getCovariate Extract Covariate from an Object
 Description
This function is generic; method functions can be written to handle specific classes of objects. Classes which already have methods for this function include corStruct, corSpatial, data.frame, and varFunc. 
Usage
getCovariate(object, form, data)
Arguments
| object | any object with a  | 
| form | an optional one-sided formula specifying the covariate(s) to be extracted. Defaults to  | 
| data | a data frame in which to evaluate the variables defined in  | 
Value
will depend on the method function used; see the appropriate documentation.
Author(s)
José Pinheiro and Douglas Bates [email protected]
References
Pinheiro, J.C., and Bates, D.M. (2000) "Mixed-Effects Models in S and S-PLUS", Springer, esp. p. 100.
See Also
getCovariate.corStruct, getCovariate.data.frame, getCovariate.varFunc, getCovariateFormula 
Examples
## see the method function documentation
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Licensed under the GNU General Public License.