diff --git a/src/Action_Rotate.cpp b/src/Action_Rotate.cpp
index e365074ee8..786b9c925d 100644
--- a/src/Action_Rotate.cpp
+++ b/src/Action_Rotate.cpp
@@ -38,6 +38,7 @@ int Action_Rotate::Get3x3Set(DataSetList const& DSL, std::string const& dsname)
     mprinterr("Error: No 3x3 matrices data set '%s'\n", dsname.c_str());
     return 1;
   }
+  parallelNum_.SetForParallel( rmatrices_ );
   return 0;
 }
 
@@ -201,29 +202,31 @@ Action::RetType Action_Rotate::DoAction(int frameNum, ActionFrame& frm) {
     if (all_atoms_selected_)
       frm.ModifyFrm().ModifyBox().RotateUcell( RotMatrix_ );
   } else if (mode_ == DATASET) {
+    int dsidx = parallelNum_.ParallelFrameNum(frameNum, frm.TrajoutNum());
     // Rotate coordinates using rotation matrices in DataSet
-    if (frm.TrajoutNum() >= (int)rmatrices_->Size()) {
-      mprintf("Warning: Frame %i out of range for set '%s'\n",
+    if (dsidx >= (int)rmatrices_->Size()) {
+      rprintf("Warning: Frame %i out of range for set '%s'\n",
               frm.TrajoutNum()+1, rmatrices_->legend());
       return Action::ERR;
     }
     if (inverse_) {
-      frm.ModifyFrm().InverseRotate((*rmatrices_)[frm.TrajoutNum()], mask_);
+      frm.ModifyFrm().InverseRotate((*rmatrices_)[dsidx], mask_);
       if (all_atoms_selected_)
-        frm.ModifyFrm().ModifyBox().InverseRotateUcell( (*rmatrices_)[frm.TrajoutNum()] );
+        frm.ModifyFrm().ModifyBox().InverseRotateUcell( (*rmatrices_)[dsidx] );
     } else {
-      frm.ModifyFrm().Rotate((*rmatrices_)[frm.TrajoutNum()], mask_);
+      frm.ModifyFrm().Rotate((*rmatrices_)[dsidx], mask_);
       if (all_atoms_selected_)
-        frm.ModifyFrm().ModifyBox().RotateUcell( (*rmatrices_)[frm.TrajoutNum()] );
+        frm.ModifyFrm().ModifyBox().RotateUcell( (*rmatrices_)[dsidx] );
     }
   } else if (mode_ == CALC) {
+    int dsidx = parallelNum_.ParallelFrameNum(frameNum, frm.TrajoutNum());
     // Calculate rotations around X Y and Z axes from rotation matrices in DataSet
-    if (frm.TrajoutNum() >= (int)rmatrices_->Size()) {
-      mprintf("Warning: Frame %i out of range for set '%s'\n",
+    if (dsidx >= (int)rmatrices_->Size()) {
+      rprintf("Warning: Frame %i out of range for set '%s'\n",
               frm.TrajoutNum()+1, rmatrices_->legend());
       return Action::ERR;
     }
-    Matrix_3x3 const& RM = (*rmatrices_)[frm.TrajoutNum()];
+    Matrix_3x3 const& RM = (*rmatrices_)[dsidx];
     double tx, ty, tz;
     RM.RotationAngles(tx, ty, tz);
     tx *= Constants::RADDEG;
diff --git a/src/Action_Rotate.h b/src/Action_Rotate.h
index cbee2be97e..f868a91477 100644
--- a/src/Action_Rotate.h
+++ b/src/Action_Rotate.h
@@ -1,6 +1,7 @@
 #ifndef INC_ACTION_ROTATE_H
 #define INC_ACTION_ROTATE_H
 #include "Action.h"
+#include "ParallelSetFrameNum.h"
 class DataSet_Mat3x3;
 /// Rotate coordinates or calculate rotations from rotation matrices
 class Action_Rotate : public Action {
@@ -33,5 +34,6 @@ class Action_Rotate : public Action {
