/// <summary>
/// Constructor
/// </summary>
/// <param name="env">environment</param>
/// <param name="modelStream">stream</param>
/// <param name="output">name of the output column</param>
/// <param name="outputIsFloat">output is a gloat (true) or a vector of floats (false)</param>
/// <param name="conc">number of concurrency threads</param>
/// <param name="features">features name</param>
public ValueMapperPredictionEngineFloat(IHostEnvironment env, Stream modelStream,
string output = "Probability", bool outputIsFloat = true, int conc = 1,
string features = "Features")
{
_env = env;
if (_env == null)
{
throw Contracts.Except("env must not be null");
}
var inputs = new FloatVectorInput[0];
var view = ComponentCreation.CreateStreamingDataView <FloatVectorInput>(_env, inputs);
long modelPosition = modelStream.Position;
_predictor = ComponentCreation.LoadPredictorOrNull(_env, modelStream);
if (_predictor == null)
{
throw _env.Except("Unable to load a model.");
}
modelStream.Seek(modelPosition, SeekOrigin.Begin);
_transforms = ComponentCreation.LoadTransforms(_env, modelStream, view);
if (_transforms == null)
{
throw _env.Except("Unable to load a model.");
}
var data = _env.CreateExamples(_transforms, features);
if (data == null)
{
throw _env.Except("Cannot create rows.");
}
var scorer = _env.CreateDefaultScorer(data, _predictor);
if (scorer == null)
{
throw _env.Except("Cannot create a scorer.");
}
_valueMapper = new ValueMapperFromTransformFloat <VBuffer <float> >(_env,
scorer, features, output, conc: conc);
if (_valueMapper == null)
{
throw _env.Except("Cannot create a mapper.");
}
if (outputIsFloat)
{
_mapper = _valueMapper.GetMapper <VBuffer <float>, float>();
_mapperVector = null;
}
else
{
_mapper = null;
_mapperVector = _valueMapper.GetMapper <VBuffer <float>, VBuffer <float> >();
}
}
public void Dispose()
{
_valueMapper.Dispose();
_valueMapper = null;
}
