ConstrainedLinReg-class
                        S4 class for constrained linear regression
                        models
addInteractionToVars    Add interactions of a specific order to a
                        vector of variables
addPowToVars            Add exponent to a vector of variables
constrSelEst            Model selection algorithm for constrained
                        estimation
createFormula           Create a formula with interactions and
                        polynomials up to a desired order
createFormulaInternal   Create formula with interactions and
                        polynomials if all checks in 'createFormula'
                        have passed
extractVarname          Extract variable name from polynomial
                        expression
getBestModel            Get Best Model after Models Selection
getBetaMatrix           Extract beta matrix from 'ConstrainedLinReg'
                        model
handleMissingData       Exclude rows with missing values
makeInteractions        Add all interactions up to a desired order
makePoly                Create polynomial of degree 'maxExponent' from
                        variable names
plotModelFit            Plot errors of all models
plotModels              Plot model errors with errorbars
predict,ConstrainedLinReg-method
                        Compute predictions from constraint estimation
                        model
prepColorVec            Prepare colour vector
prepDatForPredict       Exclude rows with missing data on predictor
                        variables
prepModelNames          Extract model names from model objects
prepPlotData            Prepare data to plot model fit
print.ConstrainedLinReg
                        Print constraint estimation model
show,ConstrainedLinReg-method
                        Print constraint estimation model
sortAndPaste            Sort a vector and collapse elements together
                        using ":"
tryAsFormula            Turn character vector into formula, return
                        error if not possible
