StreamingSparseFeatures.cpp

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#include <shogun/features/StreamingSparseFeatures.h>
namespace shogun
{

template <class T>
CStreamingSparseFeatures<T>::CStreamingSparseFeatures() : CStreamingDotFeatures()
{
    set_read_functions();
    init();
}

template <class T>
CStreamingSparseFeatures<T>::CStreamingSparseFeatures(CStreamingFile* file,
             bool is_labelled,
             int32_t size)
    : CStreamingDotFeatures()
{
    set_read_functions();
    init(file, is_labelled, size);
}

template <class T>
CStreamingSparseFeatures<T>::~CStreamingSparseFeatures()
{
    parser.end_parser();
}

template <class T>
T CStreamingSparseFeatures<T>::get_feature(int32_t index)
{
    ASSERT(index>=0 && index<current_num_features);

    T ret=0;

    if (current_vector)
    {
        for (int32_t i=0; i<current_length; i++)
            if (current_vector[i].feat_index==index)
                ret += current_vector[i].entry;
    }

    return ret;
}

template <class T>
void CStreamingSparseFeatures<T>::reset_stream()
{
}

template <class T>
int32_t CStreamingSparseFeatures<T>::set_num_features(int32_t num)
{
    int32_t n=current_num_features;
    ASSERT(n<=num);
    current_num_features=num;
    return n;
}

template <class T>
void CStreamingSparseFeatures<T>::expand_if_required(float32_t*& vec, int32_t &len)
{
    int32_t dim = get_dim_feature_space();
    if (dim > len)
    {
        vec = SG_REALLOC(float32_t, vec, dim);
        memset(&vec[len], 0, (dim-len) * sizeof(float32_t));
        len = dim;
    }
}

template <class T>
void CStreamingSparseFeatures<T>::expand_if_required(float64_t*& vec, int32_t &len)
{
    int32_t dim = get_dim_feature_space();
    if (dim > len)
    {
        vec = SG_REALLOC(float64_t, vec, dim);
        memset(&vec[len], 0, (dim-len) * sizeof(float64_t));
        len = dim;
    }
}

template <class T>
T CStreamingSparseFeatures<T>::sparse_dot(T alpha, SGSparseVectorEntry<T>* avec, int32_t alen, SGSparseVectorEntry<T>* bvec, int32_t blen)
{
    T result=0;

    //result remains zero when one of the vectors is non existent
    if (avec && bvec)
    {
        if (alen<=blen)
        {
            int32_t j=0;
            for (int32_t i=0; i<alen; i++)
            {
                int32_t a_feat_idx=avec[i].feat_index;

                while ( (j<blen) && (bvec[j].feat_index < a_feat_idx) )
                    j++;

                if ( (j<blen) && (bvec[j].feat_index == a_feat_idx) )
                {
                    result+= avec[i].entry * bvec[j].entry;
                    j++;
                }
            }
        }
        else
        {
            int32_t j=0;
            for (int32_t i=0; i<blen; i++)
            {
                int32_t b_feat_idx=bvec[i].feat_index;

                while ( (j<alen) && (avec[j].feat_index < b_feat_idx) )
                    j++;

                if ( (j<alen) && (avec[j].feat_index == b_feat_idx) )
                {
                    result+= bvec[i].entry * avec[j].entry;
                    j++;
                }
            }
        }

        result*=alpha;
    }

    return result;
}

template <class T>
T CStreamingSparseFeatures<T>::dense_dot(T alpha, T* vec, int32_t dim, T b)
{
    ASSERT(vec);
    ASSERT(dim>=current_num_features);
    T result=b;

    int32_t num_feat=current_length;
    SGSparseVectorEntry<T>* sv=current_vector;

    if (sv)
    {
        for (int32_t i=0; i<num_feat; i++)
            result+=alpha*vec[sv[i].feat_index]*sv[i].entry;
    }

    return result;
}

template <class T>
float64_t CStreamingSparseFeatures<T>::dense_dot(const float64_t* vec2, int32_t vec2_len)
{
    ASSERT(vec2);
    if (vec2_len < current_num_features)
    {
        SG_ERROR("dimension of vec2 (=%d) does not match number of features (=%d)\n",
             vec2_len, current_num_features);
    }

    float64_t result=0;
    if (current_vector)
    {
        for (int32_t i=0; i<current_length; i++)
            result+=vec2[current_vector[i].feat_index]*current_vector[i].entry;
    }

