Add conditional time values

soil/environment.py

@@ -169,7 +169,7 @@ class BaseEnvironment(Model):
         Advance one step in the simulation, and update the data collection and scheduler appropriately
         """
         super().step()
-        self.logger.info(f"--- Step {self.now:^5} ---")
+        self.logger.info(f"--- Step: {self.schedule.steps:^5} - Time: {self.now:^5} ---")
         self.schedule.step()
         self.datacollector.collect(self)
 

soil/exporters.py

@@ -3,6 +3,7 @@ import sys
 from time import time as current_time
 from io import BytesIO
 from sqlalchemy import create_engine
+from textwrap import dedent, indent
 
 
 import matplotlib.pyplot as plt
@@ -86,6 +87,22 @@ class Exporter:
                 pass
         return open_or_reuse(f, mode=mode, **kwargs)
 
+    def get_dfs(self, env):
+        yield from get_dc_dfs(env.datacollector, trial_id=env.id)
+
+
+def get_dc_dfs(dc, trial_id=None):
+    dfs = {
+        "env": dc.get_model_vars_dataframe(),
+        "agents": dc.get_agent_vars_dataframe(),
+    }
+    for table_name in dc.tables:
+        dfs[table_name] = dc.get_table_dataframe(table_name)
+    if trial_id:
+        for (name, df) in dfs.items():
+            df["trial_id"] = trial_id
+    yield from dfs.items()
+
 
 class default(Exporter):
     """Default exporter. Writes sqlite results, as well as the simulation YAML"""
@@ -98,7 +115,7 @@ class default(Exporter):
         with self.output(self.simulation.name + ".dumped.yml") as f:
             f.write(self.simulation.to_yaml())
         self.dbpath = os.path.join(self.outdir, f"{self.simulation.name}.sqlite")
-        try_backup(self.dbpath, move=True)
+        try_backup(self.dbpath, remove=True)
 
     def trial_end(self, env):
         if self.dry_run:
@@ -111,24 +128,10 @@ class default(Exporter):
 
             engine = create_engine(f"sqlite:///{self.dbpath}", echo=False)
 
-            dc = env.datacollector
-            for (t, df) in get_dc_dfs(dc, trial_id=env.id):
+            for (t, df) in self.get_dfs(env):
                 df.to_sql(t, con=engine, if_exists="append")
 
 
-def get_dc_dfs(dc, trial_id=None):
-    dfs = {
-        "env": dc.get_model_vars_dataframe(),
-        "agents": dc.get_agent_vars_dataframe(),
-    }
-    for table_name in dc.tables:
-        dfs[table_name] = dc.get_table_dataframe(table_name)
-    if trial_id:
-        for (name, df) in dfs.items():
-            df["trial_id"] = trial_id
-    yield from dfs.items()
-
-
 class csv(Exporter):
 
     """Export the state of each environment (and its agents) in a separate CSV file"""
@@ -139,7 +142,7 @@ class csv(Exporter):
                 self.simulation.name, env.id, self.outdir
             )
         ):
-            for (df_name, df) in get_dc_dfs(env.datacollector, trial_id=env.id):
+            for (df_name, df) in self.get_dfs(env):
                 with self.output("{}.{}.csv".format(env.id, df_name)) as f:
                     df.to_csv(f)
 
@@ -192,52 +195,14 @@ class graphdrawing(Exporter):
             f.savefig(f)
 
 
-"""
-Convert an environment into a NetworkX graph
-"""
-
-
-def env_to_graph(env, history=None):
-    G = nx.Graph(env.G)
-
-    for agent in env.network_agents:
+class summary(Exporter):
+    """Print a summary of each trial to sys.stdout"""
 
