Reverse ordering to read out error in sampling measure (Qiskit#2003)

* reverse ordering of read out error in sampling measure * fix batch check --------- Co-authored-by: Hiroshi Horii <[email protected]>
doichanj · Nov 22, 2023 · e30bedb · e30bedb
1 parent a261af2
commit e30bedb
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Showing 4 changed files with 10 additions and 3 deletions.
diff --git a/releasenotes/notes/fix_sample_measure_roerr-747b955aa2bf778c.yaml b/releasenotes/notes/fix_sample_measure_roerr-747b955aa2bf778c.yaml
@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Fixes order of applying read out error in sampling measure
+    in circuit executors. Ordering is reversed to fit to the older verison
+    of Aer.
+    Also fixed check of bacth execution.
diff --git a/src/simulators/batch_shots_executor.hpp b/src/simulators/batch_shots_executor.hpp
@@ -150,7 +150,7 @@ template <class state_t>
 void BatchShotsExecutor<state_t>::run_circuit_with_sampling(
     Circuit &circ, const Config &config, RngEngine &init_rng,
     ResultItr result_it) {
-  if (circ.num_bind_params == 1 || !enable_batch_multi_shots_) {
+  if (!enable_batch_multi_shots_) {
     return Executor<state_t>::run_circuit_with_sampling(circ, config, init_rng,
                                                         result_it);
   }

diff --git a/src/simulators/circuit_executor.hpp b/src/simulators/circuit_executor.hpp
@@ -1073,7 +1073,7 @@ void Executor<state_t>::measure_sampler(InputIterator first_meas,
   uint_t num_registers =
       (register_map.empty()) ? 0ULL : 1 + register_map.rbegin()->first;
   ClassicalRegister creg;
-  for (int_t i = 0; i < all_samples.size(); i++) {
+  for (int_t i = all_samples.size() - 1; i >= 0; i--) {
     creg.initialize(num_memory, num_registers);
 
     // process memory bit measurements

diff --git a/src/simulators/multi_state_executor.hpp b/src/simulators/multi_state_executor.hpp
@@ -863,7 +863,7 @@ void MultiStateExecutor<state_t>::measure_sampler(InputIterator first_meas,
       (memory_map.empty()) ? 0ULL : 1 + memory_map.rbegin()->first;
   uint_t num_registers =
       (register_map.empty()) ? 0ULL : 1 + register_map.rbegin()->first;
-  for (int_t i = 0; i < all_samples.size(); i++) {
+  for (int_t i = all_samples.size() - 1; i >= 0; i--) {
     ClassicalRegister creg = state.creg();
 
     // process memory bit measurements