Wraps a numeric matrix of i.i.d. samples as a gmm_target. The resulting
target carries no log_density, so it can only feed regimes "moment"
(via empirical moments) and "sample" (classical EM).
Value
A gmm_target object.
See also
Other targets:
banana_target(),
donut_target(),
epanechnikov_target(),
maxent_target(),
mixture_target()