Merge pull request #903 from borglab/feature/python-examples

release/4.3a0
Varun Agrawal 2021-10-23 01:06:09 -04:00 committed by GitHub
commit c56579c61d
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8 changed files with 481 additions and 400 deletions

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@ -9,15 +9,17 @@ CustomFactor demo that simulates a 1-D sensor fusion task.
Author: Fan Jiang, Frank Dellaert
"""
from functools import partial
from typing import List, Optional
import gtsam
import numpy as np
from typing import List, Optional
from functools import partial
I = np.eye(1)
def simulate_car():
# Simulate a car for one second
def simulate_car() -> List[float]:
"""Simulate a car for one second"""
x0 = 0
dt = 0.25 # 4 Hz, typical GPS
v = 144 * 1000 / 3600 # 144 km/hour = 90mph, pretty fast
@ -26,46 +28,9 @@ def simulate_car():
return x
x = simulate_car()
print(f"Simulated car trajectory: {x}")
# %%
add_noise = True # set this to False to run with "perfect" measurements
# GPS measurements
sigma_gps = 3.0 # assume GPS is +/- 3m
g = [x[k] + (np.random.normal(scale=sigma_gps) if add_noise else 0)
for k in range(5)]
# Odometry measurements
sigma_odo = 0.1 # assume Odometry is 10cm accurate at 4Hz
o = [x[k + 1] - x[k] + (np.random.normal(scale=sigma_odo) if add_noise else 0)
for k in range(4)]
# Landmark measurements:
sigma_lm = 1 # assume landmark measurement is accurate up to 1m
# Assume first landmark is at x=5, we measure it at time k=0
lm_0 = 5.0
z_0 = x[0] - lm_0 + (np.random.normal(scale=sigma_lm) if add_noise else 0)
# Assume other landmark is at x=28, we measure it at time k=3
lm_3 = 28.0
z_3 = x[3] - lm_3 + (np.random.normal(scale=sigma_lm) if add_noise else 0)
unknown = [gtsam.symbol('x', k) for k in range(5)]
print("unknowns = ", list(map(gtsam.DefaultKeyFormatter, unknown)))
# We now can use nonlinear factor graphs
factor_graph = gtsam.NonlinearFactorGraph()
# Add factors for GPS measurements
I = np.eye(1)
gps_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_gps)
def error_gps(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobians: Optional[List[np.ndarray]]):
def error_gps(measurement: np.ndarray, this: gtsam.CustomFactor,
values: gtsam.Values,
jacobians: Optional[List[np.ndarray]]) -> float:
"""GPS Factor error function
:param measurement: GPS measurement, to be filled with `partial`
:param this: gtsam.CustomFactor handle
@ -82,36 +47,9 @@ def error_gps(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobia
return error
# Add the GPS factors
for k in range(5):
gf = gtsam.CustomFactor(gps_model, [unknown[k]], partial(error_gps, np.array([g[k]])))
factor_graph.add(gf)
# New Values container
v = gtsam.Values()
# Add initial estimates to the Values container
for i in range(5):
v.insert(unknown[i], np.array([0.0]))
# Initialize optimizer
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
# Optimize the factor graph
result = optimizer.optimize()
# calculate the error from ground truth
error = np.array([(result.atVector(unknown[k]) - x[k])[0] for k in range(5)])
print("Result with only GPS")
print(result, np.round(error, 2), f"\nJ(X)={0.5 * np.sum(np.square(error))}")
# Adding odometry will improve things a lot
odo_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_odo)
def error_odom(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobians: Optional[List[np.ndarray]]):
def error_odom(measurement: np.ndarray, this: gtsam.CustomFactor,
values: gtsam.Values,
jacobians: Optional[List[np.ndarray]]) -> float:
"""Odometry Factor error function
:param measurement: Odometry measurement, to be filled with `partial`
:param this: gtsam.CustomFactor handle
