[R] error message in "sem"

[Remko Duursma]

Dear R-helpers,

i get a mysterious error message when using sem,  it reads:


"Error in tapply(grad.P[arrows.2.free], ram[ram[, 1] == 2 & ram[, 4] !=  : 
        arguments must have same length"

what does this mean?

remko



^'~,_,~'^'~,_,~'^'~,_,~'^'~,_,~'^'~,_,~'^'~,_,~'
Remko Duursma, Ph.D. student
Forest Biometrics Lab / Idaho Stable Isotope Lab
University of Idaho, Moscow, ID, U.S.A.