Data from an ncWMS server visualized using GIS desktop software
ncWMS is an Open Source implementation of the Open Geospatial Consortium's Web Map Service (WMS) specification for multidimensional gridded environmental data. ncWMS can read data in a large number of common scientific data formats — notably the NetCDF format with the Climate and Forecast (CF) conventions — and efficiently generate map imagery in thousands of different coordinate reference systems.
Version 4.3.1 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
Version 4.3.0 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
In part 1, we explained what data chunking is about in the context of scientific data access libraries such as netCDF-4 and HDF5, presented a 38 GB 3-dimensional dataset as a motivating example, discussed benefits of chunking, and showed with some benchmarks what a huge difference chunk shapes can make in balancing read times for data that will be accessed in multiple ways.
In this post, I'll continue looking at that example dataset to see how we can derive good chunk shapes, generalize to other datasets, look at how long it can take to rechunk a multidimensional dataset, and look at the use of Solid State Disk (SSD) for both accessing and rechunking data.
Version 4.2.6 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
The Open Geospatial Consortium membership has adopted the Climate and Forecast (CF) extension to the existing OGC Network Common Data Form (NetCDF) Core Encoding Standard version 1.0. All of the OGC's netCDF standards documents are available for free download from the OGC network Common Data Forum (netCDF) standards suite page.
What is data chunking? How can chunking help to organize large multidimensional datasets for both fast and flexible data access? How should chunk shapes and sizes be chosen? Can software such as netCDF-4 or HDF5 provide better defaults for chunking? If you're interested in those questions and some of the issues they raise, read on ...
Version 4.2.5 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
Version 4.2.4 of the netCDF Operators (NCO) has been released. NCO is an Open Source package that consists of a dozen standalone, command-line programs that take netCDF files as input, then operate (e.g., derive new data, average, print, hyperslab, manipulate metadata) and output the results to screen or files in text, binary, or netCDF formats.
