Showing entries tagged [zarr]

Overview of Zarr Support in netCDF-C

Beginning with netCDF version 4.8.0, the Unidata netCDF group has extended the netCDF-c library to provide access to cloud storage (e.g. Amazon S3) by providing a mapping from a subset of the full netCDF Enhanced (aka netCDF-4) data model to a variant of the Zarr data model that already has mappings to key-value pair cloud storage systems. The netCDF version of this storage format is called NCZarr.

[Read More]

Chunking Algorithms for NetCDF-C

Unidata is in the process of developing a Zarr [] based variant of netcdf. As part of this effort, it was necessary to implement some support for chunking. Specifically, the problem to be solved was that of extracting a hyperslab of data from an n-dimensional variable (array in Zarr parlance) that has been divided into chunks (in the HDF5 sense). Each chunk is stored independently in the data storage -- Amazon S3, for example.

The algorithm takes a series of R slices of the form (first,stop,stride), where R is the rank of the variable. Note that a slice of the form (first, count, stride), as used by netcdf, is equivalent because stop = first + count*stride. These slices form a hyperslab.

The goal is to compute the set of chunks that intersect the hyperslab and to then extract the relevant data from that set of chunks to produce the hyperslab.

[Read More]
Unidata Developer's Blog
A weblog about software development by Unidata developers*
Unidata Developer's Blog
A weblog about software development by Unidata developers*

Welcome

FAQs

News@Unidata blog

Take a poll!

What if we had an ongoing user poll in here?

Browse By Topic
Browse by Topic
« September 2020
SunMonTueWedThuFriSat
  
1
2
3
4
5
6
8
9
10
11
12
13
15
16
17
18
19
20
22
23
24
25
26
27
28
29
30
   
       
Today