Sphere: A redis-like datastore for dataset on sphere

Introduce

Sphere is a redis-like datastore for dataset on sphere. It is an implementation of HEALPix from JPL, NASA.

Please refer the article below for details of HEALPix:

• HEALPix — a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• By K. M. Gorski et. al.
• http://arxiv.org/abs/astro-ph/0409513

The project is just at the beginning, and is not ready for use.

Command-line commands

• sph cli
• sph init
• sph start
• sph stop
• sph part

Data types inside Sphere

We list all accepable types as below:

• KIND: i.e. pure data, height-based data, time-based data , time-height-based data

• INDEX: all indexes are 1-based

  • #DIGITS, such as #1234, #5678, for a total ring index
  • DIGITS#DIGITS, such as 123#5678, for the 5678th pixel in the 123th ring
  • @DIGITS, such as @1234, @5678, for a total nested index
  • DIGIT@DIGIT@DIGIT..., such as 3@1@2@3@4, for a nested tree path
  • DIGITS@DIGITS, such as 3@1234, 678@5678, for a nested index inside a particular part

• ANGULAR: a angular in radius or degree form

  • FLOAT, such as 123.45, for radius-based angular
  • DIGITS:DIGITS:DIGITS such as 359:59:59, for degree-based angular

• COORD: lng-lat coordinate on sphere

  • ANGULAR ANGULAR

• KEY: a string

• HEIGHT: a number

• TIME:

• VALUE:

Client commands

Index query

• all
• ring INDEX
• rindex INDEX
• nindex INDEX
• pindex INDEX
• path INDEX
• coord INDEX

Data type query

• kind KEY
• type KEY

Basic

• get COORD KEY
• set COORD KEY VALUE

Height-based data

• zget HEIGHT COORD KEY
• zset HEIGHT COORD KEY VALUE

Time-based data

• tget TIME COORD KEY
• tset TIME COORD KEY VALUE

Time-Height-based data

• tzget TIME HEIGHT COORD KEY
• tzset TIME HEIGHT COORD KEY VALUE

Field operator

• grad KEY1 KEY2

• zgrad HEIGHT KEY1 KEY2

• tgrad TIME KEY1 KEY2

• tzgrad TIME HEIGHT KEY1 KEY2

• rot KEY1 KEY2

• zrot HEIGHT KEY1 KEY2

• trot TIME KEY1 KEY2

• tzrot TIME HEIGHT KEY1 KEY2

• div KEY1 KEY2

• zdiv HEIGHT KEY1 KEY2

• tdiv TIME KEY1 KEY2

• tzdiv TIME HEIGHT KEY1 KEY2