@ -130,25 +68,9 @@ def error_odom(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobi
return error
for k in range(4):
odof = gtsam.CustomFactor(odo_model, [unknown[k], unknown[k + 1]], partial(error_odom, np.array([o[k]])))
factor_graph.add(odof)
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
result = optimizer.optimize()
error = np.array([(result.atVector(unknown[k]) - x[k])[0] for k in range(5)])
print("Result with GPS+Odometry")
print(result, np.round(error, 2), f"\nJ(X)={0.5 * np.sum(np.square(error))}")
# This is great, but GPS noise is still apparent, so now we add the two landmarks
lm_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_lm)
def error_lm(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobians: Optional[List[np.ndarray]]):
def error_lm(measurement: np.ndarray, this: gtsam.CustomFactor,
values: gtsam.Values,
jacobians: Optional[List[np.ndarray]]) -> float:
"""Landmark Factor error function
:param measurement: Landmark measurement, to be filled with `partial`
:param this: gtsam.CustomFactor handle
@ -165,15 +87,120 @@ def error_lm(measurement: np.ndarray, this: gtsam.CustomFactor, values, jacobian
return error
factor_graph.add(gtsam.CustomFactor(lm_model, [unknown[0]], partial(error_lm, np.array([lm_0 + z_0]))))
factor_graph.add(gtsam.CustomFactor(lm_model, [unknown[3]], partial(error_lm, np.array([lm_3 + z_3]))))
def main():
"""Main runner."""
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
x = simulate_car()
print(f"Simulated car trajectory: {x}")
result = optimizer.optimize()
add_noise = True # set this to False to run with "perfect" measurements
error = np.array([(result.atVector(unknown[k]) - x[k])[0] for k in range(5)])
# GPS measurements
sigma_gps = 3.0 # assume GPS is +/- 3m
g = [
x[k] + (np.random.normal(scale=sigma_gps) if add_noise else 0)
for k in range(5)
]
print("Result with GPS+Odometry+Landmark")
print(result, np.round(error, 2), f"\nJ(X)={0.5 * np.sum(np.square(error))}")
# Odometry measurements
sigma_odo = 0.1 # assume Odometry is 10cm accurate at 4Hz
o = [
x[k + 1] - x[k] +
(np.random.normal(scale=sigma_odo) if add_noise else 0)
for k in range(4)
]
# Landmark measurements:
sigma_lm = 1 # assume landmark measurement is accurate up to 1m
# Assume first landmark is at x=5, we measure it at time k=0
lm_0 = 5.0
z_0 = x[0] - lm_0 + (np.random.normal(scale=sigma_lm) if add_noise else 0)
# Assume other landmark is at x=28, we measure it at time k=3
lm_3 = 28.0
z_3 = x[3] - lm_3 + (np.random.normal(scale=sigma_lm) if add_noise else 0)
unknown = [gtsam.symbol('x', k) for k in range(5)]
print("unknowns = ", list(map(gtsam.DefaultKeyFormatter, unknown)))
# We now can use nonlinear factor graphs
factor_graph = gtsam.NonlinearFactorGraph()
# Add factors for GPS measurements
gps_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_gps)
# Add the GPS factors
for k in range(5):
gf = gtsam.CustomFactor(gps_model, [unknown[k]],
partial(error_gps, np.array([g[k]])))
factor_graph.add(gf)
# New Values container
v = gtsam.Values()
# Add initial estimates to the Values container
for i in range(5):
v.insert(unknown[i], np.array([0.0]))
# Initialize optimizer
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
# Optimize the factor graph
result = optimizer.optimize()
# calculate the error from ground truth
error = np.array([(result.atVector(unknown[k]) - x[k])[0]
for k in range(5)])
print("Result with only GPS")
print(result, np.round(error, 2),
f"\nJ(X)={0.5 * np.sum(np.square(error))}")
# Adding odometry will improve things a lot
odo_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_odo)
for k in range(4):
odof = gtsam.CustomFactor(odo_model, [unknown[k], unknown[k + 1]],
partial(error_odom, np.array([o[k]])))
