hdfh

Gateway to HDF H interface

Syntax

[out1,...,outN] = hdfh(funcstr,input1,...,inputN)

Description

hdfh is the MATLAB^® gateway to the HDF H interface.

[out1,...,outN] = hdfh(funcstr,input1,...,inputN) returns one or more outputs corresponding to the H function in the HDF library specified by functstr.

There is a one-to-one correspondence between H functions in the HDF library and valid values for funcstr. For example, hdfh('close',file_id) corresponds to the C library call Hclose(file_id).

Functions

Value of `funcstr`	Function Syntax	Description
`'appendable'`	`status = hdfh('appendable',access_id)`	Specifies that the element can be appended to.
`'close'`	`status = hdfh('close',file_id)`	Closes the access path to the file.
`'deldd'`	`status = hdfh('deldd',file_id,tag,ref)`	Deletes a tag and reference number from the data descriptor list.
`'dupdd'`	`status = hdfh('dupdd',file_id,tag,ref,old_tag,old_ref)`
`'endaccess'`	`status = hdfh('endaccess',access_id)`	Terminates access to a data object by disposing of the access identifier.
`'fidinquire'`	`[filename,access_mode,attach,status] = hdfh('fidinquire',file_id)`	Returns information about specified file.
`'find'`	`[tag,ref,offset,length,status] = hdfh('find',file_id,... search_tag,search_ref,search_type,dir)`	Locates the next object to be searched for in an HDF file. `search_type` can be `'new'` or `'continue'`. The `dir` input can be `'forward'` or `'backward'`.
`'getelement'`	`[data,status] = hdfh('getelement',file_id,tag,ref)`	Reads the data element for the specified tag and reference number.
`'getfileversion'`	`[major,minor,release,info,status] = hdfh('getfileversion',file_id)`	Returns version information for an HDF file.
`'getlibversion'`	`[major,minor,release,info,status] = hdfh('getlibversion')`	Returns version information for the current HDF library.
`'inquire'`	`[file_id,tag,ref,length,offset,position,access,... special,status] = hdfh('inquire',access_id)`	Returns access information about a data element.
`'ishdf'`	`tf = hdfh('ishdf',filename)`	Determines if a file is an HDF file.
`'length'`	`length = hdfh('length',file_id,tag,ref)`	Returns the length of a data object specified by the tag and reference number.
`'newref'`	`ref = hdfh('newref',file_id)`	Returns a reference number that can be used with any tag to product a unique tag/reference number pair.
`'nextread'`	`status = hdfh('nextread',access_id,tag,ref,origin)`	Searches for the next data descriptor that matches the specified tag and reference number. `origin` can be `'start'` or `'current'`.
`'number'`	`num = hdfh('number',file_id,tag)`	Returns the number of instances of a tag in a file.
`'offset'`	`offset = hdfh('offset',file_id,tag,ref)`	Returns the offset of a data element in the file.
`'open'`	`file_id = hdfh('open',filename,access,n_dds)`	Provides an access path to an HDF file by reading all the data descriptor blocks into memory.
`'putelement'`	`count = hdfh('putelement',file_id,tag,ref,X)`	Writes a data element or replaces an existing data element in an HDF file. `X` must be a `uint8` array.
`'read'`	`X = hdfh('read',access_id,length)`	Reads the next segment in a data element.
`'seek'`	`status = hdfh('seek',access_id,offset,origin)`	Sets the access pointer to an offset within a data element. `origin` can be `'start'` or `'current'`.
`'startread'`	`access_id = hdfh('startread',file_id,tag,ref)`
`'startwrite'`	`access_id = hdfh('startwrite',file_id,tag,ref,length)`
`'sync'`	`status = hdfh('sync',file_id)`
`'trunc'`	`length = hdfh('trunc',access_id,trunc_len)`	Truncates the specified data object to the given length.
`'write'`	`count = hdfh('write',access_id,X)`	Writes the next data segment to a specified data element. `X` must be a `uint8` array.

Output Arguments

A status or identifier output of -1 indicates that the operation failed.

Limitations

hdfh does not support these functions in the NCSA H interface:
- Hcache
- Hendbitaccess
- Hexist
- Hflushdd
- Hgetbit
- Hputbit
- Hsetlength
- Hshutdown
- Htagnewref

Version History

Introduced before R2006a