diff --git a/regtests/matrix_pdlib b/regtests/matrix_pdlib
new file mode 100644
index 000000000..683caa307
--- /dev/null
+++ b/regtests/matrix_pdlib
@@ -0,0 +1,109 @@
+#!/bin/sh
+
+#SBATCH -n 40
+#SBATCH -q batch
+#SBATCH -t 04:00:00
+#SBATCH -A marine-cpu
+#SBATCH -J w3_pdlib
+#SBATCH -o w3_pdlib.out
+
+
+  REGDIR=/scratch1/NCEPDEV/climate/Matthew.Masarik/projs/reproduce_mpi/regtest_ww3_ufs1.1-unstr/runs/ww3-blk-exp-02/regtests
+
+  module purge
+  module load cmake/3.20.1
+  module load intel/2022.1.2
+  module load impi/2022.1.2
+  module use  /scratch1/NCEPDEV/nems/role.epic/hpc-stack/libs/intel-2022.1.2/modulefiles/stack
+  module load hpc/1.2.0
+  module load hpc-intel/2022.1.2
+  module load hpc-impi/2022.1.2
+  module load libpng/1.6.37
+  module load zlib/1.2.11
+  module load jasper/2.0.25
+  module load hdf5/1.10.6
+  module load netcdf/4.7.4
+  module load bacio/2.4.1
+  module load g2/3.4.5
+  module load w3emc/2.9.2
+  module load esmf/8.3.0b09
+  export METIS_PATH=/scratch1/NCEPDEV/climate/Matthew.Masarik/waves/opt/hpc-stack/parmetis-4.0.3/install
+  export SCOTCH_PATH=/scratch1/NCEPDEV/climate/Matthew.Masarik/waves/opt/hpc-stack/scotch-v7.0.3/install
+  export path_build_root=$REGDIR/build
+
+  function run_pdlib() {
+      if [ $# -ne 3 ]; then
+          echo 'usage: run_pdlib <nprocs> <worktag> <grid>'
+          return
+      fi
+      local nprocs=$1
+      local worktag=$2
+      local grid=$3
+      ./bin/run_cmake_test -b slurm -o all -S -T -s MPI -s PDLIB -i input_unstr -w work_${grid}_${nprocs}_${worktag} -g $grid -f -p srun -n $nprocs ../model ww3_ufs1.1
+      return
+  }
+
+  function cmp_pdlib() {
+      if [ $# -ne 2 ]; then
+          echo 'usage: cmp_pdlib <wrkdir1> <wrkdir2>'
+          return
+      fi
+      local wrkdir1=$1
+      local wrkdir2=$2
+      ./bin/test.comp ww3_ufs1.1 work_${wrkdir1} work_${wrkdir2}
+      return
+  }
+
+
+  echo ' '
+  echo '             **********************************************'
+  echo '           ***     WAVEWATCH III    -     PDLIB           ***'
+  echo '             **********************************************'
+  echo ' '
+
+  cd $REGDIR
+  [[ -d ${path_build_root} ]] && rm -rf ${path_build_root}
+
+  # A-RUN1: 39 vs. 40
+  GRD="a"
+  TAG="run1"
+  NP0=39
+  NP1=40
+  run_pdlib ${NP0} ${TAG} $GRD
+  run_pdlib ${NP1} ${TAG} $GRD
+  cmp_pdlib ${GRD}_${NP0}_${TAG} ${GRD}_${NP1}_${TAG}
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP0}_${TAG}/*
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP1}_${TAG}/*
+
+
+  # B-RUN1: 39 vs. 40
+  GRD="b"
+  TAG="run1"
+  NP0=39
+  NP1=40
+  run_pdlib ${NP0} ${TAG} $GRD
+  run_pdlib ${NP1} ${TAG} $GRD
+  cmp_pdlib ${GRD}_${NP0}_${TAG} ${GRD}_${NP1}_${TAG}
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP0}_${TAG}/*
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP1}_${TAG}/*
+
+  # C-RUN1: 39 vs. 40
+  GRD="c"
+  TAG="run1"
+  NP0=39
+  NP1=40
+  run_pdlib ${NP0} ${TAG} $GRD
+  run_pdlib ${NP1} ${TAG} $GRD
+  cmp_pdlib ${GRD}_${NP0}_${TAG} ${GRD}_${NP1}_${TAG}
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP0}_${TAG}/*
+  du -hs $REGDIR/ww3_ufs1.1/work_${GRD}_${NP1}_${TAG}/*
+
+
+  echo "done running."
+
+  [[ -d ${path_build_root} ]] && rm -rf ${path_build_root}*
+  echo ' '
+  echo '     **************************************************************'
+  echo '     *  end of WAVEWATCH III         -             PDLIB regtest  *'
+  echo '     **************************************************************'
+  echo ' '