Definition of a State

States control the tracking to some extent and also the TPSA calculation.

 TYPE INTERNAL_STATE
     INTEGER TOTALPATH
     LOGICAL(LP) TIME,RADIATION,NOCAVITY,FRINGE,EXACTMIS,STOCHASTIC,ENVELOPE
     LOGICAL(LP) PARA_IN,ONLY_4D,DELTA
     LOGICAL(LP) SPIN,MODULATION   
 END TYPE INTERNAL_STATE

Only the logical PARA_IN is not associated to a state. It is activated by a unary plus on a state, for example,

 CALL TRACK(R, X, I1, I2, +STATE)

This unary + activates parameter dependence in PTC. Parameters are magnet properties ($b_n$ for example), which have been declared as TPSA parameters.