Easy optimization!

.gitignore

@@ -1,5 +1,6 @@
 .idea/*
 tests/report*
 tests/asdf*
+tests/optim*
 tests/__pychache__/*
 trussme/__pycache__/*

tests/test_optimization.py

@@ -0,0 +1,124 @@
+import unittest
+import os
+
+import scipy.optimize
+import numpy
+
+import trussme
+
+
+class TestCustomStuff(unittest.TestCase):
+    def test_setup(self):
+        truss_from_commands = trussme.Truss()
+        truss_from_commands.add_pinned_joint([0.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([1.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([2.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([3.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([4.0, 0.0, 0.0])
+        truss_from_commands.add_pinned_joint([5.0, 0.0, 0.0])
+
+        truss_from_commands.add_free_joint([0.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([1.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([2.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([3.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([4.5, 1.0, 0.0])
+
+        truss_from_commands.add_out_of_plane_support("z")
+
+        truss_from_commands.joints[8].loads[1] = -20000
+
+        truss_from_commands.add_member(0, 1)
+        truss_from_commands.add_member(1, 2)
+        truss_from_commands.add_member(2, 3)
+        truss_from_commands.add_member(3, 4)
+        truss_from_commands.add_member(4, 5)
+
+        truss_from_commands.add_member(6, 7)
+        truss_from_commands.add_member(7, 8)
+        truss_from_commands.add_member(8, 9)
+        truss_from_commands.add_member(9, 10)
+
+        truss_from_commands.add_member(0, 6)
+        truss_from_commands.add_member(6, 1)
+        truss_from_commands.add_member(1, 7)
+        truss_from_commands.add_member(7, 2)
+        truss_from_commands.add_member(2, 8)
+        truss_from_commands.add_member(8, 3)
+        truss_from_commands.add_member(3, 9)
+        truss_from_commands.add_member(9, 4)
+        truss_from_commands.add_member(4, 10)
+        truss_from_commands.add_member(10, 5)
+
+        goals = trussme.Goals()
+
+        x0, obj, con, gen = trussme.make_optimization_functions(
+            truss_from_commands, goals
+        )
+
+        self.assertEqual(
+            trussme.report_to_str(gen(x0), goals),
+            trussme.report_to_str(truss_from_commands, goals),
+        )
+
+    def test_joint_optimization(self):
+        truss_from_commands = trussme.Truss()
+        truss_from_commands.add_pinned_joint([0.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([1.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([2.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([3.0, 0.0, 0.0])
+        truss_from_commands.add_free_joint([4.0, 0.0, 0.0])
+        truss_from_commands.add_pinned_joint([5.0, 0.0, 0.0])
+
+        truss_from_commands.add_free_joint([0.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([1.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([2.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([3.5, 1.0, 0.0])
+        truss_from_commands.add_free_joint([4.5, 1.0, 0.0])
+
+        truss_from_commands.add_out_of_plane_support("z")
+
+        truss_from_commands.joints[8].loads[1] = -20000
+
+        truss_from_commands.add_member(0, 1)
+        truss_from_commands.add_member(1, 2)
+        truss_from_commands.add_member(2, 3)
+        truss_from_commands.add_member(3, 4)
+        truss_from_commands.add_member(4, 5)
+
+        truss_from_commands.add_member(6, 7)
+        truss_from_commands.add_member(7, 8)
+        truss_from_commands.add_member(8, 9)
+        truss_from_commands.add_member(9, 10)
+
+        truss_from_commands.add_member(0, 6)
+        truss_from_commands.add_member(6, 1)
+        truss_from_commands.add_member(1, 7)
+        truss_from_commands.add_member(7, 2)
+        truss_from_commands.add_member(2, 8)
+        truss_from_commands.add_member(8, 3)
+        truss_from_commands.add_member(3, 9)
+        truss_from_commands.add_member(9, 4)
+        truss_from_commands.add_member(4, 10)
+        truss_from_commands.add_member(10, 5)
+
+        goals = trussme.Goals()
+
+        x0, obj, con, gen = trussme.make_optimization_functions(
+            truss_from_commands, goals, joint_coordinates=True, shape_parameters=False
+        )
+
+        results = scipy.optimize.minimize(
+            lambda x, *args: obj(x),
+            x0,
+            scipy.optimize.NonlinearConstraint(
+                con, -numpy.inf, 0.0, keep_feasible=True
+            ),
+            method="trust-constr",
+            options={"verbose": 2, "maxiter": 50},
+        )
+
+        result_truss = gen(results.x)
+        result_truss.analyze()
+        trussme.report_to_md(
+            os.path.join(os.path.dirname(__file__), "optim.md"), result_truss, goals
+        )

trussme/__init__.py

@@ -41,3 +41,4 @@
 )
 from trussme.truss import Truss, read_trs, read_json, Goals
 from trussme.report import report_to_str, report_to_md, print_report
+from trussme.optimize import make_truss_generator_function, make_optimization_functions

