Compounds having either $C = C$ or $C = N$ exhibit geometrical isomerism but the other main condition for exhibiting geometrical isomerism is the presence of two different groups on double bonded carbon atoms.
Since in ketoxime, $\left( CH _{3}\right)_{2} C = NOH$, two same $\left(- CH _{3}\right)$ groups are present on double bonded carbon atom, its other form is not possible and it does not exhibit geometrical isomerism.
Compounds with $N = N$ also have two geometrical forms as