factor_graph.add(odof)
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
result = optimizer.optimize()
error = np.array([(result.atVector(unknown[k]) - x[k])[0]
for k in range(5)])
print("Result with GPS+Odometry")
print(result, np.round(error, 2),
f"\nJ(X)={0.5 * np.sum(np.square(error))}")
# This is great, but GPS noise is still apparent, so now we add the two landmarks
lm_model = gtsam.noiseModel.Isotropic.Sigma(1, sigma_lm)
factor_graph.add(
gtsam.CustomFactor(lm_model, [unknown[0]],
partial(error_lm, np.array([lm_0 + z_0]))))
factor_graph.add(
gtsam.CustomFactor(lm_model, [unknown[3]],
partial(error_lm, np.array([lm_3 + z_3]))))
params = gtsam.GaussNewtonParams()
optimizer = gtsam.GaussNewtonOptimizer(factor_graph, v, params)
result = optimizer.optimize()
error = np.array([(result.atVector(unknown[k]) - x[k])[0]
for k in range(5)])
print("Result with GPS+Odometry+Landmark")
print(result, np.round(error, 2),
f"\nJ(X)={0.5 * np.sum(np.square(error))}")
if __name__ == "__main__":
main()

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@ -13,13 +13,8 @@ Author: Mandy Xie
from __future__ import print_function
import numpy as np
import gtsam
import matplotlib.pyplot as plt
import gtsam.utils.plot as gtsam_plot
# ENU Origin is where the plane was in hold next to runway
lat0 = 33.86998
lon0 = -84.30626
@ -29,28 +24,34 @@ h0 = 274
GPS_NOISE = gtsam.noiseModel.Isotropic.Sigma(3, 0.1)
PRIOR_NOISE = gtsam.noiseModel.Isotropic.Sigma(6, 0.25)
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Add a prior on the first point, setting it to the origin
# A prior factor consists of a mean and a noise model (covariance matrix)
priorMean = gtsam.Pose3() # prior at origin
graph.add(gtsam.PriorFactorPose3(1, priorMean, PRIOR_NOISE))
def main():
"""Main runner."""
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Add GPS factors
gps = gtsam.Point3(lat0, lon0, h0)
graph.add(gtsam.GPSFactor(1, gps, GPS_NOISE))
print("\nFactor Graph:\n{}".format(graph))
# Add a prior on the first point, setting it to the origin
# A prior factor consists of a mean and a noise model (covariance matrix)
priorMean = gtsam.Pose3() # prior at origin
graph.add(gtsam.PriorFactorPose3(1, priorMean, PRIOR_NOISE))
# Create the data structure to hold the initialEstimate estimate to the solution
# For illustrative purposes, these have been deliberately set to incorrect values
initial = gtsam.Values()
initial.insert(1, gtsam.Pose3())
print("\nInitial Estimate:\n{}".format(initial))
# Add GPS factors
gps = gtsam.Point3(lat0, lon0, h0)
graph.add(gtsam.GPSFactor(1, gps, GPS_NOISE))
print("\nFactor Graph:\n{}".format(graph))
# optimize using Levenberg-Marquardt optimization
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial, params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
# Create the data structure to hold the initialEstimate estimate to the solution
# For illustrative purposes, these have been deliberately set to incorrect values
initial = gtsam.Values()
initial.insert(1, gtsam.Pose3())
print("\nInitial Estimate:\n{}".format(initial))
# optimize using Levenberg-Marquardt optimization
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial, params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
if __name__ == "__main__":
main()

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@ -13,57 +13,60 @@ Author: Frank Dellaert
from __future__ import print_function
import numpy as np
import gtsam
import matplotlib.pyplot as plt
import gtsam.utils.plot as gtsam_plot
import matplotlib.pyplot as plt
import numpy as np
# Create noise models
ODOMETRY_NOISE = gtsam.noiseModel.Diagonal.Sigmas(np.array([0.2, 0.2, 0.1]))
PRIOR_NOISE = gtsam.noiseModel.Diagonal.Sigmas(np.array([0.3, 0.3, 0.1]))
