Files
tensorneat-mend/tensorneat/algorithm/neat/genome/default.py
2024-06-16 21:47:53 +08:00

284 lines
9.7 KiB
Python

import warnings
from typing import Callable
import jax, jax.numpy as jnp
import sympy as sp
from utils import (
unflatten_conns,
topological_sort,
topological_sort_python,
I_INF,
extract_node_attrs,
extract_conn_attrs,
set_node_attrs,
set_conn_attrs,
attach_with_inf,
SYMPY_FUNCS_MODULE_NP,
SYMPY_FUNCS_MODULE_JNP,
)
from . import BaseGenome
from ..gene import BaseNodeGene, BaseConnGene, DefaultNodeGene, DefaultConnGene
from ..ga import BaseMutation, BaseCrossover, DefaultMutation, DefaultCrossover
class DefaultGenome(BaseGenome):
"""Default genome class, with the same behavior as the NEAT-Python"""
network_type = "feedforward"
def __init__(
self,
num_inputs: int,
num_outputs: int,
max_nodes=5,
max_conns=4,
node_gene: BaseNodeGene = DefaultNodeGene(),
conn_gene: BaseConnGene = DefaultConnGene(),
mutation: BaseMutation = DefaultMutation(),
crossover: BaseCrossover = DefaultCrossover(),
output_transform: Callable = None,
):
super().__init__(
num_inputs,
num_outputs,
max_nodes,
max_conns,
node_gene,
conn_gene,
mutation,
crossover,
)
if output_transform is not None:
try:
_ = output_transform(jnp.zeros(num_outputs))
except Exception as e:
raise ValueError(f"Output transform function failed: {e}")
self.output_transform = output_transform
def transform(self, state, nodes, conns):
u_conns = unflatten_conns(nodes, conns)
conn_exist = u_conns != I_INF
seqs = topological_sort(nodes, conn_exist)
return seqs, nodes, conns, u_conns
def restore(self, state, transformed):
seqs, nodes, conns, u_conns = transformed
return nodes, conns
def forward(self, state, transformed, inputs):
cal_seqs, nodes, conns, u_conns = transformed
ini_vals = jnp.full((self.max_nodes,), jnp.nan)
ini_vals = ini_vals.at[self.input_idx].set(inputs)
nodes_attrs = jax.vmap(extract_node_attrs)(nodes)
conns_attrs = jax.vmap(extract_conn_attrs)(conns)
def cond_fun(carry):
values, idx = carry
return (idx < self.max_nodes) & (cal_seqs[idx] != I_INF)
def body_func(carry):
values, idx = carry
i = cal_seqs[idx]
def input_node():
z = self.node_gene.input_transform(state, nodes_attrs[i], values[i])
new_values = values.at[i].set(z)
return new_values
def otherwise():
conn_indices = u_conns[:, i]
hit_attrs = attach_with_inf(conns_attrs, conn_indices)
ins = jax.vmap(self.conn_gene.forward, in_axes=(None, 0, 0))(
state, hit_attrs, values
)
z = self.node_gene.forward(
state,
nodes_attrs[i],
ins,
is_output_node=jnp.isin(i, self.output_idx),
)
new_values = values.at[i].set(z)
return new_values
values = jax.lax.cond(jnp.isin(i, self.input_idx), input_node, otherwise)
return values, idx + 1
vals, _ = jax.lax.while_loop(cond_fun, body_func, (ini_vals, 0))
if self.output_transform is None:
return vals[self.output_idx]
else:
return self.output_transform(vals[self.output_idx])
def update_by_batch(self, state, batch_input, transformed):
cal_seqs, nodes, conns, u_conns = transformed
batch_size = batch_input.shape[0]
batch_ini_vals = jnp.full((batch_size, self.max_nodes), jnp.nan)
batch_ini_vals = batch_ini_vals.at[:, self.input_idx].set(batch_input)
nodes_attrs = jax.vmap(extract_node_attrs)(nodes)
conns_attrs = jax.vmap(extract_conn_attrs)(conns)
def cond_fun(carry):
batch_values, nodes_attrs_, conns_attrs_, idx = carry
return (idx < self.max_nodes) & (cal_seqs[idx] != I_INF)
def body_func(carry):
batch_values, nodes_attrs_, conns_attrs_, idx = carry
i = cal_seqs[idx]
def input_node():
batch, new_attrs = self.node_gene.update_input_transform(
state, nodes_attrs_[i], batch_values[:, i]
)
return (
batch_values.at[:, i].set(batch),
