Create a Gamma element in which both the k and theta parameters are elements.
Create a Gamma element in which the k parameter is an element and theta is a constant.
Create a Gamma element in which the k parameter is an element and theta is a constant. Theta defaults to 1.
Create a Gamma element in which both k and theta parameters are constants.
Create a Gamma element in which both k and theta parameters are constants. Theta defaults to 1.
Create an element of this type with the given arguments.