1HDF(1) General Commands Manual HDF(1)
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6 hdf - Hierarchical Data Format library
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9 -lmfhdf -ldf -ljpeg -lz
10 {HDFLIBDIR}/libmfhdf.a {HDFLIBDIR}/libdf.a {HDFLIBDIR}/libjpeg.a
11 {HDFLIBDIR}/libz.a
12
15 HDF is a multi-object file format that facilitates the transfer of var‐
16 ious types of scientific data between machines and operating systems.
17 Machines currently supported include the Cray, HP, Vax, Sun, IBM
18 RS/6000, Silicon Graphics, Macintosh, and IBM PC computers. HDF allows
19 self-definitions of data content and easy extensibility for future
20 enhancements or compatibility with other standard formats. HDF includes
21 Fortran and C calling interfaces,and utilities to prepare raw image of
22 data files or for use with other NCSA software. The HDF library con‐
23 tains interfaces for storing and retrieving compressed or uncompressed
24 8-bit and 24-bit raster images with palettes, n-Dimensional scientific
25 datasets and binary tables. An interface is also included that allows
26 arbitray grouping of other HDF objects.
27 HDF Raster Images
30 HDF supports the storing of both 8-bit and 24-bit raster images. As
31 well as storing information about the dimensions and palette of a
32 raster image, HDF supports raster image compression. In previous ver‐
33 sions of HDF, Run-length encoding and Imcomp compression were both sup‐
34 ported. With HDF> 3.3 JPEG compression is also available.
35 HDF Scientific Data Sets
38 Scientific Data Sets (SDSs) are useful for storing n-Dimensional grid‐
39 ded data. The actual data in the dataset can be of any of the "stan‐
40 dard" number types: 8, 16 and 32bit signed and unsigned integers and 32
41 and 64bit floating point values. In addition, a certain amount of
42 meta-data can be stored with an SDS including:
43 o The coordinate system to use when interpreting or displaying the data.
45 o Scales to be used for each dimension.
46 o Labels for each dimension and the dataset as a whole.
47 o Units for each dimension and the data.
48 o The valid max and min values for the data.
49 o Calibration information for the data.
50 o Fill or missing value information.
51 o Ability of have more than one file open at a time.
52 o A more general framework for meta-data within the SDS data-model
53 (allowing 'name = value' styel meta-data).
54 o Support for an "unlimited dimension" in the SDS data-model, making
55 it possible to append planes to an array along one dimension.
56 HDF Annotations
58 Any object in an HDF file can have annotations associated with it.
59 There are a number of types of annotations:
60 o Labels are assumed to be short strings giving the "name" of a
62 data object.
63 o Descriptions are longer text segments that are useful for giving
64 more indepth information about a data object
65 o File annotations are assumed to apply to all of the objects in a
66 single file.
67 HDF Vset Interfaces
69 The Vset module provides interfaces to two basic HDF building blocks.
70 Vgroups are generic grouping elements allowing a user to associate
71 related objects within an HDF file. As Vgroups can contain other
72 Vgroups, it is possible to build a hierarchical file. Vdatas are data
73 structures made up of fields and records. Data is organized into
74 'fields' within each Vdata. Each field is identified by a unique
75 'fieldname'. The type of each field may be any of the basic number
76 types that HDF supports. Fields of different types may exist within
77 the same Vdata.
78 By combining Vdatas in Vgroups it is possible to represent higher level
80 data constructs: mesh data, multi-variate datasets, sparse matrices,
81 finite-element data, spreadsheets, splines, non-Cartesian coordinate
82 data, etc.
83 HDF > 3.3 and netCDF
86 HDF > 3.3 merges in the netCDF library produced by Unidata. The full
87 netCDF library is supported as is a new "multi-file" SDS interface.
88 Both of these interfaces can read old netCDF files and HDF files trans‐
89 parently.