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Add a prior on the first pose, setting it to the origin
# A prior factor consists of a mean and a noise model (covariance matrix)
priorMean = gtsam.Pose2(0.0, 0.0, 0.0) # prior at origin
graph.add(gtsam.PriorFactorPose2(1, priorMean, PRIOR_NOISE))
def main():
"""Main runner"""
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Add odometry factors
odometry = gtsam.Pose2(2.0, 0.0, 0.0)
# For simplicity, we will use the same noise model for each odometry factor
# Create odometry (Between) factors between consecutive poses
graph.add(gtsam.BetweenFactorPose2(1, 2, odometry, ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(2, 3, odometry, ODOMETRY_NOISE))
print("\nFactor Graph:\n{}".format(graph))
# Add a prior on the first pose, setting it to the origin
# A prior factor consists of a mean and a noise model (covariance matrix)
priorMean = gtsam.Pose2(0.0, 0.0, 0.0) # prior at origin
graph.add(gtsam.PriorFactorPose2(1, priorMean, PRIOR_NOISE))
# Create the data structure to hold the initialEstimate estimate to the solution
# For illustrative purposes, these have been deliberately set to incorrect values
initial = gtsam.Values()
initial.insert(1, gtsam.Pose2(0.5, 0.0, 0.2))
initial.insert(2, gtsam.Pose2(2.3, 0.1, -0.2))
initial.insert(3, gtsam.Pose2(4.1, 0.1, 0.1))
print("\nInitial Estimate:\n{}".format(initial))
# Add odometry factors
odometry = gtsam.Pose2(2.0, 0.0, 0.0)
# For simplicity, we will use the same noise model for each odometry factor
# Create odometry (Between) factors between consecutive poses
graph.add(gtsam.BetweenFactorPose2(1, 2, odometry, ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(2, 3, odometry, ODOMETRY_NOISE))
print("\nFactor Graph:\n{}".format(graph))
# optimize using Levenberg-Marquardt optimization
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial, params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
# Create the data structure to hold the initialEstimate estimate to the solution
# For illustrative purposes, these have been deliberately set to incorrect values
initial = gtsam.Values()
initial.insert(1, gtsam.Pose2(0.5, 0.0, 0.2))
initial.insert(2, gtsam.Pose2(2.3, 0.1, -0.2))
initial.insert(3, gtsam.Pose2(4.1, 0.1, 0.1))
print("\nInitial Estimate:\n{}".format(initial))
# 5. Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for i in range(1, 4):
print("X{} covariance:\n{}\n".format(i, marginals.marginalCovariance(i)))
fig = plt.figure(0)
for i in range(1, 4):
gtsam_plot.plot_pose2(0, result.atPose2(i), 0.5, marginals.marginalCovariance(i))
plt.axis('equal')
plt.show()
# optimize using Levenberg-Marquardt optimization
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial, params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
# 5. Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for i in range(1, 4):
print("X{} covariance:\n{}\n".format(i,
marginals.marginalCovariance(i)))
for i in range(1, 4):
gtsam_plot.plot_pose2(0, result.atPose2(i), 0.5,
marginals.marginalCovariance(i))
plt.axis('equal')
plt.show()
if __name__ == "__main__":
main()

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@ -13,69 +13,85 @@ Author: Alex Cunningham (C++), Kevin Deng & Frank Dellaert (Python)
from __future__ import print_function
import numpy as np
import gtsam
from gtsam.symbol_shorthand import X, L
import numpy as np
from gtsam.symbol_shorthand import L, X
# Create noise models
PRIOR_NOISE = gtsam.noiseModel.Diagonal.Sigmas(np.array([0.3, 0.3, 0.1]))
ODOMETRY_NOISE = gtsam.noiseModel.Diagonal.Sigmas(np.array([0.2, 0.2, 0.1]))
MEASUREMENT_NOISE = gtsam.noiseModel.Diagonal.Sigmas(np.array([0.1, 0.2]))
