Text formats are input and output file formats used by load_text and save_text functions in snapshot class.

They are ASCII files containing textual representation of double precision floating point numbers.
All quantities are double precision point numbers except for nsys, nbod, id and state, which are integers.
State is defined in the ensemble:
  - 0 means active
  - 1 is disabled
  - other values are intermediate inactive states.

Text file format:

<number of systems> <number of bodies> <number of system attributes> <number of body attributes>


<system unique id> <system time> <system state>
<system attribute> <system attribute> ...
     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...

     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...

     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...


<system unique id> <system time> <system state>
<system attribute> <system attribute> ...
     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...

     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...

     <mass of the body> 
     <x> <y> <z>
     <velocity x> <velocity y> <velocity z>
         <body attribute> <body attribute> ...


  .
  .
  .

The example above is for 3-body systems.

Explanation:

Header:
 - \<number of systems\>: Number of systems contained in this file. There should be exact number of blocks describing
 the properties of the system and bodies in the system after the header.
 - \<number of bodies\>: Number of bodies per system. All systems have equal number of bodies
 - \<number of system attributes\>: Number of general-purpose attributes per system. The purpose of the attributes is
 determined by the application
 - \<number of body attributes\> : Number of general-purpose attributes per body. The purpose of the attributes is
 determined by the application

 System Block:
  - \<system unique id\>: Unique identifier for the system. The systems may be reduced or removed. The order of the systems
  may also change. This unique identifier is used to match systems between input/output files.
  - \<system time\> : Physical time of the system.
  - \<system state\> : Integration state of the system: 0 means active, 1 is disabled, other values are intermediate 
  inactive states that may be reactivated.
  - \<system attribute\>: A general-purpose attribute of the system. There are a specific number of these attributes and the order is important.

 Body Block:
 - \<mass of the body\>: Mass of the body 
 - \<x\> \<y\> \<z\>: Three components of the position of the body
 - \<velocity x\> <velocity y\> \<velocity z\>: Three components of the velocity of the body
 - \<body attribute\>: a general-purpose attribute of the body, repeated on the same line and the order must be 
 preserved.