Start writing the post about asdf

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content/post/asdf.md

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+---
+author: vadim
+date: 2018-11-10
+title: "Advanced Scientific Data Format"
+image: /post/asdf/logo.png
+description: "What is ASDF, why it is awesome, why you should and how to use it. ASDF in source{d} projects."
+categories: ["technical"]
+---
+
+[Advanced Scientific Data Format](https://github.com/spacetelescope/asdf) (ASDF)
+is a next generation serialization format for scientific data. This means that
+it focuses on storing sparse and dense tensors in an efficient way.
+ASDF project started by [Michael Droettboom](https://github.com/mdboom) (Matplotlib; astropy)
+at SpaceTelescope Institute in 2014. ASDF is not implementation-driven, it is based on
+the well-defined [standard](https://asdf-standard.readthedocs.io/en/latest/).
+However, there is only one maintained software library written in Python.
+While historically ASDF targetted astronomers, it is actually abstracted away
+from any scientific domain and is completely versatile.
+
+Why another format? Currently, the most popular scientific serialization
+format is [HDF5](https://support.hdfgroup.org/HDF5/). HDF5 was described many years
+ago and is somewhat morally outdated has problems with performance which were
+described in ["Moving away from HDF5"](https://cyrille.rossant.net/moving-away-hdf5/).
+So ASDF tries to take a fresh look on scientific data and account the typical
+modern usage patterns.
+
+## Features
+
+* Transparent, automatic, on-the-fly compression and decompression with zlib, bzip2 or lz4.
+* YAML header with binary blocks appended to the tail. All the perks of using YAML are preserved.
+* Uncompressed tensors can be [memory mapped](https://en.wikipedia.org/wiki/Memory-mapped_file) so that the operating memory consumption is very low with tiny performance penalty for sequential read and write. Killer feature if the tensors are big.
+* Data structure can be validated with YAML schemas.
+* Python and numpy arrays are first-class citizens.
+* The tags mechanism allows to extend for new binary data types easily. Though it is rarely needed in practice.
+
+## Code examples
+
+## ASDF at source{d}