Renamed force_extras, and added outputs for force components

examples/features/committee_models/weighted_baseline/input.xml

@@ -43,8 +43,8 @@
     </initialize>
     <forces>
         <force forcefield='committee' nbeads='1'> 
-            <!-- adding these to force_extras will make the committee extras be treated properly with ring-polymer contraction, ect. -->
-            <force_extras> [committee_pot, committee_force, committee_virial, baseline_pot, baseline_force, baseline_virial, wb_mixing] </force_extras>
+            <!-- adding these to interpolate_extras will make the committee extras be treated properly with ring-polymer contraction, ect. -->
+            <interpolate_extras> [committee_pot, committee_force, committee_virial, baseline_pot, baseline_force, baseline_virial, wb_mixing] </interpolate_extras>
         </force>
     </forces>
     <motion mode='dynamics'>

examples/features/committee_models/weighted_baseline_extra/input.xml

@@ -40,8 +40,8 @@
     </initialize>
     <forces>
         <force forcefield='committee' nbeads='1'> 
-            <!-- adding these to force_extras will make the committee extras be treated properly with ring-polymer contraction, ect. -->
-            <force_extras> [committee_pot, committee_force, committee_virial, baseline_pot, baseline_force, baseline_virial, wb_mixing] </force_extras>
+            <!-- adding these to interpolate_extras will make the committee extras be treated properly with ring-polymer contraction, ect. -->
+            <interpolate_extras> [committee_pot, committee_force, committee_virial, baseline_pot, baseline_force, baseline_virial, wb_mixing] </interpolate_extras>
         </force>
     </forces>
     <motion mode='dynamics'>

examples/features/metadynamics/pimd_metadynamics_zundel/input.xml

@@ -36,7 +36,7 @@
          <temperature units="kelvin"> 300.0 </temperature>
          <bias>
            <force forcefield="plumed" nbeads="1">
-             <force_extras> [ doo, mtd.bias ] </force_extras>
+             <interpolate_extras> [ doo, mtd.bias ] </interpolate_extras>
            </force>
          </bias>
       </ensemble>

examples/features/path_integral_molecular_dynamics/pimd+mts_liquid_water/input.xml

@@ -1,7 +1,8 @@
 <simulation mode='md' verbosity='high'>
   <output prefix='simulation'>
-    <properties stride='1' filename='out'>  [ step, time{picosecond}, conserved, temperature{kelvin}, kinetic_cv, potential, pressure_cv{megapascal} ] </properties>
-    <trajectory filename='pos' stride='1'> positions </trajectory>
+    <properties stride='1' filename='out'>  [ step, time{picosecond}, conserved, temperature{kelvin}, kinetic_cv, potential, pressure_cv{megapascal}, pot_component_raw(0), pot_component_raw(1) ] </properties>
+    <trajectory filename='pos' stride='10'> positions </trajectory>
+    <trajectory filename='f-0c' stride='10'> forces_component_raw(0) </trajectory>
     <checkpoint stride='200'/>
   </output>
   <total_steps>100</total_steps>

examples/temp/pes/pswater/combine-extras/input.xml

@@ -39,10 +39,10 @@
     </initialize>
     <forces>
       <force forcefield='driver' weight="1.0">
-          <force_extras> ['dipole'] </force_extras>
+          <interpolate_extras> ['dipole'] </interpolate_extras>
       </force>
       <force forcefield='driver2' weight="2.0" >
-           <force_extras> ['dipole'] </force_extras>  
+           <interpolate_extras> ['dipole'] </interpolate_extras>  
       </force>
     </forces>
     <ensemble>

examples/temp/pes/pswater/contract-extras/input.xml

@@ -31,7 +31,7 @@
         <!-- The line below is the one that tells i-PI that the 'dipole' extras quantity will be 
         treated as a physical quantity like forces. It can then be interpolated, and if there are
         several force components, it will be automatically summed with the respective weights -->
-        <force_extras> [dipole] </force_extras>
+        <interpolate_extras> [dipole] </interpolate_extras>
       </force>
     </forces>
     <ensemble>

ipi/engine/forces.py

@@ -301,7 +301,7 @@ def __init__(
         weight=1.0,
         name="",
         mts_weights=None,
-        force_extras=None,
+        interpolate_extras=None,
         epsilon=-0.001,
     ):
         """Initializes ForceComponent
@@ -316,7 +316,7 @@ def __init__(
               will be weighted by this factor. The combination is a weighted sum.
            name: The name of the forcefield.
            mts_weights: Weight of forcefield at each mts level.
-           force_extras: A list of properties that should be treated as physical quantities,
+           interpolate_extras: A list of properties that should be treated as physical quantities,
               converted to numpy arrays and treated with ring polymer contraction. If
               different force components have this field, they will also be summed with
               the respective weight like a forces object.
@@ -330,10 +330,10 @@ def __init__(
             self.mts_weights = np.asarray([])
         else:
             self.mts_weights = np.asarray(mts_weights)
-        if force_extras is None:
-            self.force_extras = []
+        if interpolate_extras is None:
+            self.interpolate_extras = []
         else:
-            self.force_extras = force_extras
+            self.interpolate_extras = interpolate_extras
         self.epsilon = epsilon
 
     def bind(self, beads, cell, fflist, output_maker):
@@ -464,21 +464,21 @@ def extra_gather(self):
                     )
                 fc_extra[e].append(b.extra[e])
 
