Method pointToBytes

JSAT/src/jsat/io/JSATData.java:424–476

(DataPoint dp, double label, ByteArrayOutputStream byteOut)

            }
            
            @Override
            protected void pointToBytes(DataPoint dp, double label, ByteArrayOutputStream byteOut)
            {
                try
                {
                    DataOutputStream data_out = new DataOutputStream(byteOut);
                    fpStore.writeFP(dp.getWeight(), data_out);
                    for(int val : dp.getCategoricalValues())
                        data_out.writeInt(val);
                    if(type == DataWriter.DataSetType.CLASSIFICATION)
                        data_out.writeInt((int) label);
                    
                    Vec numericVals = dp.getNumericalValues();
                    
                    data_out.writeBoolean(numericVals.isSparse());
                    if(numericVals.isSparse())
                    {
                        if(type == DataWriter.DataSetType.REGRESSION)
                            data_out.writeInt(numericVals.nnz()+1);//+1 for the target value, which may actually be zero...
                        else
                            data_out.writeInt(numericVals.nnz());
                        
                        for(IndexValue iv : numericVals)
                        {
                            data_out.writeInt(iv.getIndex());
                            fpStore.writeFP(iv.getValue(), data_out);
                        }
                    }
                    else
                    {
                        for(int j = 0; j < numericVals.length(); j++)
                            fpStore.writeFP(numericVals.get(j), data_out);
                    }
                    
                    //append the target value
                    if(type == DataWriter.DataSetType.REGRESSION)
                    {
                        /*
                        * if dense, we only need to just add the extra double. If
                        * sparse, we do the index and then the double.
                        */
                        if (numericVals.isSparse())
                            data_out.writeInt(numericVals.length());
                        
                        fpStore.writeFP(label, data_out);
                    }
                    data_out.flush();
                }
                catch (IOException ex)
                {
                    Logger.getLogger(JSATData.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
        };
    }