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"""Static protocol for ``Path.from_evaluator_2nd``.
At runtime ``dim`` may be either a positive integer attribute or a
zero-argument method returning a positive integer. ``evaluate_q`` is
optional and may be implemented when position-only evaluation is cheaper
than computing all second-order derivatives.
"""
: |
"""Return ``(q, dq, ddq)`` for path parameters ``s``."""
...
"""Static protocol for ``Path.from_evaluator_3rd`` and ``from_evaluator``.
At runtime ``dim`` may be either a positive integer attribute or a
zero-argument method returning a positive integer. ``evaluate_q`` and
``evaluate_up_to_2nd`` are optional. If ``evaluate_up_to_2nd`` is omitted,
second-order evaluation falls back to ``evaluate_up_to_3rd`` and discards
``dddq``; this is supported for convenience but not recommended for
performance-sensitive code.
"""
: |
"""Return ``(q, dq, ddq, dddq)`` for path parameters ``s``."""
...
"""Configuration for waypoint-spline path construction.
The defaults build a quintic spline over ``s in [0, 1]`` with uniform
waypoint spacing, zero endpoint derivatives, and out-of-range errors.
Parameters
----------
order:
Odd spline order, at least 3. Common values are 3, 5, and 7.
s_min:
Lower endpoint of the path parameter range.
s_max:
Upper endpoint of the path parameter range. Must be greater than
``s_min`` when building a path.
out_of_range:
Evaluation policy outside ``[s_min, s_max]``. Strings are accepted for
script-friendly use; enum values are preferred for stable APIs.
parametrization:
Waypoint parameter assignment policy. Only uniform spacing is currently
supported.
start_state, end_state:
Optional ArrayLike matrices convertible to ``float64`` with shape
``(dim, (order - 1) // 2)``. Column ``r - 1`` stores the ``r``-th
derivative at the corresponding endpoint. ``None`` means zero endpoint
derivatives.
Raises
------
ValueError
If a wrapper-level option or boundary-state array format is invalid.
"""
:
:
:
:
:
: | None
: | None
...
"""Batch path-evaluation result.
Fields that were not requested by the evaluation method are ``None``.
Array shape follows the ``layout`` used when constructing the path:
- ``MatrixLayout.SAMPLE_MAJOR``: ``(n_samples, dim)``;
- ``MatrixLayout.DIM_MAJOR``: ``(dim, n_samples)``.
"""
:
: | None
: | None
: | None
"""Unified path object backed by the Rust COPP core."""
:
"""Number of path dimensions."""
:
"""Inclusive valid path-parameter range ``(s_min, s_max)``."""
"""Build a waypoint-spline path from an explicit ``SplineConfig``.
This overload mirrors the Rust API shape most closely: all spline
options are carried by ``config``, while ``layout`` only controls how
Python interprets the waypoint matrix and returned derivative arrays.
With the default ``MatrixLayout.SAMPLE_MAJOR``, ``waypoints`` has shape
``(n_points, dim)`` and each row is one waypoint. With
``MatrixLayout.DIM_MAJOR``, ``waypoints`` has shape ``(dim, n_points)``
and each column is one waypoint.
Parameters
----------
waypoints:
Two-dimensional ArrayLike value convertible to ``float64``.
config:
Spline construction options.
layout:
Matrix layout for both input waypoints and returned derivative
arrays. Strings ``"sample_major"`` and ``"dim_major"`` are
accepted.
Raises
------
ValueError
If array layout, dtype, or wrapper-level options are invalid.
CoppError
If the Rust COPP core rejects the path data or spline options.
"""
...
"""Build a waypoint-spline path.
With the default ``MatrixLayout.SAMPLE_MAJOR``, ``waypoints`` has shape
``(n_points, dim)`` and each row is one waypoint. With
``MatrixLayout.DIM_MAJOR``, ``waypoints`` has shape ``(dim, n_points)``
and each column is one waypoint.
Parameters
----------
waypoints:
Two-dimensional ArrayLike value convertible to ``float64``.
config:
Optional spline construction options. If omitted, keyword
arguments build an equivalent temporary ``SplineConfig``.
order, s_min, s_max, out_of_range, parametrization, start_state, end_state:
Spline construction options used only when ``config`` is omitted.
layout:
Matrix layout for both input waypoints and returned derivative
arrays. Strings ``"sample_major"`` and ``"dim_major"`` are
accepted.
