I   Body code for the center of motion of the body. 
   frame      I   The reference frame of the states. 
   first      I   First valid time for which states can be computed. 
   last       I   Last valid time for which states can be computed. 
   segid      I   Segment identifier. 
   intlen     I   Length of time covered by logical record. 
   n          I   Number of coefficient sets. 
   polydg     I   Chebyshev polynomial degree. 
   cdata      I   Array of Chebyshev coefficients. 
   btime      I   B