Version 3.0, pre-release 1

This is the first pre-release of das3 stream parsing code. It has been used internally on a daily basis since Feb. 15th 2024. This version provides:

• Support for das-basic-stream-v3.0 with continued support for legacy v2 streams.
• Support for named vector frames in streams and geometric vectors as a data type.
• A new utility program, das3_cdf for automatic conversion of streams to CDF files.
• XML schema files defining the formats understood by the stream parser.

The entire test-suite from das v2 was retained. All development was tested against legacy streams on each build.

das v3 streams are much richer than the v2 format and provide for:

• Many more data types, including:
  • Signed and unsigned integers of 1,2,4 & 8 bytes
  • Geometric Vectors of real values and integers
  • Non-numeric strings as data to support events lists
  • Blobs for embedding other data types within an overall stream wrapper
• Up to rank 8 datasets
• Multi-language internationalization support for object properties
• Vector frame definitions to assist with automatic coordinate transformations
• A pure XML document type without packet tags
• Coordinate axis hints including polar, cylindrical, spherical and the video time axis.

This is a pre-release. The following features are not yet supported, but are due to be finished on the road to release:

• das3_text a binary to UTF-8 stream or UTF-8 document converter
• das3_bin bin-average data in 1-N named coordinate dimensions, outputs avg, min, max and stddev.
• das3_psd An upgrade to the existing power spectral density calculator
• Reading for namespace aware streams and pure document streams without packet tags
• API functions for converting catalog definitions to query URLs

Version 2.3

This is the last of the 2.X series. Next version target is 3.0 which adds parsing for das-basic-stream-v3.0.

Updates for this version are:

• Added xmake.lua for building via xmake
• New federated catalog fetch utility: das_node
• Updated federated catalog root URLs to https everywhere
• Proper UTC time string handling when LOCALE uses a , for the radix
• Bug fix for null units strings
• Optional make setting SPICE=yes enabled for Windows
• Revised conda-build rules, including pthreads4w
• New makefile for MacOS on apple silicon
• Additional dataset loading examples
• Builds/Tests with LLVM as well as GCC and Visual Studio
• Reuse openssl file-descriptors instead of allocating new ones
• General root directory cleanup

Since SHA-Hashes pointing to this version can not be committed to the same revision that is tagged, one version after this one will contain proper download verification hashes.

Version 2.3, pre-release 4

Mostly corrects power spectral density (PSD) calculations for Rank 1 streams.
See the das2_psd wiki article for an example of the new adaptive frequency output for amplitude vs time streams.
Other updates:

• Y-axis relabeling for PSDs of down-mixed waveforms (common with high-frequency spectrum analyzers)
• Added leap-second test code
• Documentation upgrade to doyxgen 1.8.17
• Using strncpy to address more compiler warnings
• Added netbeans project file

If you are transforming streams from time domain to frequency domain, this update is recommended.

CentOS 7 RPMs are provided below. Post an Issue to request packages for other environments.

Version 2.3, pre-release 3

Further expands leap second handling and TT2000 support.

• Direct conversion of TT2000 times to µs2000, Unix Time, MJ1958 and others without slow using slow das_time conversions.
• Tested leap second handling and runtime updates via the CDF_LEAPSECONDSTABLE environment variable.
• TT2000 conversion functions are now multi-thread safe.
• SI prefix manipulation bugs fixed for ad-hoc units. ex: units of "cats" are no longer confused as "centi ats"

Note that UTC leap-second times of 23:59:60 are converted to non-leapsecond aware scales as 23:59:59.

Version 2.3, pre-release 2

Includes TT2000 support and sub-setting arbitrary variables (DasVar) no matter their backend storage mechanism.
This is the version used by SPEDAS and das2dlm as of Nov. 1st 2020.

Version 2.3, pre-release 1

This version supports das2 stream format 2.2.2, as well as full node navigation for the federated das2 catalog.
Support for the full das2.3 Interface Control Document is in progress.