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<BIG><BIG><BIG><FONT COLOR="#c101cd">Creating Datasets in Groups</FONT>
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<H2>Contents:</H2>
<UL>
<LI> <A HREF="#ds"> Creating datasets in groups</A>
<LI> Programming Example
<UL>
<LI> <A HREF="#desc">Description</A>
<!-- <LI> <A HREF="#rem">Remarks</A> -->
<LI> <A HREF="#fc">File Contents</A>
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<A NAME="ds">
<H2><U>Creating datasets in groups</U></H2>
We have shown how to create groups, datasets, and attributes.
In this section, we show how to create datasets in groups.
Recall that <code>H5Dcreate</code>/<code>h5dcreate_f</code>
creates a dataset at the location specified by a location identifier and
a name. Similar to <code>H5Gcreate</code>/<code>h5gcreate_f</code>,
the location identifier can be a
file identifier or a group identifier and the name can be
relative or absolute. The location identifier and the name together determine
the location where the dataset is to be created. If the location identifier
and name refer to a group, then the dataset is created in that group.
<H2> Programming Example</H2>
<A NAME="desc">
<H3><U>Description</U></H3>
This example shows how to create a dataset in a particular group.
It opens the file created in the previous example and creates two datasets.<BR>
<UL>
[ <A HREF="examples/h5_crtgrpd.c">C Example</A> ] - <code>h5_crtgrpd.c</code>
<BR>
[ <A HREF="examples/grpdsetexample.f90">FORTRAN Example</A> ]
- <code>grpdsetexample.f90</code><BR>
[ <A HREF="examples/java/CreateGroupDataset.java">Java Example</A> ]
- <code>CreateGroupDataset.java</code>
</UL>
<B>NOTE:</B> To download a tar file of the examples, including a Makefile,
please go to the <A HREF="references.html">References</A> page.
<A NAME="fc">
<H3><U>File Contents</U></H3>
<P>
<B>Fig. 10.1</B> <I>The Contents of <code>groups.h5</code>
(<code>groupsf.h5</code> for FORTRAN)</I>
<PRE>
<IMG src="img005.gif"></PRE>
<!-- <IMG src="groups2.jpg" width="324" height="433"></PRE> -->
</PRE>
<B>Fig. 10.2a</B> <I><code>groups.h5</code> in DDL</I>
<PRE>
HDF5 "groups.h5" {
GROUP "/" {
GROUP "MyGroup" {
GROUP "Group_A" {
DATASET "dset2" {
DATATYPE { H5T_STD_I32BE }
DATASPACE { SIMPLE ( 2, 10 ) / ( 2, 10 ) }
DATA {
1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
1, 2, 3, 4, 5, 6, 7, 8, 9, 10
}
}
}
GROUP "Group_B" {
}
DATASET "dset1" {
DATATYPE { H5T_STD_I32BE }
DATASPACE { SIMPLE ( 3, 3 ) / ( 3, 3 ) }
DATA {
1, 2, 3,
1, 2, 3,
1, 2, 3
}
}
}
}
}
</PRE>
<B>Fig. 10.2b</B> <I><code>groupsf.h5</code> in DDL</I>
<PRE>
HDF5 "groupsf.h5" {
GROUP "/" {
GROUP "MyGroup" {
GROUP "Group_A" {
DATASET "dset2" {
DATATYPE { H5T_STD_I32BE }
DATASPACE { SIMPLE ( 10, 2 ) / ( 10, 2 ) }
DATA {
1, 1,
2, 2,
3, 3,
4, 4,
5, 5,
6, 6,
7, 7,
8, 8,
9, 9,
10, 10
}
}
}
GROUP "Group_B" {
}
DATASET "dset1" {
DATATYPE { H5T_STD_I32BE }
DATASPACE { SIMPLE ( 3, 3 ) / ( 3, 3 ) }
DATA {
1, 1, 1,
2, 2, 2,
3, 3, 3
}
}
}
}
}
</PRE>
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<BR> <H6>Last Modified: June 22, 2001</H6><BR>
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