Raises
------
ValueError
If array layout, dtype, wrapper-level options, or mixed
``config``/keyword options are invalid.
CoppError
If the Rust COPP core rejects the path data or spline options.
"""
...
"""Build a path from a scalar-parametric Python callable using JAX.
``from_jax`` is a high-level Python convenience constructor. It
differentiates ``q_fn(s)`` with JAX, wraps the generated derivatives as
a Python evaluator, and delegates to ``Path.from_evaluator_3rd``. The
Rust core still sees the same explicit ``(q, dq, ddq, dddq)`` evaluator
protocol.
Parameters
----------
q_fn:
Callable that receives one scalar path parameter and returns one
path vector. Use ``jax.numpy`` operations so JAX can trace it.
s_min, s_max:
Valid path-parameter range. Parametric paths currently match the
Rust evaluator API and reject out-of-range queries.
layout:
Matrix layout used for returned derivative arrays.
jit:
JIT-compile the JAX batched evaluator.
require_x64:
Require JAX 64-bit mode before construction.
Examples
--------
Enable x64 before constructing the path when using the default
``require_x64=True``::
import numpy as np
import jax
import jax.numpy as jnp
import copp_py as copp
jax.config.update("jax_enable_x64", True)
def q_fn(s):
return jnp.array([jnp.sin(s), jnp.cos(s), s + 0.1 * s**2])
path = copp.Path.from_jax(q_fn, 0.0, 1.0)
samples = np.array([0.0, 0.5, 1.0], dtype=np.float64)
out = path.evaluate_up_to_3rd(samples)
q = out.q
dq = out.dq
ddq = out.ddq
dddq = out.dddq
Raises
------
ImportError
If the selected optional dependency is missing. Install, for
example, with ``pip install "copp-py[jax]"``.
ValueError
If the JAX configuration or callback output shape is invalid.
CoppError
If the Rust COPP core rejects the path range or evaluator
dimension.
"""
...
"""Build a path from a scalar-parametric Python callable using Autograd.
This is the lightweight Python AD alternative to ``Path.from_jax``. It
differentiates ``q_fn(s)`` with Autograd, wraps the generated
derivatives as a Python evaluator, and delegates to
``Path.from_evaluator_3rd``.
Parameters
----------
q_fn:
Callable that receives one scalar path parameter and returns one
path vector. Use ``autograd.numpy`` operations so Autograd can
trace it.
s_min, s_max:
Valid path-parameter range. Autograd-backed paths currently match
the Rust evaluator API and reject out-of-range queries.
layout:
Matrix layout used for returned derivative arrays.
Examples
--------
The callable should use ``autograd.numpy`` rather than ordinary
``numpy`` so Autograd can trace scalar operations::
import numpy as np
import autograd.numpy as anp
import copp_py as copp
def q_fn(s):
return anp.array([anp.sin(s), anp.cos(s), s + 0.1 * s**2])
path = copp.Path.from_autograd(q_fn, 0.0, 1.0)
out = path.evaluate_up_to_3rd(
np.array([0.0, 0.5, 1.0], dtype=np.float64)
)
Raises
------
ImportError
If Autograd is missing. Install it with
``pip install "copp-py[autograd]"``.
ValueError
If the callback output shape is invalid.
CoppError
If the Rust COPP core rejects the path range or evaluator
dimension.
"""
...
"""Build a path from a scalar-parameter CasADi expression.
This constructor differentiates the CasADi expression in Python and
delegates the resulting explicit derivative evaluator to the Rust core.
Parameters
----------
q_expr:
CasADi ``SX``/``MX`` expression, vector expression, or sequence of
expressions describing ``q(s)``.
symbol:
Scalar CasADi ``SX`` or ``MX`` symbol used as the path parameter.
s_min, s_max:
Valid path-parameter range.
layout:
Matrix layout used for returned derivative arrays.
