Why MotionView UserSubroutine "sysfnc" returns all 0?

Hello everyone,

I used a SYSFNC Subroutine in my Python subroutine script, for reading some system state values. The usage are showed below:

`USER({m_mp_dth.idstring},{m_mw_dth.idstring})`

def CNFSUB(id, time, par, npar, loci, ni, locj, nj, gap, gapdot, gapdotdot, dflag, iflag):   
ipar = [0]*3    
ipar[0] = int(par[0])    
ipar[1] = int(par[1])    
ipar[2] = int(par[1])    
[dw, err] = py_sysfnc("DY", ipar)  # mP_dth, mW_dth, mW_dth [70000094, 70000093, 70000093]    
py_errmes(err, "Error calling SYSFNC for DY, dw", id, "STOP")    
print("DY -- dw=%r, err=%r" % (dw, err))
…
return …

I made a print for debugging, and all the print is:

DY -- dw=0.0, err=0

Seems the sysfnc returns 0 correctly. But i also made a output for the same system state:

DY({m_mp_dth.idstring},{m_mw_dth.idstring},{m_mw_dth.idstring})

The output curve in HyperGraph do has a value, shows below:

Why did SYSFNC not read those data? Is the problem in my scripting or defining the input parameters for USER()?

Could anyone help me out on this?

Sincere gratitude,

Garand