     DataSet* dsout_ty_;         ///< Hold output theta Y (calc)
     DataSet* dsout_tz_;         ///< Hold output theta Z (calc)
     DataSet* dsout_t_;          ///< Hold output theta (calc)
+    Cpptraj::ParallelSetFrameNum parallelNum_;
 };
 #endif
diff --git a/src/ParallelSetFrameNum.cpp b/src/ParallelSetFrameNum.cpp
new file mode 100644
index 0000000000..53e841bba5
--- /dev/null
+++ b/src/ParallelSetFrameNum.cpp
@@ -0,0 +1,21 @@
+#include "ParallelSetFrameNum.h"
+#include "CpptrajStdio.h"
+#include "DataSet.h"
+using namespace Cpptraj;
+
+void ParallelSetFrameNum::SetForParallel(DataSet const* setIn) {
+  set_ = setIn;
+# ifdef MPI
+  // In parallel, number to use will depend on whether the set exists or not
+  if (set_->Size() > 0)
+    exists_ = true;
+  else
+    exists_ = false;
+# ifdef DEBUG_CPPTRAJ_PARALLELSETFRAMENUM
+  if (!exists_)
+    rprintf("DEBUG: Set '%s' does not yet exist.\n", set_->legend());
+  else
+    rprintf("DEBUG: Set '%s' exists with size %zu.\n", set_->legend(), set_->Size());
+# endif
+# endif /*MPI */
+}
diff --git a/src/ParallelSetFrameNum.h b/src/ParallelSetFrameNum.h
new file mode 100644
index 0000000000..535980dce8
--- /dev/null
+++ b/src/ParallelSetFrameNum.h
@@ -0,0 +1,38 @@
+#ifndef INC_PARALLELSETFRAMENUM_H
+#define INC_PARALLELSETFRAMENUM_H
+class DataSet;
+namespace Cpptraj {
+/// Used to pick the correct frame from a data set in parallel
+/** In parallel, Actions that access data from DataSets need to handle
+  * two cases:
+  *   1) The data set exists already before trajectory processing.
+  *   2) The data set is being created during trajectory processing.
+  * In case 1, the data set should be accessed using ActionFrame::TrajoutNum().
+  * In case 2, the data set should be accessed using the frameNum variable
+  * since the set has not yet been synced.
+  */
+class ParallelSetFrameNum {
+  public:
+    /// CONSTRUCTOR
+    ParallelSetFrameNum() : set_(0), exists_(false) {}
+    /// Initialize with DataSet, record if it has any data yet.
+    void SetForParallel(DataSet const*);
+    /// \return Correct frame number in parallel based on whether set exists or is being generated
+    int ParallelFrameNum(int frameNum, int trajoutNum) const {
+#     ifdef MPI
+      // In parallel, number to use depends on whether the set is being generated or not.
+      if (exists_)
+        return trajoutNum;
+      else
+        return frameNum;
+#     else
+      // In serial, just return the frame number.
+      return frameNum;
+#     endif
+    }
+  private:
+    DataSet const* set_; ///< The DataSet in question
+    bool exists_;  ///< True if set exists, false if it is being generated.
+};
+} // END namespace Cpptraj
+#endif
diff --git a/src/Version.h b/src/Version.h
index 355123d3f4..b8aecef7f6 100644
--- a/src/Version.h
+++ b/src/Version.h
@@ -12,7 +12,7 @@
  * Whenever a number that precedes <revision> is incremented, all subsequent
  * numbers should be reset to 0.