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Create the keys corresponding to unknown variables in the factor graph
X1 = X(1)
X2 = X(2)
X3 = X(3)
L1 = L(4)
L2 = L(5)
def main():
"""Main runner"""
# Add a prior on pose X1 at the origin. A prior factor consists of a mean and a noise model
graph.add(gtsam.PriorFactorPose2(X1, gtsam.Pose2(0.0, 0.0, 0.0), PRIOR_NOISE))
# Create an empty nonlinear factor graph
graph = gtsam.NonlinearFactorGraph()
# Add odometry factors between X1,X2 and X2,X3, respectively
graph.add(gtsam.BetweenFactorPose2(
X1, X2, gtsam.Pose2(2.0, 0.0, 0.0), ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(
X2, X3, gtsam.Pose2(2.0, 0.0, 0.0), ODOMETRY_NOISE))
# Create the keys corresponding to unknown variables in the factor graph
X1 = X(1)
X2 = X(2)
X3 = X(3)
L1 = L(4)
L2 = L(5)
# Add Range-Bearing measurements to two different landmarks L1 and L2
graph.add(gtsam.BearingRangeFactor2D(
X1, L1, gtsam.Rot2.fromDegrees(45), np.sqrt(4.0+4.0), MEASUREMENT_NOISE))
graph.add(gtsam.BearingRangeFactor2D(
X2, L1, gtsam.Rot2.fromDegrees(90), 2.0, MEASUREMENT_NOISE))
graph.add(gtsam.BearingRangeFactor2D(
X3, L2, gtsam.Rot2.fromDegrees(90), 2.0, MEASUREMENT_NOISE))
# Add a prior on pose X1 at the origin. A prior factor consists of a mean and a noise model
graph.add(
gtsam.PriorFactorPose2(X1, gtsam.Pose2(0.0, 0.0, 0.0), PRIOR_NOISE))
# Print graph
print("Factor Graph:\n{}".format(graph))
# Add odometry factors between X1,X2 and X2,X3, respectively
graph.add(
gtsam.BetweenFactorPose2(X1, X2, gtsam.Pose2(2.0, 0.0, 0.0),
ODOMETRY_NOISE))
graph.add(
gtsam.BetweenFactorPose2(X2, X3, gtsam.Pose2(2.0, 0.0, 0.0),
ODOMETRY_NOISE))
# Create (deliberately inaccurate) initial estimate
initial_estimate = gtsam.Values()
initial_estimate.insert(X1, gtsam.Pose2(-0.25, 0.20, 0.15))
initial_estimate.insert(X2, gtsam.Pose2(2.30, 0.10, -0.20))
initial_estimate.insert(X3, gtsam.Pose2(4.10, 0.10, 0.10))
initial_estimate.insert(L1, gtsam.Point2(1.80, 2.10))
initial_estimate.insert(L2, gtsam.Point2(4.10, 1.80))
# Add Range-Bearing measurements to two different landmarks L1 and L2
graph.add(
gtsam.BearingRangeFactor2D(X1, L1, gtsam.Rot2.fromDegrees(45),
np.sqrt(4.0 + 4.0), MEASUREMENT_NOISE))
graph.add(
gtsam.BearingRangeFactor2D(X2, L1, gtsam.Rot2.fromDegrees(90), 2.0,
MEASUREMENT_NOISE))
graph.add(
gtsam.BearingRangeFactor2D(X3, L2, gtsam.Rot2.fromDegrees(90), 2.0,
MEASUREMENT_NOISE))
# Print
print("Initial Estimate:\n{}".format(initial_estimate))
# Print graph
print("Factor Graph:\n{}".format(graph))
# Optimize using Levenberg-Marquardt optimization. The optimizer
# accepts an optional set of configuration parameters, controlling
# things like convergence criteria, the type of linear system solver
# to use, and the amount of information displayed during optimization.
# Here we will use the default set of parameters. See the
# documentation for the full set of parameters.
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial_estimate, params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
# Create (deliberately inaccurate) initial estimate
initial_estimate = gtsam.Values()
initial_estimate.insert(X1, gtsam.Pose2(-0.25, 0.20, 0.15))
initial_estimate.insert(X2, gtsam.Pose2(2.30, 0.10, -0.20))
initial_estimate.insert(X3, gtsam.Pose2(4.10, 0.10, 0.10))
initial_estimate.insert(L1, gtsam.Point2(1.80, 2.10))
initial_estimate.insert(L2, gtsam.Point2(4.10, 1.80))
# Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for (key, str) in [(X1, "X1"), (X2, "X2"), (X3, "X3"), (L1, "L1"), (L2, "L2")]:
print("{} covariance:\n{}\n".format(str, marginals.marginalCovariance(key)))
# Print
print("Initial Estimate:\n{}".format(initial_estimate))
