(swsym-operator)=

# swsym.operator

## Syntax
  
`[symOp, symInfo] = swsym.operator(sym)`
  
`[symOp, symInfo] = swsym.operator(sym,fid)`
 
## Description
  
`[symOp, symInfo] = swsym.operator(sym)` generates *all* symmetry
elements from a given set of generators. It also accepts space group
labels or space group index or string of symmetry operators.
  
## Input Arguments
  
`sym`
: Line index in the `symmetry.dat` file or string of the
  symmetry operators or matrix of symmetry generators with dimensions of
  $[3\times 4\times n_{op}]$. For example: `sym = 'P n m a'`.
  
`fid`
: If non-zero, the symmetry operators will be printed to the file
  identified by `fid`, the following values are valid:
  * `0`   no printed output (default),
  * `1`   standard output (Command Line),
  * `fid` text file opened before using `fid = fopen(path)`.
  
## Output Arguments
  
`symOp`
: All the symmetry elements in a matrix with dimensions of $[3\times
  4\times n_{op}]$.
 
`symInfo`
: Structure that contains additional information about the space 
  group with the following fields:
  * `name`    Name of the space group, if the `swsym.generator`
              function is called with no input, name stores the name of
              all space groups from `symmetry.dat` file in a cell.
  * `str`     The string of the symmetry operations.
  * `num`     The line index in the `symmetry.dat` file.
  
## See Also
  
[swsym.generator](#swsym-generator)