    return result;
}

template <class T>
float32_t CStreamingSparseFeatures<T>::dense_dot(const float32_t* vec2, int32_t vec2_len)
{
    ASSERT(vec2);
    if (vec2_len < current_num_features)
    {
        SG_ERROR("dimension of vec2 (=%d) does not match number of features (=%d)\n",
             vec2_len, current_num_features);
    }

    float32_t result=0;
    if (current_vector)
    {
        for (int32_t i=0; i<current_length; i++)
            result+=vec2[current_vector[i].feat_index]*current_vector[i].entry;
    }

    return result;
}

template <class T>
void CStreamingSparseFeatures<T>::add_to_dense_vec(float64_t alpha, float64_t* vec2, int32_t vec2_len, bool abs_val)
{
    ASSERT(vec2);
    if (vec2_len < current_num_features)
    {
        SG_ERROR("dimension of vec (=%d) does not match number of features (=%d)\n",
             vec2_len, current_num_features);
    }

    SGSparseVectorEntry<T>* sv=current_vector;
    int32_t num_feat=current_length;

    if (sv)
    {
        if (abs_val)
        {
            for (int32_t i=0; i<num_feat; i++)
                vec2[sv[i].feat_index]+= alpha*CMath::abs(sv[i].entry);
        }
        else
        {
            for (int32_t i=0; i<num_feat; i++)
                vec2[sv[i].feat_index]+= alpha*sv[i].entry;
        }
    }
}

template <class T>
void CStreamingSparseFeatures<T>::add_to_dense_vec(float32_t alpha, float32_t* vec2, int32_t vec2_len, bool abs_val)
{
    ASSERT(vec2);
    if (vec2_len < current_num_features)
    {
        SG_ERROR("dimension of vec (=%d) does not match number of features (=%d)\n",
             vec2_len, current_num_features);
    }

    SGSparseVectorEntry<T>* sv=current_vector;
    int32_t num_feat=current_length;

    if (sv)
    {
        if (abs_val)
        {
            for (int32_t i=0; i<num_feat; i++)
                vec2[sv[i].feat_index]+= alpha*CMath::abs(sv[i].entry);
        }
        else
        {
            for (int32_t i=0; i<num_feat; i++)
                vec2[sv[i].feat_index]+= alpha*sv[i].entry;
        }
    }
}

template <class T>
int64_t CStreamingSparseFeatures<T>::get_num_nonzero_entries()
{
    return current_length;
}

template <class T>
float32_t CStreamingSparseFeatures<T>::compute_squared()
{
    ASSERT(current_vector);

    float32_t sq=0;

    for (int32_t i=0; i<current_length; i++)
        sq += current_vector[i].entry * current_vector[i].entry;

    return sq;
}

template <class T>
void CStreamingSparseFeatures<T>::sort_features()
{
    ASSERT(current_vector);

    SGSparseVectorEntry<T>* sf_orig=current_vector;
    int32_t len=current_length;

    int32_t* feat_idx=SG_MALLOC(int32_t, len);
    int32_t* orig_idx=SG_MALLOC(int32_t, len);

    for (int32_t i=0; i<len; i++)
    {
        feat_idx[i]=sf_orig[i].feat_index;
        orig_idx[i]=i;
    }

    CMath::qsort_index(feat_idx, orig_idx, len);

    SGSparseVectorEntry<T>* sf_new=SG_MALLOC(SGSparseVectorEntry<T>, len);

    for (int32_t i=0; i<len; i++)
        sf_new[i]=sf_orig[orig_idx[i]];

    // sanity check
    for (int32_t i=0; i<len-1; i++)
        ASSERT(sf_new[i].feat_index<sf_new[i+1].feat_index);

    // Copy new vector back to original
    for (int32_t i=0; i<len; i++)
        sf_orig[i]=sf_new[i];

    SG_FREE(orig_idx);
    SG_FREE(feat_idx);
    SG_FREE(sf_new);
}

template <class T>
CFeatures* CStreamingSparseFeatures<T>::duplicate() const
{
    return new CStreamingSparseFeatures<T>(*this);
}

template <class T>
int32_t CStreamingSparseFeatures<T>::get_num_vectors() const
{
    if (current_vector)
        return 1;
    return 0;
}

template <class T>
int32_t CStreamingSparseFeatures<T>::get_size()
{
    return sizeof(T);
}

template <class T> void CStreamingSparseFeatures<T>::set_vector_reader()
{
    parser.set_read_vector(&CStreamingFile::get_sparse_vector);
}

template <class T> void CStreamingSparseFeatures<T>::set_vector_and_label_reader()
{
    parser.set_read_vector_and_label
        (&CStreamingFile::get_sparse_vector_and_label);
}

