H5F_CREATE
Syntax | Return Value | Arguments | Keywords | Example | Version History | See Also
The H5F_CREATE function is the primary function for creating HDF5 files.
Note
As an alternative, see H5_CREATE.
Syntax
Result = H5F_CREATE(Filename)
Return Value
Result is a file identifier for the newly-created file; this file identifier should be closed by calling H5F_CLOSE when it is no longer needed.
Arguments
Filename
A string giving the name of the file to create.
Keywords
None
Example
; create HDF5 file file = 'hdf5_out.h5' fid = H5F_CREATE(file) ; create some data data = hanning(100,200) ; create a datatype datatype_id = H5T_IDL_CREATE(data) ; create a dataspace, allow the dataspace to be extendable dataspace_id = $ H5S_CREATE_SIMPLE([100,100],max_dimensions=[200,200]) ; create the dataset dataset_id = H5D_CREATE(fid,'Hanning',datatype_id,dataspace_id, $ chunk_dimensions=[20,20]) ; extend the size of the dataset to fit the data H5D_EXTEND,dataset_id,size(data,/dimensions) ; write the data to the dataset H5D_WRITE,dataset_id,data ; close some identifiers H5S_CLOSE,dataspace_id H5T_CLOSE,datatype_id ; create a reference attribute attached to the dataset dataspace_id = H5S_CREATE_SIMPLE(size(data,/dimensions)) ; select a 30x30 element region of interest in the dataset H5S_SELECT_HYPERSLAB,dataspace_id,[40,40],[1,1], $ block=[30,30],/reset ; create a dataspace region reference ref = H5R_CREATE(fid,'Hanning',dataspace=dataspace_id) ; create a datatype for the reference datatype_id = H5T_REFERENCE_CREATE(/region) ; create a one element dataspace for the single reference dataspace_id = H5S_CREATE_SIMPLE(1) ; make the reference an attribute of the dataset attr_id = H5A_CREATE(dataset_id,'Ref',datatype_id,dataspace_id) H5A_WRITE,attr_id,ref H5A_CLOSE,attr_id ; create a dummy attribute and delete it attr_id2 = $ H5A_CREATE(dataset_id,'Dummy',datatype_id,dataspace_id) ; attribute must be closed before it can be deleted H5A_CLOSE,attr_id2 H5A_DELETE,dataset_id,'Dummy' ; create a group to hold sample datatypes and links group_id = H5G_CREATE(fid,'Datatypes and links') ; add a comment to the group H5G_SET_COMMENT,fid,'Datatypes and links', $ 'This is a sample comment' ; add a datatype to the group datatype_id2 = H5T_IDL_CREATE(1) ; add the datatype to the group and give it a name H5T_COMMIT,group_id,'Integer',datatype_id2 ; create an array datatype and add it to the group with a name datatype_id3 = H5T_ARRAY_CREATE(datatype_id2,[3,4]) H5T_COMMIT,group_id,'Integer 2',datatype_id3 ; rename previous datatype H5G_MOVE,group_id,'Integer 2','Integer Array' ; close temporary datatypes H5T_CLOSE,datatype_id3 H5T_CLOSE,datatype_id2 ; create a compound datatype and add it to the group struct = {float:1.0, double:1.0d} datatype_id4 = $ H5T_IDL_CREATE(struct,member_names=['Float','Double']) ; create an integer datatype and insert it in the ; compound datatype datatype_id5 = H5T_IDL_CREATE(1) H5T_INSERT,datatype_id4,'Integer',datatype_id5 ; add the datatype to the group and give it a name H5T_COMMIT,group_id,'Compound',datatype_id4 ; close datatype identifiers H5T_CLOSE,datatype_id5 H5T_CLOSE,datatype_id4 ; add a hard link from the group to the Hanning dataset H5G_LINK,fid,'Hanning','Link to Hanning',new_loc_id=group_id ; add a dummy link H5G_LINK,group_id,'Integer','Link to Integer' ; remove dummy link H5G_UNLINK,group_id,'Link to Integer' ; close remaining open identifiers H5G_CLOSE,group_id H5D_CLOSE,dataset_id H5T_CLOSE,datatype_id H5S_CLOSE,dataspace_id H5F_CLOSE,fid
Version History
