if error_bars then 
  if (ytype.eq."AMP") then 
    define real a3[&1] 
                                ! RL: pourquoi ce facteur 2 ??? 
                                !    LET A3 1|SQRT(2*RG[&2]*1E6+1E-34)	! Weight is for amplitude 
    let a3 1|sqrt(rg[&2]*1e6+1e-34)             ! Weight is for amplitude 
    err y uv[1] uv[2] a3 
  else if (ytype.eq."REAL".or.ytype.eq."IMAG") then 
    define real a3[&1] 
    let a3 1|sqrt(rg[&2]*1e6+1e-34)             ! 
    err y uv[1] uv[2] a3 
  endif 
endif