharp
+	using (GribFile file = new GribFile("mygrib.grb"))
+	{
+		GribMessage msg = file.First();
+		
+		foreach (var msg in file)
+		{
+			foreach (var key in msg)
+			{
+				Console.WriteLine("Key: {0}, Value: {1}", key.Name, key.Value.AsString());
+			}
+		}
+	}
+```
+
+#### Getting raw data:
+```csharp
+
+	GribMessage msg = gribFile.First();
+	double[] rawValues;
+	
+	// a copy of the raw values stored in the message
+	msg.Values(out rawValues);
+```
+
+#### Editing a single message and saving to a new file:
+```csharp
+	string outPath = "out.grb";
+	string readPath = "some.grb";
+	
+	using (GribFile readFile = new GribFile(readPath))
+	{
+		Console.WriteLine("Writing 1 message from {0} to {1}", readPath, outPath);
+
+		var msg = readFile.First();
+		msg["latitudeOfFirstGridPoint"].AsDouble(42);
+		GribFile.Write(outPath, msg);
+	}
+```
+
+#### Appending multiple messages to an existing file:
+```csharp
+	using (GribFile readFile = new GribFile(readPath))
+	{                
+		Console.WriteLine("Appending {0} messages from {1} to {2}", readFile.MessageCount, readPath, outPath);
+
+		GribFile.Write(outPath, readFile as IEnumerable<GribMessage>, FileMode.Append);
+		// or, more simply:
+		//   GribFile.Write(outPath, readFile, FileMode.Append);
+	}
+```
+
+For more examples, checkout the tests.
+
+--------------------------
+
+## Building
+The current build is only designed for Windows and Visual Studio. I am eager to get it converted to CMake and make it cross-platform. Even a consistent build using make under msys2 would be great. I'd love some help doing this. :)
+
+First, install the Nuget packages (this assumes you have nuget on PATH):
+```shell
+nuget install NUnit -Version 2.6.4 -O src\GribApi.NET\packages\
+```
+
+Install [NUnit 2.6.4](http://www.nunit.org/). Then run:
+```shell
+build\build_gribapi.cmd [build|rebuild] [VS version, 11|12|14] [Debug|Release] [nuget package version]
+```
+
+E.g., to build with Visual Studio 2013 (VS version 12):
+```shell
+build\build_gribapi.cmd build 12 Debug
+```
+
+### Running SWIG
+Most of the interop interfaces are generated using `SWIG` and included in the repository. You shouldn't need to create them. However, if you want to generate the interfaces yourself, you'll need `SWIG` installed and available on PATH. Then run `build/swig_gen.cmd`.
+
+### Running Tests
+1. Install [NUnit](http://www.nunit.org/) and expose it on PATH.
+2. Run `build/run_tests <architecture> <configuration> [optional "1" to break the tests on start]`, e.g.
+```shell
+build/run_tests x64 Debug
+```
+or
+```shell
+build/run_tests x86 Debug 1
+```