[R] update don't find an object

[Ronaldo Reis Junior]

Hi,

I have a situation here.

I try this update:

mmaa <- update(mma,biomass~qvartemp)

but I have this message:

Error in eval(expr, envir, enclos) : object "qvartemp" not found

but this object exist:

[1] "cont"      "i"         "levelsord" "mma"       "qvar"      "qvarmma"  
[7] "qvartemp"  "test"      "yvar"     

but if I use the glm directly it work:

mmaa <- glm(biomass~qvartemp)
Call:
glm(formula = biomass ~ qvartemp)

Deviance Residuals: 
    Min       1Q   Median       3Q      Max  
-99.500  -57.521    6.125   40.688  221.750  

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept)   509.25      21.73  23.434   <2e-16 ***
qvartempn50    60.08      37.64   1.596   0.1225    
qvartempr5    101.25      37.64   2.690   0.0123 *  
qvartempr10   101.42      37.64   2.694   0.0122 * 
....

I need to use update because other informations like family, weigths, etc

Anybody have any idea about this problem in update?

Thanks
Ronaldo
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