!8053 Revert changes to weighted_random_sampler in PR7866

Merge pull request !8053 from ZiruiWu/revert_some_changes_in_7866

mindspore/ccsrc/minddata/dataset/engine/datasetops/source/sampler/weighted_random_sampler.cc

@@ -49,16 +49,6 @@ Status WeightedRandomSampler::InitSampler() {
                                "Invalid parameter, samples_per_buffer must be greater than 0, but got " +
                                  std::to_string(samples_per_buffer_) + ".\n");
 
-  CHECK_FAIL_RETURN_UNEXPECTED(weights_.size() != 0, "Invalid parameter, weights size must not be 0.\n");
-  int32_t zero_elem = 0;
-  for (auto &elem : weights_) {
-    CHECK_FAIL_RETURN_UNEXPECTED(elem >= 0.0, "Invalid parameter, weights must not contain negative number, but got " +
-                                                std::to_string(elem) + ".\n");
-    if (elem == 0.0) zero_elem++;
-  }
-  CHECK_FAIL_RETURN_UNEXPECTED(zero_elem != weights_.size(),
-                               "Invalid parameter, elements of weights must not be all zero.\n");
-
   if (weights_.size() > static_cast<size_t>(num_rows_)) {
     return Status(StatusCode::kUnexpectedError, __LINE__, __FILE__,
                   "Invalid parameter, size of sample weights must be less than or equal to num of data, "