|
tatami
C++ API for different matrix representations
|
Extract an element of the target dimension in sparse form with an oracle. More...
#include <Extractor.hpp>

Public Member Functions | |
| SparseRange< Value_, Index_ > | fetch (Value_ *value_buffer, Index_ *index_buffer) |
| virtual SparseRange< Value_, Index_ > | fetch (Index_ i, Value_ *value_buffer, Index_ *index_buffer)=0 |
Extract an element of the target dimension in sparse form with an oracle.
| Value_ | Data value type, should be numeric. |
| Index_ | Row/column index type, should be integer. |
|
inline |
| [out] | value_buffer | Pointer to an array with enough space for at least N values, where N is defined as described for MyopicDenseExtractor::fetch(). |
| [out] | index_buffer | Pointer to an array with enough space for at least N indices, where N is defined as described for MyopicDenseExtractor::fetch(). |
If Options::sparse_extract_value = false during construction of this instance, value_buffer is ignored and SparseRange::value is set to NULL in the output.
If Options::sparse_extract_value = true and SparseRange::value is the same as value_buffer, this means that value_buffer has been filled with the values of the structural non-zero elements of the i-th dimension element.
If Options::sparse_extract_value = true and SparseRange::value is not the same as value_buffer, it should refer to another array of length SparseRange::number. This array should be valid for the lifetime of the Matrix object used to construct this MyopicSparseExtractor. Similarly, the contents should not change for the lifetime of the Matrix. In this situation, no guarantees are provided for the contents of value_buffer.
If Options::sparse_extract_index was set to false during construction of this instance, index_buffer is ignored and SparseRange::index is set to NULL in the output.
If Options::sparse_extract_index = true and SparseRange::index is the same as index_buffer, this means that index_buffer has been filled with the indices of the structural non-zero elements of the i-th dimension element.
If Options::sparse_extract_index = true and SparseRange::index is not the same as index_buffer, it should refer to another array of length SparseRange::number. This array should be valid for the lifetime of the Matrix object used to construct this MyopicSparseExtractor. Similarly, the contents should not change for the lifetime of the Matrix. In this situation, no guarantees are provided for the contents of index_buffer.
|
pure virtual |
This overload is intended for developers only. It introduces the i argument so that the signature is the same as that of MyopicSparseExtractor::fetch(). This makes it easier to define MyopicSparseExtractor and OracularSparseExtractor subclasses from a single template, avoiding code duplication that would otherwise occur when defining methods with and without i. Of course, implementations are expected to ignore i in oracle-aware extraction.
Other than the extra i argument, all other behaviors of the two overloads are the same. To avoid confusion, most users should just use the fetch() overload that does not accept i, given that the value of i is never actually used.
| i | Ignored, only provided for consistency with MyopicSparseExtractor::fetch(). | |
| [out] | value_buffer | Pointer to an array with enough space for at least N values, where N is defined as described for MyopicDenseExtractor::fetch(). |
| [out] | index_buffer | Pointer to an array with enough space for at least N indices, where N is defined as described for MyopicDenseExtractor::fetch(). |
SparseRange object describing the contents of the next dimension element, see the other fetch() overload for details. Implemented in tatami::PseudoOracularSparseExtractor< Value_, Index_ >.