-        # force_extras should be numerical, thus can be converted to numpy arrays.
+        # interpolate_extras should be numerical, thus can be converted to numpy arrays.
         # we enforce the type and numpy will raise an error if not.
-        for e in self.force_extras:
+        for e in self.interpolate_extras:
             try:
                 fc_extra[e] = np.asarray(fc_extra[e], dtype=float)
             except KeyError:
                 raise KeyError(
-                    "force_extras required "
+                    "interpolate_extras required "
                     + e
                     + " to promote, but was not found among extras "
                     + str(list(fc_extra.keys()))
                 )
             except:
                 raise Exception(
-                    "force_extras has to be numerical to be treated as a physical quantity. It is not -- check the quantity that is being passed."
+                    "interpolate_extras has to be numerical to be treated as a physical quantity. It is not -- check the quantity that is being passed."
                 )
         return fc_extra
 
@@ -577,7 +577,7 @@ def __init__(self, baseforce, scaling=1):
         self._weight = depend_value(name="weight", value=0)
         dpipe(self.bf._weight, self._weight)
         self.mts_weights = self.bf.mts_weights
-        self.force_extras = self.bf.force_extras
+        self.interpolate_extras = self.bf.interpolate_extras
 
     def get_pots(self):
         return (
@@ -813,7 +813,7 @@ def make_rpc(rpc, beads):
                 nbeads=newb,
                 weight=fc.weight,
                 mts_weights=fc.mts_weights,
-                force_extras=fc.force_extras,
+                interpolate_extras=fc.interpolate_extras,
                 epsilon=fc.epsilon,
             )
             newbeads = Beads(beads.natoms, newb)
@@ -1450,8 +1450,8 @@ def extra_combine(self):
         for k in range(self.nforces):
             # combines the extras from the different force components
             for e, v in self.mforces[k].extras.items():
-                if e in self.mforces[k].force_extras:
-                    # extras that are tagged as force_extras are treated exactly as if they were an energy/force/stress
+                if e in self.mforces[k].interpolate_extras:
+                    # extras that are tagged as interpolate_extras are treated exactly as if they were an energy/force/stress
                     v = (
                         self.mforces[k].weight
                         * self.mforces[k].mts_weights.sum()

ipi/engine/properties.py

@@ -2833,6 +2833,36 @@ def __init__(self):
                     is printed verbatim. Will print out one file per bead, unless the bead attribute is set by the user.""",
                 "func": (lambda: self.system.forces.extras),
             },
+            "forces_component": {
+                "dimension": "force",
+                "help": """The contribution to the system forces from one of the force components.
+                       Takes one mandatory argument index (zero-based) that indicates which component of the
+                       potential must be returned. The optional argument 'bead' will print the potential associated
+                       with the specified bead, otherwise the centoid force is computed. 
+                       If the potential is weighed, the weight will be applied. """,
+                "func": lambda index, bead="-1": (
+                    self.system.forces.forces_component(int(index)).sum(axis=0)
+                    / self.system.beads.nbeads
+                    if int(bead) < 0
+                    else self.system.forces.forces_component(int(index))[int(bead)]
+                ),
+            },
+            "forces_component_raw": {
+                "dimension": "force",
+                "help": """The contribution to the system forces from one of the force components.
+                       Takes one mandatory argument index (zero-based) that indicates which component of the
+                       potential must be returned. The optional argument 'bead' will print the potential associated
+                       with the specified bead, otherwise the centoid force is computed. 
+                       If the potential is weighed, the weight will be applied. """,
+                "func": lambda index, bead="-1": (
+                    self.system.forces.forces_component(int(index), False).sum(axis=0)
+                    / self.system.beads.nbeads
+                    if int(bead) < 0
+                    else self.system.forces.forces_component(int(index), False)[
+                        int(bead)
+                    ]
+                ),
+            },
             "extras_component": {
                 "help": """The additional data returned by the client code, printed verbatim or expanded as a dictionary. See "extras". 
                            Fetches the extras from a specific force component, indicated in parentheses [extras_component(idx)]. """,

ipi/inputs/forces.py

@@ -79,7 +79,7 @@ class InputForceComponent(Input):
                 "dimension": "force",
             },
         ),
-        "force_extras": (
+        "interpolate_extras": (
             InputArray,
             {
                 "dtype": str,
@@ -107,7 +107,7 @@ def store(self, forceb):
         self.nbeads.store(forceb.nbeads)
         self.weight.store(forceb.weight)
         self.mts_weights.store(forceb.mts_weights)
-        self.force_extras.store(forceb.force_extras)
+        self.interpolate_extras.store(forceb.interpolate_extras)
         self.fd_epsilon.store(forceb.epsilon)
         self.name.store(forceb.name)
         self.forcefield.store(forceb.ffield)
@@ -126,7 +126,7 @@ def fetch(self):
             weight=self.weight.fetch(),
             name=self.name.fetch(),
             mts_weights=self.mts_weights.fetch(),
-            force_extras=self.force_extras.fetch(),
+            interpolate_extras=self.interpolate_extras.fetch(),
             epsilon=self.fd_epsilon.fetch(),
         )