-        attributes = {"agent": str(agent.__class__)}
-        lastattributes = {}
-        spells = []
-        lastvisible = False
-        laststep = None
-        if not history:
-            history = sorted(list(env.state_to_tuples()))
-        for _, t_step, attribute, value in history:
-            if attribute == "visible":
-                nowvisible = value
-                if nowvisible and not lastvisible:
-                    laststep = t_step
-                if not nowvisible and lastvisible:
-                    spells.append((laststep, t_step))
-
-                lastvisible = nowvisible
+    def trial_end(self, env):
+        for (t, df) in self.get_dfs(env):
+            if not len(df):
                 continue
-            key = "attr_" + attribute
-            if key not in attributes:
-                attributes[key] = list()
-            if key not in lastattributes:
-                lastattributes[key] = (value, t_step)
-            elif lastattributes[key][0] != value:
-                last_value, laststep = lastattributes[key]
-                commit_value = (last_value, laststep, t_step)
-                if key not in attributes:
-                    attributes[key] = list()
-                attributes[key].append(commit_value)
-                lastattributes[key] = (value, t_step)
-        for k, v in lastattributes.items():
-            attributes[k].append((v[0], v[1], None))
-        if lastvisible:
-            spells.append((laststep, None))
-        if spells:
-            G.add_node(agent.id, spells=spells, **attributes)
-        else:
-            G.add_node(agent.id, **attributes)
-
-    return G
+            msg = indent(str(df.describe()), '    ')
+            logger.info(dedent(f'''
+            Dataframe {t}:
+            ''') + msg)

soil/simulation.py

@@ -21,7 +21,6 @@ import pickle
 from . import serialization, exporters, utils, basestring, agents
 from .environment import Environment
 from .utils import logger, run_and_return_exceptions
-from .time import INFINITY
 from .config import Config, convert_old
 
 
@@ -194,7 +193,7 @@ class Simulation:
 
         # Set up agents on nodes
         def is_done():
-            return False
+            return not model.running
 
         if until and hasattr(model.schedule, "time"):
             prev = is_done
@@ -226,6 +225,9 @@ Model stats:
                 f'Simulation time {model.schedule.time}/{until}. Next: {getattr(model.schedule, "next_time", model.schedule.time + self.interval)}'
             )
             model.step()
+
+        if model.schedule.time < until:  # Simulation ended (no more steps) before until (i.e., no changes expected)
+            model.schedule.time = until
         return model
 
     def to_dict(self):

soil/time.py

@@ -2,6 +2,10 @@ from mesa.time import BaseScheduler
 from queue import Empty
 from heapq import heappush, heappop, heapify
 import math
+
+from inspect import getsource
+from numbers import Number
+
 from .utils import logger
 from mesa import Agent as MesaAgent
 
@@ -15,9 +19,55 @@ class When:
             return time
         self._time = time
 
-    def abs(self, time):
+    def next(self, time):
         return self._time
 
+    def abs(self, time):
+        return self
+
+    def __repr__(self):
+        return str(f"When({self._time})")
+
+    def __lt__(self, other):
+        if isinstance(other, Number):
+            return self._time < other
+        return self._time < other.next(self._time)
+
+    def __gt__(self, other):
+        if isinstance(other, Number):
+            return self._time > other
+        return self._time > other.next(self._time)
+
+    def ready(self, time):
+        return self._time <= time
+
+
+class Cond(When):
+    def __init__(self, func, delta=1):
+        self._func = func
+        self._delta = delta
+
+    def next(self, time):
+        return time + self._delta
+
+    def abs(self, time):
+        return self
+
+    def ready(self, time):
+        return self._func(time)
+
+    def __eq__(self, other):
+        return False
+
+    def __lt__(self, other):
+        return True
+
+    def __gt__(self, other):
+        return False
+
+    def __repr__(self):
+        return str(f'Cond("{getsource(self._func)}")')
+
 
 NEVER = When(INFINITY)
 
@@ -27,11 +77,19 @@ class Delta(When):
         self._delta = delta
 
     def __eq__(self, other):
-        return self._delta == other._delta
+        if isinstance(other, Delta):
+            return self._delta == other._delta
+        return False
 
     def abs(self, time):
+        return When(self._delta + time)
+
+    def next(self, time):
         return time + self._delta
 
