  Every diagonalmatrix D yields an endomorphism on the n-dimensional complex
vectorspace. If one provides this space with Hoelder norms, we can compute the
operator norm of D. We define homogeneous weighted spaces as a generalization
of normed spaces. We generalize the Hoelder norms for negative values, this
leads to a proof of an extented version of the Hoelder inequality. Finally, we
formulate this version also for measurable functions.
