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John Readey, The HDF Group   We’ve recently announced a new viewer application for HDF5 files: HDF Compass. In this blog post we’ll explore the motivations for providing this tool, review its features, and speculate a bit about future direction for Compass. HDF Compass is a desktop viewer application for HDF5 and other file formats. A free and open source software product, it runs on Mac OS X, Windows, and Linux.   Compass was initially developed by Andrew Collette, a Research Scientist with IMPACT (Institute for Modeling Plasma, Atmospheres and Cosmic Dust).  He has decided to work with The HDF Group to further the development of Compass. Andrew has written a very interesting blog that goes into some of the background of Compass and...

Lindsay Powers - The HDF Group The HDF Group provides free, open-source software that is widely used in government, academia and industry. The goal of The HDF Group is to ensure the sustainable development of HDF (Hierarchical Data Format) technologies and the ongoing accessibility of HDF-stored data because users and organizations have mission-critical systems and archives relying on these technologies. These users and organizations are a critical element of the HDF community and an important source of new and innovative uses of, and sustainability for, the HDF platforms, libraries and tools. We want to create a sustainability model for the open access platforms and libraries that can serve these diverse communities in the future use and preservation of their data. As a...

* With Python’s Help

Gerd Heber, The HDF Group

Before the recent release of our PyHexad Excel add-in for HDF5[1], the title might have sounded like the slogan of a global coffee and baked goods chain. That was then. Today, it is an expression of hope for the spreadsheet users who run this country and who either felt neglected by the HDF5 community or who might suffer from a medical condition known as data-bulging workbook stress disorder. In this article, I would like to give you a quick overview of the novel PyHexad therapy and invite you to get involved (after consulting with your doctor).

To access the data in HDF5 files from Excel is a frontrunner among the all-time TOP 10 most frequently asked for features. A spreadsheet tool might be a convenient window into, and user interface for, certain data stored in HDF5 files. Such a tool could help overcome Excel storage and performance limitations, and allow data to be freely “shuttled” between worksheets and HDF5 data containers. PyHexad ([4],[5],[6],[7]) is an attempt to further explore this concept.  

Elena Pourmal, The HDF Group What happened to my compression? One of the most powerful features of HDF5 is the ability to compress or otherwise modify, or “filter,” your data during I/O. By far, the most common user-defined filters are ones that perform data compression.  As you know, there are many compression options. There are filters provided by the HDF5 library (“predefined filters,”) which include several types of filters for data compression, data shuffling and checksum. Users can implement their own “user-defined filters” and employ them with the HDF5 library. [caption id="attachment_10741" align="alignright" width="300"] Cars in a 1973 Philadelphia junkyard – image from National Archives and Records Administration[/caption] While the programming model and usage of the compression filters is straightforward, it is possible for...

...we focus on how far we can push our personal computing devices with Spark. It consists of 7,850 HDF-EOS5 files covering 27 years and totals about 120 GB. We use a driver script, which reads a dataset of interest from each file in the collection, computes per-file quantities of interest, and gathers them in a CSV file for visualization. The processing time on our reference tablet machine for 3.5 years of data using 4 logical processors was about 10 seconds....