  */
-#define CPPTRAJ_INTERNAL_VERSION "V6.29.5"
+#define CPPTRAJ_INTERNAL_VERSION "V6.29.6"
 /// PYTRAJ relies on this
 #define CPPTRAJ_VERSION_STRING CPPTRAJ_INTERNAL_VERSION
 #endif
diff --git a/src/cpptrajdepend b/src/cpptrajdepend
index f80b0a290f..37223a244f 100644
--- a/src/cpptrajdepend
+++ b/src/cpptrajdepend
@@ -73,7 +73,7 @@ Action_RandomizeIons.o : Action_RandomizeIons.cpp Action.h ActionState.h Action_
 Action_Remap.o : Action_Remap.cpp Action.h ActionState.h ActionTopWriter.h Action_Remap.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_1D.h DataSet_Coords.h DataSet_Coords_REF.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
 Action_ReplicateCell.o : Action_ReplicateCell.cpp Action.h ActionFrameCounter.h ActionState.h ActionTopWriter.h Action_ReplicateCell.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h OutputTrajCommon.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TrajectoryFile.h Trajout_Single.h TypeNameHolder.h Unit.h Vec3.h
 Action_Rmsd.o : Action_Rmsd.cpp Action.h ActionState.h Action_Rmsd.h ArgList.h ArrayIterator.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h ComplexArray.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_1D.h DataSet_Coords.h DataSet_Coords_REF.h DataSet_Mesh.h DataSet_Vector.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceAction.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h Spline.h StringRoutines.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
-Action_Rotate.o : Action_Rotate.cpp Action.h ActionState.h Action_Rotate.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h DataSet_Mat3x3.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
+Action_Rotate.o : Action_Rotate.cpp Action.h ActionState.h Action_Rotate.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h DataSet_Mat3x3.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParallelSetFrameNum.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
 Action_RunningAvg.o : Action_RunningAvg.cpp Action.h ActionState.h Action_RunningAvg.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
 Action_STFC_Diffusion.o : Action_STFC_Diffusion.cpp Action.h ActionState.h Action_STFC_Diffusion.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h Dimension.h DispatchObject.h DistRoutines.h FileIO.h FileName.h FileTypes.h Frame.h ImageOption.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
 Action_Scale.o : Action_Scale.cpp Action.h ActionState.h Action_Scale.h ArgList.h AssociatedData.h Atom.h AtomMask.h AtomType.h BaseIOtype.h Box.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h DataFile.h DataFileList.h DataSet.h DataSetList.h DataSet_Coords.h DataSet_Coords_REF.h Dimension.h DispatchObject.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h MetaData.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReferenceFrame.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Timer.h Topology.h TypeNameHolder.h Unit.h Vec3.h
@@ -190,7 +190,7 @@ ClusterMap.o : ClusterMap.cpp AssociatedData.h ClusterMap.h Constants.h CpptrajF
