  This paper presents an algorithm for estimating the weight of a maximum
weighted matching by augmenting any estimation routine for the size of an
unweighted matching. The algorithm is implementable in any streaming model
including dynamic graph streams. We also give the first constant estimation for
the maximum matching size in a dynamic graph stream for planar graphs (or any
graph with bounded arboricity) using $\tilde{O}(n^{4/5})$ space which also
extends to weighted matching. Using previous results by Kapralov, Khanna, and
Sudan (2014) we obtain a $\mathrm{polylog}(n)$ approximation for general graphs
using $\mathrm{polylog}(n)$ space in random order streams, respectively. In
addition, we give a space lower bound of $\Omega(n^{1-\varepsilon})$ for any
randomized algorithm estimating the size of a maximum matching up to a
$1+O(\varepsilon)$ factor for adversarial streams.