trussme/optimize.py

@@ -0,0 +1,163 @@
+from typing import Callable
+import io
+
+import numpy
+
+from trussme import Truss, Goals, read_json
+
+
+def make_x0(
+    truss: Truss,
+    joint_coordinates: bool = True,
+    shape_parameters: bool = True,
+) -> list[float]:
+    """
+    Returns a vector that encodes the current truss design
+
+    Parameters
+    ----------
+    truss: Truss
+        The truss to configure.
+    joint_coordinates: bool, default=True
+        Whether to include joint location parameters.
+    shape_parameters: bool, default=True
+        Whether to include shape parameters.
+
+    Returns
+    -------
+    list[float]
+        A starting vector that encodes the current truss design
+    """
+
+    planar_direction: str = truss.is_planar()
+    x0: list[float] = []
+
+    configured_truss = read_json(truss.to_json())
+
+    if joint_coordinates:
+        for i in range(len(configured_truss.joints)):
+            if (
+                numpy.sum(configured_truss.joints[i].translation_restricted)
+                == (0 if planar_direction == "none" else 1)
+                and numpy.sum(configured_truss.joints[i].loads) == 0
+            ):
+                if planar_direction != "x":
+                    x0.append(configured_truss.joints[i].coordinates[0])
+                if planar_direction != "y":
+                    x0.append(configured_truss.joints[i].coordinates[1])
+                if planar_direction != "z":
+                    x0.append(configured_truss.joints[i].coordinates[2])
+
+    return x0
+
+
+def make_truss_generator_function(
+    truss: Truss,
+    joint_coordinates: bool = True,
+    shape_parameters: bool = True,
+) -> Callable[[list[float]], Truss]:
+    """
+    Returns a function that takes a list of floats and returns a truss.
+
+    Parameters
+    ----------
+    truss: Truss
+        The truss to configure.
+    joint_coordinates: bool, default=True
+        Whether to include joint location parameters.
+    shape_parameters: bool, default=True
+        Whether to include shape parameters.
+
+    Returns
+    -------
+    Callable[[list[float]]
+        A tuple containing a vector that describes the input truss and a function that takes a list of floats and returns a truss.
+    """
+
+    planar_direction: str = truss.is_planar()
+
+    def truss_generator(x: list[float]) -> Truss:
+        configured_truss = read_json(truss.to_json())
+        idx = 0
+
+        if joint_coordinates:
+            for i in range(len(configured_truss.joints)):
+                if (
+                    numpy.sum(configured_truss.joints[i].translation_restricted)
+                    == (0 if planar_direction == "none" else 1)
+                    and numpy.sum(configured_truss.joints[i].loads) == 0
+                ):
+                    if planar_direction != "x":
+                        configured_truss.joints[i].coordinates[0] = x[idx]
+                        idx += 1
+                    if planar_direction != "y":
+                        configured_truss.joints[i].coordinates[1] = x[idx]
+                        idx += 1
+                    if planar_direction != "z":
+                        configured_truss.joints[i].coordinates[2] = x[idx]
+                        idx += 1
+
+        return configured_truss
+
+    return truss_generator
+
+
+def make_optimization_functions(
+    truss: Truss,
+    goals: Goals,
+    joint_coordinates: bool = True,
+    shape_parameters: bool = True,
+) -> tuple[
+    list[float],
+    Callable[[list[float]], float],
+    Callable[[list[float]], list[float]],
+    Callable[[list[float]], Truss],
+]:
+    """
+    Creates functions for use in optimization, including a starting vector, objective function, a constraint function, and a truss generator function.
+
+    Parameters
+    ----------
+    truss: Truss
+        The truss to use as a starting configuration
+    joint_coordinates: bool, default=True
+        Whether to include joint location parameters.
+    shape_parameters: bool, default=True
+        Whether to include shape parameters.
+
+    Returns
+    -------
+    tuple[
+        list[float],
+        Callable[[list[float]], float],
+        Callable[[list[float]], list[float]],
+        Callable[[list[float]], Truss],
+    ]
+        A tuple containing the starting vector, objective function, constraint function, and truss generator function.
+    """
+
+    x0 = make_x0(truss, joint_coordinates, shape_parameters)
+
+    truss_generator = make_truss_generator_function(
+        truss, joint_coordinates, shape_parameters
+    )
+
+    def objective_function(x: list[float]) -> float:
+        truss = truss_generator(x)
+        return truss.mass
+
+    def inequality_constraints(x: list[float]) -> list[float]:
+        truss = truss_generator(x)
+        truss.analyze()
+        return [
+            goals.minimum_fos_buckling - truss.fos_buckling,
+            goals.minimum_fos_yielding - truss.fos_yielding,
+            truss.deflection - goals.maximum_deflection,
+        ]
+
+    return (
+        x0,
+        objective_function,
+        inequality_constraints,
+        truss_generator,
+    )