# Optimize using Levenberg-Marquardt optimization. The optimizer
# accepts an optional set of configuration parameters, controlling
# things like convergence criteria, the type of linear system solver
# to use, and the amount of information displayed during optimization.
# Here we will use the default set of parameters. See the
# documentation for the full set of parameters.
params = gtsam.LevenbergMarquardtParams()
optimizer = gtsam.LevenbergMarquardtOptimizer(graph, initial_estimate,
params)
result = optimizer.optimize()
print("\nFinal Result:\n{}".format(result))
# Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for (key, s) in [(X1, "X1"), (X2, "X2"), (X3, "X3"), (L1, "L1"),
(L2, "L2")]:
print("{} covariance:\n{}\n".format(s,
marginals.marginalCovariance(key)))
if __name__ == "__main__":
main()

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@ -15,82 +15,88 @@ from __future__ import print_function
import math
import numpy as np
import gtsam
import matplotlib.pyplot as plt
import gtsam.utils.plot as gtsam_plot
import matplotlib.pyplot as plt
def vector3(x, y, z):
"""Create 3d double numpy array."""
return np.array([x, y, z], dtype=float)
def main():
"""Main runner."""
# Create noise models
PRIOR_NOISE = gtsam.noiseModel.Diagonal.Sigmas(gtsam.Point3(0.3, 0.3, 0.1))
ODOMETRY_NOISE = gtsam.noiseModel.Diagonal.Sigmas(
gtsam.Point3(0.2, 0.2, 0.1))
# Create noise models
PRIOR_NOISE = gtsam.noiseModel.Diagonal.Sigmas(vector3(0.3, 0.3, 0.1))
ODOMETRY_NOISE = gtsam.noiseModel.Diagonal.Sigmas(vector3(0.2, 0.2, 0.1))
# 1. Create a factor graph container and add factors to it
graph = gtsam.NonlinearFactorGraph()
# 1. Create a factor graph container and add factors to it
graph = gtsam.NonlinearFactorGraph()
# 2a. Add a prior on the first pose, setting it to the origin
# A prior factor consists of a mean and a noise ODOMETRY_NOISE (covariance matrix)
graph.add(gtsam.PriorFactorPose2(1, gtsam.Pose2(0, 0, 0), PRIOR_NOISE))
# 2a. Add a prior on the first pose, setting it to the origin
# A prior factor consists of a mean and a noise ODOMETRY_NOISE (covariance matrix)
graph.add(gtsam.PriorFactorPose2(1, gtsam.Pose2(0, 0, 0), PRIOR_NOISE))
# 2b. Add odometry factors
# Create odometry (Between) factors between consecutive poses
graph.add(
gtsam.BetweenFactorPose2(1, 2, gtsam.Pose2(2, 0, 0), ODOMETRY_NOISE))
graph.add(
gtsam.BetweenFactorPose2(2, 3, gtsam.Pose2(2, 0, math.pi / 2),
ODOMETRY_NOISE))
graph.add(
gtsam.BetweenFactorPose2(3, 4, gtsam.Pose2(2, 0, math.pi / 2),
ODOMETRY_NOISE))
graph.add(
gtsam.BetweenFactorPose2(4, 5, gtsam.Pose2(2, 0, math.pi / 2),
ODOMETRY_NOISE))
# 2b. Add odometry factors
# Create odometry (Between) factors between consecutive poses
graph.add(gtsam.BetweenFactorPose2(1, 2, gtsam.Pose2(2, 0, 0), ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(
2, 3, gtsam.Pose2(2, 0, math.pi / 2), ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(
3, 4, gtsam.Pose2(2, 0, math.pi / 2), ODOMETRY_NOISE))
graph.add(gtsam.BetweenFactorPose2(
4, 5, gtsam.Pose2(2, 0, math.pi / 2), ODOMETRY_NOISE))
# 2c. Add the loop closure constraint
# This factor encodes the fact that we have returned to the same pose. In real
# systems, these constraints may be identified in many ways, such as appearance-based
# techniques with camera images. We will use another Between Factor to enforce this constraint:
graph.add(
