HDF5 C++ API Reference Manual

 

 

 

H5DataSet.h

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// Class DataSet inherits from AbstractDs and provides accesses to a dataset.

#ifndef _H5DataSet_H
#define _H5DataSet_H

#ifndef H5_NO_NAMESPACE
namespace H5 {
#endif

class H5_DLLCPP DataSet : public H5Object, public AbstractDs {
   public:
        // Close this dataset.
        virtual void close();

        // Extends the dataset with unlimited dimension.
        void extend( const hsize_t* size ) const;

        // Fills a selection in memory with a value
        void fillMemBuf(const void *fill, DataType& fill_type, void *buf, DataType& buf_type, DataSpace& space);
        // Fills a selection in memory with zero
        void fillMemBuf(void *buf, DataType& buf_type, DataSpace& space);

        // Gets the creation property list of this dataset.
        DSetCreatPropList getCreatePlist() const;

        // Returns the address of this dataset in the file.
        haddr_t getOffset() const;

        // Gets the dataspace of this dataset.
        virtual DataSpace getSpace() const;

        // Determines whether space has been allocated for a dataset.
        void getSpaceStatus(H5D_space_status_t& status) const;

        // Returns the amount of storage size required for this dataset.
        virtual hsize_t getStorageSize() const;

        // Returns the in memory size of this attribute's data.
        virtual size_t getInMemDataSize() const;

        // Returns the number of bytes required to store VL data.
        hsize_t getVlenBufSize( DataType& type, DataSpace& space ) const;

        // Reclaims VL datatype memory buffers.
        static void vlenReclaim(const DataType& type, const DataSpace& space, const DSetMemXferPropList& xfer_plist, void* buf );
        static void vlenReclaim(void *buf, const DataType& type, const DataSpace& space = DataSpace::ALL, const DSetMemXferPropList& xfer_plist = DSetMemXferPropList::DEFAULT);

        // Reads the data of this dataset and stores it in the provided buffer.
        // The memory and file dataspaces and the transferring property list
        // can be defaults.
        void read( void* buf, const DataType& mem_type, const DataSpace& mem_space = DataSpace::ALL, const DataSpace& file_space = DataSpace::ALL, const DSetMemXferPropList& xfer_plist = DSetMemXferPropList::DEFAULT ) const;
        void read( H5std_string& buf, const DataType& mem_type, const DataSpace& mem_space = DataSpace::ALL, const DataSpace& file_space = DataSpace::ALL, const DSetMemXferPropList& xfer_plist = DSetMemXferPropList::DEFAULT ) const;

        // Writes the buffered data to this dataset.
        // The memory and file dataspaces and the transferring property list
        // can be defaults.
        void write( const void* buf, const DataType& mem_type, const DataSpace& mem_space = DataSpace::ALL, const DataSpace& file_space = DataSpace::ALL, const DSetMemXferPropList& xfer_plist = DSetMemXferPropList::DEFAULT ) const;
        void write( const H5std_string& buf, const DataType& mem_type, const DataSpace& mem_space = DataSpace::ALL, const DataSpace& file_space = DataSpace::ALL, const DSetMemXferPropList& xfer_plist = DSetMemXferPropList::DEFAULT ) const;

        // Iterates the selected elements in the specified dataspace - not implemented in C++ style yet
        int iterateElems( void* buf, const DataType& type, const DataSpace& space, H5D_operator_t op, void* op_data = NULL );

        // Retrieves the type of object that an object reference points to.
        H5G_obj_t getObjType(void *ref, H5R_type_t ref_type = H5R_OBJECT) const;

        // Retrieves a dataspace with the region pointed to selected.
        DataSpace getRegion(void *ref, H5R_type_t ref_type = H5R_DATASET_REGION) const;

        // Returns this class name
        virtual H5std_string fromClass () const { return("DataSet"); }

        // Creates a dataset by way of dereference.
        DataSet(H5Object& obj, void* ref, H5R_type_t ref_type = H5R_OBJECT);
        DataSet(H5File& h5file, void* ref, H5R_type_t ref_type = H5R_OBJECT);
        DataSet(Attribute& attr, void* ref, H5R_type_t ref_type = H5R_OBJECT);

        // Default constructor.
        DataSet();

        // Copy constructor.
        DataSet( const DataSet& original );

        // Creates a copy of an existing DataSet using its id.
        DataSet(const hid_t existing_id);

        // Gets the dataset id.
        virtual hid_t getId() const;

        // Destructor: properly terminates access to this dataset.
        virtual ~DataSet();

   protected:
        // Sets the dataset id.
        virtual void p_setId(const hid_t new_id);

   private:
        hid_t id;       // HDF5 dataset id

        // This function contains the common code that is used by
        // getTypeClass and various API functions getXxxType
        // defined in AbstractDs for generic datatype and specific
        // sub-types
        virtual hid_t p_get_type() const;

        // Reads variable or fixed len strings from this dataset.
        void p_read_fixed_len(const hid_t mem_type_id, const hid_t mem_space_id, const hid_t file_space_id, const hid_t xfer_plist_id, H5std_string& strg) const;
        void p_read_variable_len(const hid_t mem_type_id, const hid_t mem_space_id, const hid_t file_space_id, const hid_t xfer_plist_id, H5std_string& strg) const;
};
#ifndef H5_NO_NAMESPACE
}
#endif
#endif

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