.NET library for reading and writing Weka attribute-relation file format (ARFF) files
- Read and write ARFF files
- Supports relational attributes
- Supports sparse instances
- Supports instance weights
- Proper quoting and escaping of special characters
Reading ARFF files:
using (ArffReader arffReader = new ArffReader("glass.arff"))
{
ArffHeader header = arffReader.ReadHeader();
while (arffReader.ReadInstance() is object?[] instance)
{
// process instance
}
}Reading all instances at a time:
object?[][] instances = arffReader.ReadAllInstances();Writing ARFF files:
using (ArffWriter arffWriter = new ArffWriter("iris.arff"))
{
arffWriter.WriteRelationName("iris");
arffWriter.WriteAttribute(new ArffAttribute("sepallength", ArffAttributeType.Numeric));
arffWriter.WriteAttribute(new ArffAttribute("sepalwidth", ArffAttributeType.Numeric));
arffWriter.WriteAttribute(new ArffAttribute("petallength", ArffAttributeType.Numeric));
arffWriter.WriteAttribute(new ArffAttribute("petalwidth", ArffAttributeType.Numeric));
arffWriter.WriteAttribute(new ArffAttribute("class", ArffAttributeType.Nominal("Iris-setosa", "Iris-versicolor", "Iris-virginica")));
arffWriter.WriteInstance(new object?[] { 5.1, 3.5, 1.4, 0.2, 0 });
}Instances are represented as object?[] whose elements correspond to the attribute values. ARFF attribute types are mapped to .NET types as follows:
| ARFF attribute type | .NET type |
|---|---|
| numeric, integer, real | double |
| nominal | int |
| string | string |
| date | DateTime |
| relational | object?[][] |
Missing values are represented as null. Sparse instances are represented as normal (dense) instances in memory.