 Cmd.o : Cmd.cpp Cmd.h DispatchObject.h
 CmdInput.o : CmdInput.cpp CmdInput.h StringRoutines.h
 CmdList.o : CmdList.cpp Cmd.h CmdList.h DispatchObject.h
-Command.o : Command.cpp Action.h ActionFrameCounter.h ActionList.h ActionState.h ActionTopWriter.h Action_AddAtom.h Action_Align.h Action_Angle.h Action_AreaPerMol.h Action_AtomMap.h Action_AtomicCorr.h Action_AtomicFluct.h Action_AutoImage.h Action_Average.h Action_AvgBox.h Action_Bounds.h Action_Box.h Action_Center.h Action_Channel.h Action_CheckChirality.h Action_CheckStructure.h Action_Closest.h Action_ClusterDihedral.h Action_Contacts.h Action_CreateCrd.h Action_CreateReservoir.h Action_DNAionTracker.h Action_DSSP.h Action_Density.h Action_Diffusion.h Action_Dihedral.h Action_DihedralRMS.h Action_Dipole.h Action_DistRmsd.h Action_Distance.h Action_EneDecomp.h Action_Energy.h Action_Esander.h Action_FilterByData.h Action_FixAtomOrder.h Action_FixImagedBonds.h Action_GIST.h Action_Grid.h Action_GridFreeEnergy.h Action_HydrogenBond.h Action_Image.h Action_InfraredSpectrum.h Action_Jcoupling.h Action_Keep.h Action_LESsplit.h Action_LIE.h Action_LipidOrder.h Action_MakeStructure.h Action_Mask.h Action_Matrix.h Action_MinImage.h Action_MinMaxDist.h Action_Molsurf.h Action_MultiDihedral.h Action_MultiPucker.h Action_MultiVector.h Action_NAstruct.h Action_NMRrst.h Action_NativeContacts.h Action_OrderParameter.h Action_Outtraj.h Action_PairDist.h Action_Pairwise.h Action_Principal.h Action_Projection.h Action_Pucker.h Action_Radgyr.h Action_Radial.h Action_RandomizeIons.h Action_Remap.h Action_ReplicateCell.h Action_Rmsd.h Action_Rotate.h Action_RunningAvg.h Action_STFC_Diffusion.h Action_Scale.h Action_SetVelocity.h Action_Spam.h Action_Strip.h Action_Surf.h Action_SymmetricRmsd.h Action_Temperature.h Action_Time.h Action_ToroidalDiffusion.h Action_Translate.h Action_Unstrip.h Action_Unwrap.h Action_Vector.h Action_VelocityAutoCorr.h Action_Volmap.h Action_Volume.h Action_Watershell.h Action_XtalSymm.h Analysis.h AnalysisList.h AnalysisState.h Analysis_AmdBias.h Analysis_AutoCorr.h Analysis_Average.h Analysis_CalcDiffusion.h Analysis_Clustering.h Analysis_ConstantPHStats.h Analysis_Corr.h Analysis_CrankShaft.h Analysis_CrdFluct.h Analysis_CrossCorr.h Analysis_CurveFit.h Analysis_Divergence.h Analysis_EvalPlateau.h Analysis_FFT.h Analysis_HausdorffDistance.h Analysis_Hist.h Analysis_IRED.h Analysis_Integrate.h Analysis_KDE.h Analysis_Lifetime.h Analysis_LowestCurve.h Analysis_Matrix.h Analysis_MeltCurve.h Analysis_Modes.h Analysis_MultiHist.h Analysis_Multicurve.h Analysis_Overlap.h Analysis_PhiPsi.h Analysis_Project.h Analysis_Regression.h Analysis_RemLog.h Analysis_Rms2d.h Analysis_RmsAvgCorr.h Analysis_Rotdif.h Analysis_RunningAvg.h Analysis_Slope.h Analysis_Spline.h Analysis_State.h Analysis_Statistics.h Analysis_TI.h Analysis_TICA.h Analysis_Timecorr.h Analysis_VectorMath.h Analysis_Wavelet.h ArgList.h Array1D.h ArrayIterator.h AssociatedData.h Atom.h AtomMap.h AtomMask.h