code: function sqrt( x, path, sep ) {
  	var len = x.length,
  		opts = {},
  		dget,
  		dset,
  		v, i;
  	if ( arguments.length > 2 ) {
  		opts.sep = sep;
  	}
  	if ( len ) {
  		dget = deepGet( path, opts );
  		dset = deepSet( path, opts );
  		for ( i = 0; i < len; i++ ) {
  			v = dget( x[ i ] );
  			if ( typeof v === 'number' ) {
  				dset( x[i], SQRT( v ) );
  			} else {
  				dset( x[i], NaN );
  			}
  		}
  	}
  	return x;
  }
docs: SQUARE ROOT // 
  FUNCTION: sqrt( arr, path[, sep] )
  Computes an element-wise principal square root and deep sets the input array.
  
  @param {Array} arr - input array
  @param {String} path - key path used when deep getting and setting
  @param {String} [sep] - key path separator
  @returns {Array} input array