Rational expression in a rootlocus plot
|Objects||RationalExpression Default Values|
RationalExpression is the internal name of the expression whose roots are depicted by plot::Rootlocus.
A rootlocus plot depicts the roots of a rational function p(z, u) in the complex plane, depending on a parameter u. The expression p(z, u) is stored as the attribute RationalExpression in the rootlocus object.
Usually, a user will have no need to access the attribute RationalExpression, since it is set by plot::Rootlocus directly.
We define a rootlocus plot:
r:= plot::Rootlocus(z^2 - 2*u*z + 0.81, u = -1..1): plot(r)
The function z2 - 2 u z + 0.81 is stored as the attribute r::RationalExpression in the object r:
We can redefine this attribute:
r::RationalExpression:= z^3 - 2*u*z + 0.81: plot(r)