+    def __repr__(self):
+        return str(f"Delta({self._delta})")
+
 
 class TimedActivation(BaseScheduler):
     """A scheduler which activates each agent when the agent requests.
@@ -47,14 +105,15 @@ class TimedActivation(BaseScheduler):
 
     def add(self, agent: MesaAgent, when=None):
         if when is None:
-            when = self.time
+            when = When(self.time)
+        elif not isinstance(when, When):
+            when = When(when)
         if agent.unique_id in self._agents:
-            self._queue.remove((self._next[agent.unique_id], agent.unique_id))
+            self._queue.remove((self._next[agent.unique_id], agent))
             del self._agents[agent.unique_id]
             heapify(self._queue)
 
-        heappush(self._queue, (when, agent.unique_id))
-        self._next[agent.unique_id] = when
+        heappush(self._queue, (when, agent))
         super().add(agent)
 
     def step(self) -> None:
@@ -63,42 +122,61 @@ class TimedActivation(BaseScheduler):
         an agent will signal when it wants to be scheduled next.
         """
 
-        self.logger.debug(f"Simulation step {self.next_time}")
+        self.logger.debug(f"Simulation step {self.time}")
         if not self.model.running:
             return
 
-        self.time = self.next_time
-        when = self.time
+        when = NEVER
+
+        to_process = []
+        skipped = []
+        next_time = INFINITY
 
-        while self._queue and self._queue[0][0] == self.time:
-            (when, agent_id) = heappop(self._queue)
-            self.logger.debug(f"Stepping agent {agent_id}")
+        ix = 0
 
-            agent = self._agents[agent_id]
-            returned = agent.step()
+        while self._queue:
+            (when, agent) = self._queue[0]
+            if when > self.time:
+                break
+            heappop(self._queue)
+            if when.ready(self.time):
+                to_process.append(agent)
+                continue
+
+            next_time = min(next_time, when.next(self.time))
+            self._next[agent.unique_id] = next_time
+            skipped.append((when, agent))
+
+        if self._queue:
+            next_time = min(next_time, self._queue[0][0].next(self.time))
+
+        self._queue = [*skipped, *self._queue]
+
+        for agent in to_process:
+            self.logger.debug(f"Stepping agent {agent}")
+
+            returned = ((agent.step() or Delta(1))).abs(self.time)
 
             if not getattr(agent, "alive", True):
                 self.remove(agent)
                 continue
 
-            when = (returned or Delta(1)).abs(self.time)
-            if when < self.time:
+            value = when.next(self.time)
+
+            if value < self.time:
                 raise Exception(
-                    "Cannot schedule an agent for a time in the past ({} < {})".format(
-                        when, self.time
-                    )
+                    f"Cannot schedule an agent for a time in the past ({when} < {self.time})"
                 )
+            if value < INFINITY:
+                next_time = min(value, next_time)
 
-            self._next[agent_id] = when
-            heappush(self._queue, (when, agent_id))
+                self._next[agent.unique_id] = returned
+                heappush(self._queue, (returned, agent))
 
         self.steps += 1
+        self.logger.debug(f"Updating time step: {self.time} -> {next_time}")
+        self.time = next_time
 
-        if not self._queue:
-            self.time = INFINITY
-            self.next_time = INFINITY
+        if not self._queue or next_time == INFINITY:
             self.model.running = False
             return self.time
-
-        self.next_time = self._queue[0][0]
-        self.logger.debug(f"Next step: {self.next_time}")

soil/utils.py

@@ -47,7 +47,7 @@ def timer(name="task", pre="", function=logger.info, to_object=None):
         to_object.end = end
 
 
-def try_backup(path, move=False):
+def try_backup(path, remove=False):
     if not os.path.exists(path):
         return None
     outdir = os.path.dirname(path)

tests/test_agents.py

@@ -18,7 +18,7 @@ class TestMain(TestCase):
         d = Dead(unique_id=0, model=environment.Environment())
         ret = d.step().abs(0)
         print(ret, "next")
-        assert ret == stime.INFINITY
+        assert ret == stime.NEVER
 
     def test_die_raises_exception(self):
         '''A dead agent should raise an exception if it is stepped after death'''

tests/test_exporters.py

@@ -50,7 +50,6 @@ class Exporters(TestCase):
 
         for env in s.run_simulation(exporters=[Dummy], dry_run=True):
             assert len(env.agents) == 1
-            assert env.now == max_time
 
         assert Dummy.started
         assert Dummy.ended