AtomType.h AxisType.h BaseIOtype.h Box.h BoxArgs.h BufferedLine.h CharMask.h Cluster/Algorithm.h Cluster/BestReps.h Cluster/CentroidArray.h Cluster/Cframes.h Cluster/Control.h Cluster/DrawGraph.h Cluster/List.h Cluster/Metric.h Cluster/MetricArray.h Cluster/Node.h Cluster/Sieve.h Cluster/Silhouette.h ClusterMap.h Cmd.h CmdInput.h CmdList.h Command.h CompactFrameArray.h ComplexArray.h Constants.h Constraints.h ControlBlock.h ControlBlock_For.h CoordinateInfo.h Corr.h Cph.h CpptrajFile.h CpptrajState.h CpptrajStdio.h DataFile.h DataFileList.h DataFilter.h DataSet.h DataSetList.h DataSet_1D.h DataSet_2D.h DataSet_3D.h DataSet_Coords.h DataSet_Coords_CRD.h DataSet_Coords_REF.h DataSet_GridFlt.h DataSet_MatrixDbl.h DataSet_MatrixFlt.h DataSet_Mesh.h DataSet_Modes.h DataSet_RemLog.h DataSet_Vector.h DataSet_double.h DataSet_float.h DataSet_integer.h DataSet_integer_mem.h DataSet_pH.h DataSet_string.h Deprecated.h DiffusionResults.h DihedralSearch.h Dimension.h DispatchObject.h Energy.h Energy/Ecalc_Nonbond.h Energy/EnergyDecomposer.h Energy/ErfcFxn.h Energy/EwaldParams.h Energy/PME_RecipParams.h Energy/VDW_LongRange_Correction.h Energy_Sander.h EnsembleIn.h EnsembleOutList.h EwaldOptions.h ExclusionArray.h Exec.h Exec_AddMissingRes.h Exec_Analyze.h Exec_Calc.h Exec_CatCrd.h Exec_Change.h Exec_ClusterMap.h Exec_CombineCoords.h Exec_Commands.h Exec_CompareClusters.h Exec_CompareEnergy.h Exec_CompareTop.h Exec_CrdAction.h Exec_CrdOut.h Exec_CrdTransform.h Exec_CreateSet.h Exec_DataFile.h Exec_DataFilter.h Exec_DataSetCmd.h Exec_Emin.h Exec_ExtendedComparison.h Exec_Flatten.h Exec_GenerateAmberRst.h Exec_Graft.h Exec_Help.h Exec_HmassRepartition.h Exec_LoadCrd.h Exec_LoadTraj.h Exec_ParallelAnalysis.h Exec_ParmBox.h Exec_ParmSolvent.h Exec_ParmStrip.h Exec_ParmWrite.h Exec_ParseTiming.h Exec_PermuteDihedrals.h Exec_Precision.h Exec_PrepareForLeap.h Exec_PrintData.h Exec_Random.h Exec_ReadData.h Exec_ReadEnsembleData.h Exec_ReadInput.h Exec_RotateDihedral.h Exec_RunAnalysis.h Exec_ScaleDihedralK.h Exec_Sequence.h Exec_SequenceAlign.h Exec_Set.h Exec_Show.h Exec_SortEnsembleData.h Exec_SplitCoords.h Exec_System.h Exec_Top.h Exec_Traj.h Exec_UpdateParameters.h Exec_ViewRst.h Exec_Zmatrix.h ExtendedSimilarity.h FileIO.h FileName.h FileTypes.h Frame.h FramePtrArray.h GIST_PME.h Grid.h GridAction.h GridBin.h GridMover.h HistBin.h Hungarian.h ImageOption.h ImageTypes.h InputTrajCommon.h InteractionData.h MapAtom.h MaskArray.h MaskToken.h Matrix.h Matrix_3x3.h MetaData.h Molecule.h NC_Routines.h NameType.h NetcdfFile.h OnlineVarT.h OutputTrajCommon.h PDBfile.h PairList.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h PubFFT.h Pucker.h Pucker_PuckerMask.h Pucker_PuckerSearch.h Pucker_PuckerToken.h RPNcalc.h Random.h Range.h ReferenceAction.h ReferenceFrame.h RemdReservoirNC.h ReplicaDimArray.h ReplicaInfo.h Residue.h Segment.h Spline.h SplineFxnTable.h StructureCheck.h SymbolExporting.h SymmetricRmsdCalc.h TextFormat.h Timer.h Topology.h TrajFrameCounter.h TrajectoryFile.h Trajin.h TrajinList.h TrajoutList.h Trajout_Single.h TypeNameHolder.h Unit.h Vec3.h cuda_kernels/GistCudaSetup.cuh helpme_standalone.h molsurf.h
