HDF5 C++ API Reference Manual

 

 

 

H5DataType.h

Go to the documentation of this file.

// C++ informative line for the emacs editor: -*- C++ -*-
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the files COPYING and Copyright.html.  COPYING can be found at the root   *
 * of the source code distribution tree; Copyright.html can be found at the  *
 * root level of an installed copy of the electronic HDF5 document set and   *
 * is linked from the top-level documents page.  It can also be found at     *
 * http://hdfgroup.org/HDF5/doc/Copyright.html.  If you do not have          *
 * access to either file, you may request a copy from help@hdfgroup.org.     *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#ifndef _H5DataType_H
#define _H5DataType_H

#ifndef H5_NO_NAMESPACE
namespace H5 {
#endif

class H5_DLLCPP DataType : public H5Object {
   public:
        // Creates a datatype given its class and size
        DataType( const H5T_class_t type_class, size_t size );

        // Copy constructor: makes a copy of the original object
        DataType( const DataType& original );

        // Creates a datatype by way of dereference.
        DataType(IdComponent& obj, void* ref);

        // Closes this datatype.
        virtual void close();

        // Copies an existing datatype to this datatype object.
        void copy(const DataType& like_type);

        // Copies the datatype of dset to this datatype object.
        void copy(const DataSet& dset);

        // Returns the datatype class identifier.
        H5T_class_t getClass() const;

        // Commits a transient datatype to a file; this datatype becomes
        // a named datatype which can be accessed from the location.
        void commit( H5File& loc, const char* name);
        void commit( H5File& loc, const H5std_string& name);
        void commit( H5Object& loc, const char* name);
        void commit( H5Object& loc, const H5std_string& name);

        // Determines whether this datatype is a named datatype or
        // a transient datatype.
        bool committed() const;

        // Finds a conversion function that can handle the conversion
        // this datatype to the given datatype, dest.
        H5T_conv_t find( const DataType& dest, H5T_cdata_t **pcdata ) const;

        // Converts data from between specified datatypes.
        void convert( const DataType& dest, size_t nelmts, void *buf, void *background, const PropList& plist=PropList::DEFAULT) const;

        // Assignment operator
        DataType& operator=( const DataType& rhs );

        // Determines whether two datatypes are the same.
        bool operator==(const DataType& compared_type ) const;

        // Locks a datatype.
        void lock() const;

        // Returns a pointer to the current global overflow function.
        H5T_overflow_t getOverflow(void) const;

        // Sets the overflow handler to a specified function.
        void setOverflow(H5T_overflow_t func) const;

        // Returns the size of a datatype.
        size_t getSize() const;

        // Returns the base datatype from which a datatype is derived.
        // Note: not quite right for specific types yet???
        DataType getSuper() const;

        // Registers a conversion function.
        void registerFunc(H5T_pers_t pers, const char* name, const DataType& dest, H5T_conv_t func ) const;
        void registerFunc(H5T_pers_t pers, const H5std_string& name, const DataType& dest, H5T_conv_t func ) const;

        // Removes a conversion function from all conversion paths.
        void unregister( H5T_pers_t pers, const char* name, const DataType& dest, H5T_conv_t func ) const;
        void unregister( H5T_pers_t pers, const H5std_string& name, const DataType& dest, H5T_conv_t func ) const;

        // Tags an opaque datatype.
        void setTag( const char* tag ) const;
        void setTag( const H5std_string& tag ) const;

        // Gets the tag associated with an opaque datatype.
        H5std_string getTag() const;

        // Checks whether this datatype contains (or is) a certain type class.
        bool detectClass(H5T_class_t cls) const;

        // Checks whether this datatype is a variable-length string.
        bool isVariableStr() const;

        // Creates a reference to a named HDF5 object or to a dataset region
        // in this object.
        void* Reference(const char* name, DataSpace& dataspace, H5R_type_t ref_type = H5R_DATASET_REGION) const; // will be obsolete

        // Creates a reference to a named HDF5 object in this object.
        void* Reference(const char* name) const; // will be obsolete
        void* Reference(const H5std_string& name) const; // will be obsolete

        // 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("DataType"); }

        // Creates a copy of an existing DataType using its id
        DataType( const hid_t type_id );

        // Default constructor
        DataType();

        // Destructor: properly terminates access to this datatype.
        virtual ~DataType();
   private:
        void p_commit(hid_t loc_id, const char* name);
};
#ifndef H5_NO_NAMESPACE
}
#endif
#endif

---