90 EXAMPLES
94 All HDF routines require the header "hdf.h" to be included in the C
95 source file. If using the SDS routines the header "mfhdf.h" should be
96 included instead in in the C source file. Fortran programs should use
97 "dffunc.inc" and "hdf.inc".
98 To compile a program that makes HDF calls on most Unix platforms.
100 HDFLIBDIR = /usr/local/lib/hdf
102 HDFINC = /usr/local/include/hdf
103 (FORTRAN):
105 f77 myprog.f -I{HDFINC} -o myprog {HDFLIBDIR}/libmfhdf.a \
106 {HDFLIBDIR}/libdf.a {HDFLIBDIR}/libjpeg.a {HDFLIBDIR}/libz.a
107 (C):
109 cc myprog.c -I{HDFINC} -o myprog {HDFLIBDIR}/libmfhdf.a \
110 {HDFLIBDIR}/libdf.a {HDFLIBDIR}/libjpeg.a {HDFLIBDIR}/libz.a
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115 The HDF WWW page is located at http://hdf.ncsa.uiuc.edu/
116 For the vast majority of users, the "Users Guide" documents and the
118 "Reference" manuals should be sufficient.
119 You may download the documentation via ftp on NCSA's anonymous ftp
121 server. (ftp.ncsa.uiuc.edu:/HDF). On anonymous ftp there the documenta‐
122 tion is available in Postscript, PDF and MIF.
123
127 NCSA Software Development Division
128 Hierarchical Data Format Group
129 152 Computing Applications Bldg.
130 605 E. Springfield Ave.
131 Champaign, IL 61820
132
135 4.1
136
138 UNIVERSITY OF ILLINOIS (UI), NATIONAL CENTER FOR SUPERCOMPUTING APPLI‐
139 CATIONS (NCSA), Software Distribution Policy for Public Domain Software
140 NCSA HDF Version 4.1 source code and documentation are in the public
142 domain, available without fee for education, research, non-commercial
143 and commercial purposes. Users may distribute the binary or source
144 code to third parties provided that this statement appears on all
145 copies and that no charge is made for such copies.
146 UI MAKES NO REPRESENTATIONS ABOUT THE SUITABILITY OF THE SOFTWARE FOR
148 ANY PURPOSE. IT IS PROVIDED "AS IS" WITHOUT EXPRESS OR IMPLIED WAR‐
149 RANTY. THE UI SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY THE USER
150 OF THIS SOFTWARE. The software may have been developed under agree‐
151 ments between the UI and the Federal Government which entitle the Gov‐
152 ernment to certain rights.
153 We ask, but do not require that the following message be include in all
155 derived works:
156 Portions developed at the National Center for Supercomputing
158 Applications at the University of Illinois at Urbana-Champaign.
159 By copying this program, you, the user, agree to abide by the condi‐
161 tions and understandings with respect to any software which is marked
162 with a public domain notice.
163 Acknowledgements: ----------------
165 Portions of this software were developed by the Unidata Program at the
167 University Corporation for Atmospheric Research, specifically the
168 NETCDF distribution used.
169 This product also includes software developed by the Independent JPEG
171 Group, specifically the IJPEG library libjpeg.a.
172 This product also includes software developed by Jean-loup Gailly and
174 Mark Adler , specifically the ZLIB library libz.a.
175 This product includes software developed by the University of Califor‐
177 nia, Berkeley and its contributors.
178
181 NCSA Software Deveopment Division
182 Hierarchical Data Format Group
183 email: hdfhelp@ncsa.uiuc.edu
184
187 /usr/local/lib/hdf/{libmfhdf.a,libdf.a,libjpeg.a,libz.a}
188 hdf libraries
189 /usr/local/bin Location of most hdf utilities
190 /usr/local/include/hdf Location of include file hdf.h and others
191
194 hdfls(1), hdfpack(1), hdfunpac(1), hdp(1)
195NCSA HDF 4.1 July 1996 HDF(1)