+Command.o : Command.cpp Action.h ActionFrameCounter.h ActionList.h ActionState.h ActionTopWriter.h Action_AddAtom.h Action_Align.h Action_Angle.h Action_AreaPerMol.h Action_AtomMap.h Action_AtomicCorr.h Action_AtomicFluct.h Action_AutoImage.h Action_Average.h Action_AvgBox.h Action_Bounds.h Action_Box.h Action_Center.h Action_Channel.h Action_CheckChirality.h Action_CheckStructure.h Action_Closest.h Action_ClusterDihedral.h Action_Contacts.h Action_CreateCrd.h Action_CreateReservoir.h Action_DNAionTracker.h Action_DSSP.h Action_Density.h Action_Diffusion.h Action_Dihedral.h Action_DihedralRMS.h Action_Dipole.h Action_DistRmsd.h Action_Distance.h Action_EneDecomp.h Action_Energy.h Action_Esander.h Action_FilterByData.h Action_FixAtomOrder.h Action_FixImagedBonds.h Action_GIST.h Action_Grid.h Action_GridFreeEnergy.h Action_HydrogenBond.h Action_Image.h Action_InfraredSpectrum.h Action_Jcoupling.h Action_Keep.h Action_LESsplit.h Action_LIE.h Action_LipidOrder.h Action_MakeStructure.h Action_Mask.h Action_Matrix.h Action_MinImage.h Action_MinMaxDist.h Action_Molsurf.h Action_MultiDihedral.h Action_MultiPucker.h Action_MultiVector.h Action_NAstruct.h Action_NMRrst.h Action_NativeContacts.h Action_OrderParameter.h Action_Outtraj.h Action_PairDist.h Action_Pairwise.h Action_Principal.h Action_Projection.h Action_Pucker.h Action_Radgyr.h Action_Radial.h Action_RandomizeIons.h Action_Remap.h Action_ReplicateCell.h Action_Rmsd.h Action_Rotate.h Action_RunningAvg.h Action_STFC_Diffusion.h Action_Scale.h Action_SetVelocity.h Action_Spam.h Action_Strip.h Action_Surf.h Action_SymmetricRmsd.h Action_Temperature.h Action_Time.h Action_ToroidalDiffusion.h Action_Translate.h Action_Unstrip.h Action_Unwrap.h Action_Vector.h Action_VelocityAutoCorr.h Action_Volmap.h Action_Volume.h Action_Watershell.h Action_XtalSymm.h Analysis.h AnalysisList.h AnalysisState.h Analysis_AmdBias.h Analysis_AutoCorr.h Analysis_Average.h Analysis_CalcDiffusion.h Analysis_Clustering.h Analysis_ConstantPHStats.h Analysis_Corr.h Analysis_CrankShaft.h Analysis_CrdFluct.h Analysis_CrossCorr.h Analysis_CurveFit.h Analysis_Divergence.h Analysis_EvalPlateau.h Analysis_FFT.h Analysis_HausdorffDistance.h Analysis_Hist.h Analysis_IRED.h Analysis_Integrate.h Analysis_KDE.h Analysis_Lifetime.h Analysis_LowestCurve.h Analysis_Matrix.h Analysis_MeltCurve.h Analysis_Modes.h Analysis_MultiHist.h Analysis_Multicurve.h Analysis_Overlap.h Analysis_PhiPsi.h Analysis_Project.h Analysis_Regression.h Analysis_RemLog.h Analysis_Rms2d.h Analysis_RmsAvgCorr.h Analysis_Rotdif.h Analysis_RunningAvg.h Analysis_Slope.h Analysis_Spline.h Analysis_State.h Analysis_Statistics.h Analysis_TI.h Analysis_TICA.h Analysis_Timecorr.h Analysis_VectorMath.h Analysis_Wavelet.h ArgList.h Array1D.h ArrayIterator.h AssociatedData.h Atom.h AtomMap.h AtomMask.h AtomType.h AxisType.h