some more distribution test fixes
some more distribution test fixes

thirdwing/mlpack,BookChan/mlpack,theranger/mlpack,minhpqn/mlpack,palashahuja/mlpack,Azizou/mlpack,ersanliqiao/mlpack,ranjan1990/mlpack,theranger/mlpack,chenmoshushi/mlpack,darcyliu/mlpack,Azizou/mlpack,theranger/mlpack,datachand/mlpack,bmswgnp/mlpack,palashahuja/mlpack,trungda/mlpack,stereomatchingkiss/mlpack,thirdwing/mlpack,minhpqn/mlpack,trungda/mlpack,trungda/mlpack,chenmoshushi/mlpack,chenmoshushi/mlpack,ajjl/mlpack,stereomatchingkiss/mlpack,ajjl/mlpack,ersanliqiao/mlpack,darcyliu/mlpack,datachand/mlpack,BookChan/mlpack,palashahuja/mlpack,erubboli/mlpack,bmswgnp/mlpack,ranjan1990/mlpack,BookChan/mlpack,stereomatchingkiss/mlpack,erubboli/mlpack,ajjl/mlpack,thirdwing/mlpack,ersanliqiao/mlpack,datachand/mlpack,lezorich/mlpack,lezorich/mlpack,lezorich/mlpack,minhpqn/mlpack,darcyliu/mlpack,erubboli/mlpack,ranjan1990/mlpack,Azizou/mlpack,bmswgnp/mlpack