nodes_attrs_.at[i].set(new_attrs),
conns_attrs_,
)
def otherwise():
conn_indices = u_conns[:, i]
hit_attrs = attach_with_inf(conns_attrs, conn_indices)
batch_ins, new_conn_attrs = jax.vmap(
self.conn_gene.update_by_batch,
in_axes=(None, 0, 1),
out_axes=(1, 0),
)(state, hit_attrs, batch_values)
batch_z, new_node_attrs = self.node_gene.update_by_batch(
state,
nodes_attrs_[i],
batch_ins,
is_output_node=jnp.isin(i, self.output_idx),
)
return (
batch_values.at[:, i].set(batch_z),
nodes_attrs_.at[i].set(new_node_attrs),
conns_attrs_.at[conn_indices].set(new_conn_attrs),
)
# the val of input nodes is obtained by the task, not by calculation
(batch_values, nodes_attrs_, conns_attrs_) = jax.lax.cond(
jnp.isin(i, self.input_idx),
input_node,
otherwise,
)
return batch_values, nodes_attrs_, conns_attrs_, idx + 1
batch_vals, nodes_attrs, conns_attrs, _ = jax.lax.while_loop(
cond_fun, body_func, (batch_ini_vals, nodes_attrs, conns_attrs, 0)
)
nodes = jax.vmap(set_node_attrs)(nodes, nodes_attrs)
conns = jax.vmap(set_conn_attrs)(conns, conns_attrs)
new_transformed = (cal_seqs, nodes, conns, u_conns)
if self.output_transform is None:
return batch_vals[:, self.output_idx], new_transformed
else:
return (
jax.vmap(self.output_transform)(batch_vals[:, self.output_idx]),
new_transformed,
)
def sympy_func(self, state, network, sympy_output_transform=None, backend="jax"):
assert backend in ["jax", "numpy"], "backend should be 'jax' or 'numpy'"
module = SYMPY_FUNCS_MODULE_JNP if backend == "jax" else SYMPY_FUNCS_MODULE_NP
if sympy_output_transform is None and self.output_transform is not None:
warnings.warn(
"genome.output_transform is not None but sympy_output_transform is None!"
)
input_idx = self.get_input_idx()
output_idx = self.get_output_idx()
order, _ = topological_sort_python(set(network["nodes"]), set(network["conns"]))
hidden_idx = [i for i in network["nodes"] if i not in input_idx and i not in output_idx]
symbols = {}
for i in network["nodes"]:
if i in input_idx:
symbols[i] = sp.Symbol(f"i{i - min(input_idx)}")
elif i in output_idx:
symbols[i] = sp.Symbol(f"o{i - min(output_idx)}")
else: # hidden
symbols[i] = sp.Symbol(f"h{i - min(hidden_idx)}")
nodes_exprs = {}
args_symbols = {}
for i in order:
if i in input_idx:
nodes_exprs[symbols[i]] = symbols[i]
else:
in_conns = [c for c in network["conns"] if c[1] == i]
node_inputs = []
for conn in in_conns:
val_represent = symbols[conn[0]]
# a_s -> args_symbols
val, a_s = self.conn_gene.sympy_func(
state,
network["conns"][conn],
val_represent,
)
args_symbols.update(a_s)
node_inputs.append(val)
nodes_exprs[symbols[i]], a_s = self.node_gene.sympy_func(
state,
network["nodes"][i],
node_inputs,
is_output_node=(i in output_idx),
)
args_symbols.update(a_s)
if i in output_idx and sympy_output_transform is not None:
nodes_exprs[symbols[i]] = sympy_output_transform(
nodes_exprs[symbols[i]]
)
input_symbols = [v for k, v in symbols.items() if k in input_idx]
reduced_exprs = nodes_exprs.copy()
for i in order:
reduced_exprs[symbols[i]] = reduced_exprs[symbols[i]].subs(reduced_exprs)
output_exprs = [reduced_exprs[symbols[i]] for i in output_idx]
lambdify_output_funcs = [
sp.lambdify(
input_symbols + list(args_symbols.keys()),
exprs,
modules=[backend, module],
)
for exprs in output_exprs
]
fixed_args_output_funcs = []
for i in range(len(output_idx)):
def f(inputs, i=i):
return lambdify_output_funcs[i](*inputs, *args_symbols.values())
fixed_args_output_funcs.append(f)
forward_func = lambda inputs: jnp.array([f(inputs) for f in fixed_args_output_funcs])
return (
symbols,
args_symbols,
input_symbols,
nodes_exprs,
output_exprs,
forward_func,
)