message: added entityKey support for coarse element properties
diff: @@ -89,7 +89,16 @@ const coarse = {
  gaussian_covariance_matrix: Element.property(l => !Unit.isGaussians(l.unit) ? notCoarse('gaussians') : l.unit.coarseConformation.covariance_matrix[l.element])
  }
  -function eK(l: Element.Location) { return !Unit.isAtomic(l.unit) ? notAtomic() : l.unit.model.atomicHierarchy.entityKey[l.unit.chainIndex[l.element]]; }
  +function eK(l: Element.Location) {
  + switch (l.unit.kind) {
  + case Unit.Kind.Atomic:
  + return l.unit.model.atomicHierarchy.entityKey[l.unit.chainIndex[l.element]]
  + case Unit.Kind.Spheres:
  + return l.unit.model.coarseHierarchy.spheres.entityKey[l.element]
  + case Unit.Kind.Gaussians:
  + return l.unit.model.coarseHierarchy.gaussians.entityKey[l.element]
  + }
  +}
  const entity = {
  key: eK,
  