view_hdf: Visualization and Analysis Software for HDF Files

The Clouds and the Earth's Radiant Energy System (CERES) instruments are a part of NASA's continuing commitment to long term projects that increase understanding of the Earth's climate and environment. Data products from these instruments are produced, archived and distributed by the NASA Langley Atmospheric Sciences Data Center. The CERES Data Management team has developed a visualization and analysis tool written in Interactive Data Language (IDL), view_hdf, which provides a graphical user interface for manipulating these HDF data sets. The view_hdf tool can select and subset variables from either Science Data Sets (SDS) or vdata structures in an HDF file, render both two and three dimensional graphics, and plot geolocated data onto various world map projections. Other features include multiple variable plots, difference plots, and simple statistics. Plots can be saved in PostScript, encapsulated PostScript and GIF or sent directly to a printer. Filtered subsets and statistical results can be written to a file in ASCII format for use in other analysis programs. Examples are presented which include results from the CERES instrument. Although developed mainly for the CERES project, this tool is of more general use for other data sets written in HDF. The tool was developed on a UNIX platform and has been transported to Sun, SGI, and HP workstations. It should be portable to any platform which supports IDL, the HDF libraries, and a C compiler. More information about view_hdf can be obtained at http://eosweb.larc.nasa.gov/HPDOCS/view_hdf.html.