Syntax

XPCS {<PCS-statement>} END
<PCS-statement>:==
 ASSIgn <sel> <sel> <sel> <sel> <sel> <real> <real>
        ! atom i, j, k, l, m, pseudocontact shift (ppm), PCS-err
        ! i=metal, j=Z axis of the tensor, k=X of the tensor,
        ! l=Y axis of the tensor, m=shifted nucleus
 CLASsification <name>
        ! Starts a new class. The  COEFficients can be 
        ! different for each class.
 TOLL <1 | 0>
        ! Switch tolerance in FANTALIN (1=Yes, 0=No)
 COEFficient <real> <real>
        ! Magnetic suspectibility tensor parameters: A1, A2
 FORCeconstant <real>
        ! Force constant for the current class.
 NREStraints <integer>
        ! Number of slots for restraints to allocate in memory.
 PRINt THREshold <real> <ALL | class<name>>
        ! Prints violations larger than the specified value for 
        ! all restraints or for a specific class.
 RESEt
        ! Erases the restraint table, but keeps NRES.
 SAVE
        ! Filename to save PCS values.
 FMED <real> <integer>
        ! The real is the percentage of structures to use for 
        ! the averaging and the integer is the class number.
        ! Calculates average tensor parameters (when fitting 
        ! magnetic suspectibility).
        ! To reset the tensor parameters use FMED 1 0.
        ! The averaged values of the tensor parameters are 
        ! stored in $chiax and $chirh.
 ERRON
        ! Switches Monte Carlo error evaluation ON.
 ERROFF
        ! Switches Monte Carlo error evaluation OFF.
 FON    
        ! Switches tensor auto-update mode ON.
 FOFF   
        ! Switches tensor auto-update mode OFF.
 SON    
        ! Switches saving mode ON.
 SOFF   
        ! Switches saving mode OFF.
 FRUN <integer>
        ! class number is the integer.
        ! Runs FANTALIN for fitting magnetic suspectibility 
        ! parameters for the given class.