BaseIOtype.h Box.h BoxArgs.h BufferedLine.h CharMask.h Cluster/Algorithm.h Cluster/BestReps.h Cluster/CentroidArray.h Cluster/Cframes.h Cluster/Control.h Cluster/DrawGraph.h Cluster/List.h Cluster/Metric.h Cluster/MetricArray.h Cluster/Node.h Cluster/Sieve.h Cluster/Silhouette.h ClusterMap.h Cmd.h CmdInput.h CmdList.h Command.h CompactFrameArray.h ComplexArray.h Constants.h Constraints.h ControlBlock.h ControlBlock_For.h CoordinateInfo.h Corr.h Cph.h CpptrajFile.h CpptrajState.h CpptrajStdio.h DataFile.h DataFileList.h DataFilter.h DataSet.h DataSetList.h DataSet_1D.h DataSet_2D.h DataSet_3D.h DataSet_Coords.h DataSet_Coords_CRD.h DataSet_Coords_REF.h DataSet_GridFlt.h DataSet_MatrixDbl.h DataSet_MatrixFlt.h DataSet_Mesh.h DataSet_Modes.h DataSet_RemLog.h DataSet_Vector.h DataSet_double.h DataSet_float.h DataSet_integer.h DataSet_integer_mem.h DataSet_pH.h DataSet_string.h Deprecated.h DiffusionResults.h DihedralSearch.h Dimension.h DispatchObject.h Energy.h Energy/Ecalc_Nonbond.h Energy/EnergyDecomposer.h Energy/ErfcFxn.h Energy/EwaldParams.h Energy/PME_RecipParams.h Energy/VDW_LongRange_Correction.h Energy_Sander.h EnsembleIn.h EnsembleOutList.h EwaldOptions.h ExclusionArray.h Exec.h Exec_AddMissingRes.h Exec_Analyze.h Exec_Calc.h Exec_CatCrd.h Exec_Change.h Exec_ClusterMap.h Exec_CombineCoords.h Exec_Commands.h Exec_CompareClusters.h Exec_CompareEnergy.h Exec_CompareTop.h Exec_CrdAction.h Exec_CrdOut.h Exec_CrdTransform.h Exec_CreateSet.h Exec_DataFile.h Exec_DataFilter.h Exec_DataSetCmd.h Exec_Emin.h Exec_ExtendedComparison.h Exec_Flatten.h Exec_GenerateAmberRst.h Exec_Graft.h Exec_Help.h Exec_HmassRepartition.h Exec_LoadCrd.h Exec_LoadTraj.h Exec_ParallelAnalysis.h Exec_ParmBox.h Exec_ParmSolvent.h Exec_ParmStrip.h Exec_ParmWrite.h Exec_ParseTiming.h Exec_PermuteDihedrals.h Exec_Precision.h Exec_PrepareForLeap.h Exec_PrintData.h Exec_Random.h Exec_ReadData.h Exec_ReadEnsembleData.h Exec_ReadInput.h Exec_RotateDihedral.h Exec_RunAnalysis.h Exec_ScaleDihedralK.h Exec_Sequence.h Exec_SequenceAlign.h Exec_Set.h Exec_Show.h Exec_SortEnsembleData.h Exec_SplitCoords.h Exec_System.h Exec_Top.h Exec_Traj.h Exec_UpdateParameters.h Exec_ViewRst.h Exec_Zmatrix.h ExtendedSimilarity.h FileIO.h FileName.h FileTypes.h Frame.h FramePtrArray.h GIST_PME.h Grid.h GridAction.h GridBin.h GridMover.h HistBin.h Hungarian.h ImageOption.h ImageTypes.h InputTrajCommon.h InteractionData.h MapAtom.h MaskArray.h MaskToken.h Matrix.h Matrix_3x3.h MetaData.h Molecule.h NC_Routines.h NameType.h NetcdfFile.h OnlineVarT.h OutputTrajCommon.h PDBfile.h PairList.h Parallel.h ParallelSetFrameNum.h ParameterHolders.h ParameterSet.h ParameterTypes.h PubFFT.h Pucker.h Pucker_PuckerMask.h Pucker_PuckerSearch.h Pucker_PuckerToken.h RPNcalc.h Random.h Range.h ReferenceAction.h ReferenceFrame.h RemdReservoirNC.h ReplicaDimArray.h ReplicaInfo.h Residue.h Segment.h Spline.h SplineFxnTable.h StructureCheck.h SymbolExporting.h SymmetricRmsdCalc.h TextFormat.h Timer.h Topology.h TrajFrameCounter.h TrajectoryFile.h Trajin.h TrajinList.h TrajoutList.h Trajout_Single.h TypeNameHolder.h Unit.h Vec3.h cuda_kernels/GistCudaSetup.cuh helpme_standalone.h molsurf.h
