Off topic:Linear model error: fitted()

Question

[oars]

Hello,

I'm trying to use the fitted() function in order to retrieve the fitted (predicted) value of D2R at each value in G. I've tried the following R syntax but don't understand why I'm receiving the following error?

plot( fitted( lm.34852.g.at),
     d2r.34852[is.na(d2r.34852$D2R),"D2R"],
     xlab = "Fitted", ylab = "Observed")

 

Error in xy.coords(x, y, xlabel, ylabel, log) : 
      'x' and 'y' lengths differ

I've also tried separating the plot and fitted() portion of the code but still cannot seem to get this code to work correctly?