use libE_specs option, calc_dir_id_width

docs/data_structures/libE_specs.rst

@@ -81,6 +81,10 @@ the ``LibeSpecs`` class. When provided as a Python class, options are validated
                     Whether to allow overwrites and access to previous ensemble and workflow directories in subsequent runs.
                     ``False`` by default to protect results.
 
+                "calc_dir_id_width" [int] = ``4``:
+                    The width of the ID component of a calculation directory name. Up to this many additional
+                    zeros are padded to the sim/gen ID.
+
                 "use_worker_dirs" [bool] = ``False``:
                     Whether to organize calculation directories under worker-specific directories:
 

libensemble/libE.py

@@ -235,7 +235,6 @@ def libE(
     exit_criteria = ensemble.exit_criteria.dict(by_alias=True, exclude_none=True)
     alloc_specs = ensemble.alloc_specs.dict(by_alias=True)
     libE_specs = ensemble.libE_specs.dict(by_alias=True)
-    libE_specs["_exit_criteria"] = exit_criteria  # otherwise the workers don't have exit_criteria
 
     # Extract platform info from settings or environment
     platform_info = get_platform(libE_specs)

libensemble/specs.py

@@ -56,7 +56,7 @@ class SimSpecs(BaseModel):
     persis_in: Optional[List[str]] = []
     """
     List of field names that will be passed to a persistent simulation function
-    throughout runtime, following initialization
+    throughout runtime, following initialization.
     """
 
     # list of tuples for dtype construction
@@ -65,20 +65,20 @@ class SimSpecs(BaseModel):
     List of tuples corresponding to NumPy dtypes. e.g. ``("dim", int, (3,))``, or ``("path", str)``.
     Typically used to initialize an output array within the simulation function:
     ``out = np.zeros(100, dtype=sim_specs["out"])``.
-    Also used to construct the complete dtype for libEnsemble's history array
+    Also necessary to construct the complete dtype for libEnsemble's history array.
     """
 
     globus_compute_endpoint: Optional[str] = ""
     """
     A Globus Compute (https://www.globus.org/compute) ID corresponding to an active endpoint on a remote system.
     libEnsemble's workers will submit simulator function instances to this endpoint to be executed, instead of
-    calling them locally
+    calling them locally.
     """
 
     user: Optional[dict] = {}
     """
     A user-data dictionary to place bounds, constants, settings, or other parameters for customizing
-    the simulator function
+    the simulator function.
     """
 
     @validator("out", pre=True)
@@ -325,6 +325,12 @@ class LibeSpecs(BaseModel):
     If not using calculation directories, contents are copied to the ensemble directory
     """
 
+    calc_dir_id_width: Optional[int] = 4
+    """
+    The width of the ID component of a calculation directory name. Up to this many additional
+    zeros are padded to the sim/gen ID.
+    """
+
     platform: Optional[str] = ""
     """Name of a known platform defined in the platforms module.
 

libensemble/utils/output_directory.py

@@ -68,8 +68,7 @@ def __init__(self, libE_specs: dict, loc_stack: Optional[LocationStack] = None):
         if self.ensemble_copy_back:
             self.copybackdir = self.workflow_dir / Path(self.ensemble_dir.stem + "_back")
 
-        ec = self.specs.get("_exit_criteria", {})
-        self.pad = len(str(ec.get("sim_max", ""))) or len(str(ec.get("gen_max", "")))
+        self.pad = self.specs.get("calc_dir_id_width", 4)
 
     def make_copyback(self) -> None:
         """Check for existing ensemble dir and copybackdir, make copyback if doesn't exist"""