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diff --git a/doc/html/Tutor/crtgrpd.html b/doc/html/Tutor/crtgrpd.html new file mode 100644 index 0000000..e92a101 --- /dev/null +++ b/doc/html/Tutor/crtgrpd.html @@ -0,0 +1,191 @@ +<HTML><HEAD> +<TITLE>HDF5 Tutorial - Creating Datasets in Groups +</TITLE> +</HEAD> + +<body bgcolor="#ffffff"> + +<!-- BEGIN MAIN BODY --> + +<A HREF="http://www.ncsa.uiuc.edu/"><img border=0 +src="http://www.ncsa.uiuc.edu/Images/NCSAhome/footerlogo.gif" +width=78 height=27 alt="NCSA"><P></A> + + [ <A HREF="title.html"><I>HDF5 Tutorial Top</I></A> ] +<H1> +<BIG><BIG><BIG><FONT COLOR="#c101cd">Creating Datasets in Groups</FONT> +</BIG></BIG></BIG></H1> + +<hr noshade size=1> + +<BODY> +<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> + </UL> +</UL> +<HR> +<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 H5Dcreate creates a +dataset at the location specified by a location identifier and a name. Similar to +H5Gcreate, 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 +refers 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> +[ <A HREF="examples/h5_crtgrpd.c">Download h5_crtgrpd.c</A> ] +<PRE> + ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + +#include <hdf5.h> +#define FILE "groups.h5" + +main() { + + hid_t file_id, group_id, dataset_id, dataspace_id; /* identifiers */ + hsize_t dims[2]; + herr_t status; + int i, j, dset1_data[3][3], dset2_data[2][10]; + + /* Initialize the first dataset. */ + for (i = 0; i < 3; i++) + for (j = 0; j < 3; j++) + dset1_data[i][j] = j + 1; + + /* Initialize the second dataset. */ + for (i = 0; i < 2; i++) + for (j = 0; j < 10; j++) + dset2_data[i][j] = j + 1; + + /* Open an existing file. */ + file_id = H5Fopen(FILE, H5F_ACC_RDWR, H5P_DEFAULT); + + /* Create the data space for the first dataset. */ + dims[0] = 3; + dims[1] = 3; + dataspace_id = H5Screate_simple(2, dims, NULL); + + /* Create a dataset in group "MyGroup". */ + dataset_id = H5Dcreate(file_id, "/MyGroup/dset1", H5T_STD_I32BE, dataspace_id +, + H5P_DEFAULT); + + /* Write the first dataset. */ + status = H5Dwrite(dataset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, + dset1_data); + + /* Close the data space for the first dataset. */ + status = H5Sclose(dataspace_id); + + /* Close the first dataset. */ + status = H5Dclose(dataset_id); + + /* Open an existing group of the specified file. */ + group_id = H5Gopen(file_id, "/MyGroup/Group_A"); + + /* Create the data space for the second dataset. */ + dims[0] = 2; + dims[1] = 10; + dataspace_id = H5Screate_simple(2, dims, NULL); + + /* Create the second dataset in group "Group_A". */ + dataset_id = H5Dcreate(group_id, "dset2", H5T_STD_I32BE, dataspace_id, H5P_DEFAULT); + + /* Write the second dataset. */ + status = H5Dwrite(dataset_id, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, + dset2_data); + + /* Close the data space for the second dataset. */ + status = H5Sclose(dataspace_id); + + /* Close the second dataset */ + status = H5Dclose(dataset_id); + + /* Close the group. */ + status = H5Gclose(group_id); + + /* Close the file. */ + status = H5Fclose(file_id); +} ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ +</PRE> + + +<A NAME="fc"> +<H3><U>File Contents</U></H3> +<P> +<B>Fig. 10.1</B> <I>The Contents of 'groups.h5'</I> +<PRE> +<IMG src="img005.gif"></PRE> +<!-- <IMG src="groups2.jpg" width="324" height="433"></PRE> --> + +</PRE> + <B>Fig. 10.2</B> <I>'groups.h5' 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> + + +<!-- BEGIN FOOTER INFO --> + +<P><hr noshade size=1> +<font face="arial,helvetica" size="-1"> + <a href="http://www.ncsa.uiuc.edu/"><img border=0 + src="http://www.ncsa.uiuc.edu/Images/NCSAhome/footerlogo.gif" + width=78 height=27 alt="NCSA"><br>The National Center for Supercomputing Applications</A><br> + <a href="http://www.uiuc.edu/">University of Illinois at Urbana-Champaign</a><br> +<!-- <A HREF="helpdesk.mail.html"> --> +<BR><A HREF="mailto:hdfhelp@ncsa.uiuc.edu"> +hdfhelp@ncsa.uiuc.edu</A> +<BR> <H6>Last Modified: August 27, 1999</H6><BR> +<!-- modified by Barbara Jones - bljones@ncsa.uiuc.edu --> +</FONT> +<BR> +<!-- <A HREF="mailto:hdfhelp@ncsa.uiuc.edu"> --> + +</BODY> +</HTML> + + + |