 CompactFrameArray.o : CompactFrameArray.cpp Box.h CompactFrameArray.h CoordinateInfo.h CpptrajStdio.h Matrix_3x3.h Parallel.h ReplicaDimArray.h Vec3.h
 ComplexArray.o : ComplexArray.cpp ArrayIterator.h ComplexArray.h
 Constraints.o : Constraints.cpp ArgList.h Atom.h AtomMask.h AtomType.h Box.h CharMask.h Constants.h Constraints.h CoordinateInfo.h CpptrajStdio.h FileName.h Frame.h MaskToken.h Matrix_3x3.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h Range.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h Topology.h TypeNameHolder.h Unit.h Vec3.h
@@ -412,6 +412,7 @@ PDBfile.o : PDBfile.cpp Atom.h CpptrajFile.h CpptrajStdio.h FileIO.h FileName.h
 PairList.o : PairList.cpp Atom.h AtomMask.h Box.h CoordinateInfo.h CpptrajStdio.h Frame.h MaskToken.h Matrix_3x3.h Molecule.h NameType.h PairList.h Parallel.h ReplicaDimArray.h Residue.h Segment.h StringRoutines.h SymbolExporting.h Timer.h Unit.h Vec3.h
 Parallel.o : Parallel.cpp Parallel.h
 ParallelNetcdf.o : ParallelNetcdf.cpp CpptrajStdio.h Parallel.h ParallelNetcdf.h
+ParallelSetFrameNum.o : ParallelSetFrameNum.cpp AssociatedData.h CpptrajFile.h CpptrajStdio.h DataSet.h Dimension.h FileIO.h FileName.h MetaData.h Parallel.h ParallelSetFrameNum.h Range.h TextFormat.h
 ParameterSet.o : ParameterSet.cpp AtomType.h Constants.h CpptrajFile.h CpptrajStdio.h FileIO.h FileName.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h TypeNameHolder.h UpdateParameters.h
 ParmFile.o : ParmFile.cpp ArgList.h Atom.h AtomMask.h AtomType.h BaseIOtype.h BondSearch.h Box.h BufferedFrame.h BufferedLine.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h FileIO.h FileName.h FileTypes.h Frame.h MaskToken.h Matrix_3x3.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h ParmFile.h ParmIO.h Parm_Amber.h Parm_CIF.h Parm_CharmmPsf.h Parm_Gromacs.h Parm_Mol2.h Parm_PDB.h Parm_SDF.h Parm_Tinker.h Range.h ReplicaDimArray.h Residue.h Segment.h SymbolExporting.h TextFormat.h Topology.h TypeNameHolder.h Unit.h Vec3.h
 Parm_Amber.o : Parm_Amber.cpp ArgList.h Atom.h AtomMask.h AtomType.h BaseIOtype.h BondSearch.h Box.h BufferedFrame.h Constants.h CoordinateInfo.h CpptrajFile.h CpptrajStdio.h ExclusionArray.h FileIO.h FileName.h Frame.h MaskToken.h Matrix_3x3.h Molecule.h NameType.h Parallel.h ParameterHolders.h ParameterSet.h ParameterTypes.h ParmIO.h Parm_Amber.h Range.h ReplicaDimArray.h Residue.h Segment.h StringRoutines.h SymbolExporting.h TextFormat.h Topology.h TypeNameHolder.h Unit.h Vec3.h
diff --git a/src/cpptrajfiles b/src/cpptrajfiles
index ddfc01d3fe..2ebe0e7cde 100644
--- a/src/cpptrajfiles
+++ b/src/cpptrajfiles
@@ -368,6 +368,7 @@ COMMON_SOURCES= \
         PairList.cpp \
         Parallel.cpp \
         ParallelNetcdf.cpp \
+        ParallelSetFrameNum.cpp \
         ParmFile.cpp \
         Parm_Amber.cpp \
         Parm_CharmmPsf.cpp \