#define GET_FEATURE_TYPE(f_type, sg_type)               \
template<> EFeatureType CStreamingSparseFeatures<sg_type>::get_feature_type() \
{                                   \
    return f_type;                          \
}

GET_FEATURE_TYPE(F_BOOL, bool)
GET_FEATURE_TYPE(F_CHAR, char)
GET_FEATURE_TYPE(F_BYTE, uint8_t)
GET_FEATURE_TYPE(F_BYTE, int8_t)
GET_FEATURE_TYPE(F_SHORT, int16_t)
GET_FEATURE_TYPE(F_WORD, uint16_t)
GET_FEATURE_TYPE(F_INT, int32_t)
GET_FEATURE_TYPE(F_UINT, uint32_t)
GET_FEATURE_TYPE(F_LONG, int64_t)
GET_FEATURE_TYPE(F_ULONG, uint64_t)
GET_FEATURE_TYPE(F_SHORTREAL, float32_t)
GET_FEATURE_TYPE(F_DREAL, float64_t)
GET_FEATURE_TYPE(F_LONGREAL, floatmax_t)
#undef GET_FEATURE_TYPE


template <class T>
void CStreamingSparseFeatures<T>::init()
{
    working_file=NULL;
    current_vector=NULL;
    current_length=-1;
    current_vec_index=0;
    current_num_features=-1;
}

template <class T>
void CStreamingSparseFeatures<T>::init(CStreamingFile* file,
                    bool is_labelled,
                    int32_t size)
{
    init();
    has_labels = is_labelled;
    working_file = file;
    parser.init(file, is_labelled, size);
}

template <class T>
void CStreamingSparseFeatures<T>::start_parser()
{
    if (!parser.is_running())
        parser.start_parser();
}

template <class T>
void CStreamingSparseFeatures<T>::end_parser()
{
    parser.end_parser();
}

template <class T>
bool CStreamingSparseFeatures<T>::get_next_example()
{
    bool ret_value;
    ret_value = (bool) parser.get_next_example(current_vector,
                           current_length,
                           current_label);

    if (!ret_value)
        return false;

    // Update number of features based on highest index
    for (int32_t i=0; i<current_length; i++)
    {
        if (current_vector[i].feat_index > current_num_features)
            current_num_features = current_vector[i].feat_index+1;
    }
    current_vec_index++;

    return true;
}

template <class T>
SGSparseVector<T> CStreamingSparseFeatures<T>::get_vector()
{
    current_sgvector.features=current_vector;
    current_sgvector.num_feat_entries=current_length;
    current_sgvector.vec_index=current_vec_index;

    return current_sgvector;
}

template <class T>
float64_t CStreamingSparseFeatures<T>::get_label()
{
    ASSERT(has_labels);

    return current_label;
}

template <class T>
void CStreamingSparseFeatures<T>::release_example()
{
    parser.finalize_example();
}

template <class T>
int32_t CStreamingSparseFeatures<T>::get_dim_feature_space() const
{
    return current_num_features;
}

template <class T>
    float32_t CStreamingSparseFeatures<T>::dot(CStreamingDotFeatures* df)
{
    SG_NOTIMPLEMENTED;
    return -1;
}

template <class T>
int32_t CStreamingSparseFeatures<T>::get_num_features()
{
    return current_num_features;
}

template <class T>
int32_t CStreamingSparseFeatures<T>::get_nnz_features_for_vector()
{
    return current_length;
}

template <class T>
EFeatureClass CStreamingSparseFeatures<T>::get_feature_class()
{
    return C_STREAMING_SPARSE;
}

template class CStreamingSparseFeatures<bool>;
template class CStreamingSparseFeatures<char>;
template class CStreamingSparseFeatures<int8_t>;
template class CStreamingSparseFeatures<uint8_t>;
template class CStreamingSparseFeatures<int16_t>;
template class CStreamingSparseFeatures<uint16_t>;
template class CStreamingSparseFeatures<int32_t>;
template class CStreamingSparseFeatures<uint32_t>;
template class CStreamingSparseFeatures<int64_t>;
template class CStreamingSparseFeatures<uint64_t>;
template class CStreamingSparseFeatures<float32_t>;
template class CStreamingSparseFeatures<float64_t>;
template class CStreamingSparseFeatures<floatmax_t>;
}