Examples
--------
Use a scalar ``SX`` or ``MX`` symbol as the path parameter, then pass a
vector expression for ``q(s)``::
import numpy as np
import casadi as ca
import copp_py as copp
s = ca.SX.sym("s")
q_expr = ca.vertcat(ca.sin(s), ca.cos(s), s + 0.1 * s**2)
path = copp.Path.from_casadi(
q_expr,
symbol=s,
s_min=0.0,
s_max=1.0,
)
out = path.evaluate_up_to_3rd(
np.array([0.0, 0.5, 1.0], dtype=np.float64)
)
Raises
------
ImportError
If CasADi is missing. Install it with
``pip install "copp-py[casadi]"``.
ValueError
If ``symbol`` is not scalar or ``q_expr`` is empty.
CoppError
If the Rust COPP core rejects the path range or evaluator
dimension.
"""
...
"""Build a path from scalar-parameter SymPy expressions.
SymPy expressions are differentiated symbolically and lambdified with
NumPy before the resulting evaluator is passed to the Rust core.
Parameters
----------
q_exprs:
A SymPy expression, sequence, or matrix describing ``q(s)``.
symbol:
Scalar SymPy symbol used as the path parameter.
s_min, s_max:
Valid path-parameter range.
layout:
Matrix layout used for returned derivative arrays.
Examples
--------
Pass a SymPy symbol and one expression per path dimension. Expressions
are differentiated symbolically and evaluated with NumPy::
import numpy as np
import sympy as sp
import copp_py as copp
s = sp.symbols("s")
q_exprs = [
sp.sin(s),
sp.cos(s),
s + sp.Rational(1, 10) * s**2,
]
path = copp.Path.from_sympy(
q_exprs,
symbol=s,
s_min=0.0,
s_max=1.0,
)
out = path.evaluate_up_to_3rd(
np.array([0.0, 0.5, 1.0], dtype=np.float64)
)
Raises
------
ImportError
If SymPy is missing. Install it with
``pip install "copp-py[sympy]"``.
ValueError
If ``q_exprs`` is empty or evaluates to an unexpected shape.
CoppError
If the Rust COPP core rejects the path range or evaluator
dimension.
"""
...
"""Build a path from a Python evaluator with derivatives up to second order.
The evaluator must provide ``dim`` and
``evaluate_up_to_2nd(s) -> (q, dq, ddq)``. ``evaluate_q(s) -> q`` is
optional and used when present. The callback receives ``s`` as a
one-dimensional contiguous ``float64`` array. Returned values may be
any ArrayLike convertible to two-dimensional ``float64`` arrays with
shape determined by ``layout``:
- ``MatrixLayout.SAMPLE_MAJOR``: ``(n_samples, dim)``;
- ``MatrixLayout.DIM_MAJOR``: ``(dim, n_samples)``.
Evaluator-backed paths currently match the Rust API and reject
out-of-range queries; no ``out_of_range`` option is exposed here.
Raises
------
ValueError
If the evaluator protocol or callback return arrays are invalid.
CoppError
If the Rust COPP core rejects the path range or evaluator
dimension.
Exception
Any exception raised by the Python evaluator callback is propagated
unchanged.
"""
...
"""Build a path from a Python evaluator with derivatives up to third order.
The evaluator must provide ``dim`` and
``evaluate_up_to_3rd(s) -> (q, dq, ddq, dddq)``. ``evaluate_q`` and
``evaluate_up_to_2nd`` are optional. If ``evaluate_up_to_2nd`` is
omitted, second-order evaluation calls ``evaluate_up_to_3rd`` and
discards ``dddq``; implement the lower-order callback too when this is
performance-sensitive.
Callback array layout and error behavior are the same as
``from_evaluator_2nd``.
"""
...
"""Compatibility alias for ``Path.from_evaluator_3rd``.
New code should prefer ``from_evaluator_2nd`` or
``from_evaluator_3rd`` so the supported derivative order is explicit.
"""
...
"""Evaluate position ``q`` only at path parameters ``s``.
``s`` may be any one-dimensional ArrayLike value convertible to
``float64``. The returned ``PathDerivatives`` has ``q`` populated and
derivative fields set to ``None``.
"""
...
"""Evaluate ``q``, ``dq``, and ``ddq`` at path parameters ``s``."""
...
"""Evaluate ``q``, ``dq``, ``ddq``, and ``dddq`` at path parameters ``s``."""
...