gtsam.BetweenFactorPose2(5, 2, gtsam.Pose2(2, 0, math.pi / 2),
ODOMETRY_NOISE))
print("\nFactor Graph:\n{}".format(graph)) # print
# 2c. Add the loop closure constraint
# This factor encodes the fact that we have returned to the same pose. In real
# systems, these constraints may be identified in many ways, such as appearance-based
# techniques with camera images. We will use another Between Factor to enforce this constraint:
graph.add(gtsam.BetweenFactorPose2(
5, 2, gtsam.Pose2(2, 0, math.pi / 2), ODOMETRY_NOISE))
print("\nFactor Graph:\n{}".format(graph)) # print
# 3. Create the data structure to hold the initial_estimate estimate to the
# solution. For illustrative purposes, these have been deliberately set to incorrect values
initial_estimate = gtsam.Values()
initial_estimate.insert(1, gtsam.Pose2(0.5, 0.0, 0.2))
initial_estimate.insert(2, gtsam.Pose2(2.3, 0.1, -0.2))
initial_estimate.insert(3, gtsam.Pose2(4.1, 0.1, math.pi / 2))
initial_estimate.insert(4, gtsam.Pose2(4.0, 2.0, math.pi))
initial_estimate.insert(5, gtsam.Pose2(2.1, 2.1, -math.pi / 2))
print("\nInitial Estimate:\n{}".format(initial_estimate)) # print
# 3. Create the data structure to hold the initial_estimate estimate to the
# solution. For illustrative purposes, these have been deliberately set to incorrect values
initial_estimate = gtsam.Values()
initial_estimate.insert(1, gtsam.Pose2(0.5, 0.0, 0.2))
initial_estimate.insert(2, gtsam.Pose2(2.3, 0.1, -0.2))
initial_estimate.insert(3, gtsam.Pose2(4.1, 0.1, math.pi / 2))
initial_estimate.insert(4, gtsam.Pose2(4.0, 2.0, math.pi))
initial_estimate.insert(5, gtsam.Pose2(2.1, 2.1, -math.pi / 2))
print("\nInitial Estimate:\n{}".format(initial_estimate)) # print
# 4. Optimize the initial values using a Gauss-Newton nonlinear optimizer
# The optimizer accepts an optional set of configuration parameters,
# controlling things like convergence criteria, the type of linear
# system solver to use, and the amount of information displayed during
# optimization. We will set a few parameters as a demonstration.
parameters = gtsam.GaussNewtonParams()
# 4. Optimize the initial values using a Gauss-Newton nonlinear optimizer
# The optimizer accepts an optional set of configuration parameters,
# controlling things like convergence criteria, the type of linear
# system solver to use, and the amount of information displayed during
# optimization. We will set a few parameters as a demonstration.
parameters = gtsam.GaussNewtonParams()
# Stop iterating once the change in error between steps is less than this value
parameters.setRelativeErrorTol(1e-5)
# Do not perform more than N iteration steps
parameters.setMaxIterations(100)
# Create the optimizer ...
optimizer = gtsam.GaussNewtonOptimizer(graph, initial_estimate, parameters)
# ... and optimize
result = optimizer.optimize()
print("Final Result:\n{}".format(result))
# Stop iterating once the change in error between steps is less than this value
parameters.setRelativeErrorTol(1e-5)
# Do not perform more than N iteration steps
parameters.setMaxIterations(100)
# Create the optimizer ...
optimizer = gtsam.GaussNewtonOptimizer(graph, initial_estimate, parameters)
# ... and optimize
result = optimizer.optimize()
print("Final Result:\n{}".format(result))
# 5. Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for i in range(1, 6):
print("X{} covariance:\n{}\n".format(i,
marginals.marginalCovariance(i)))
# 5. Calculate and print marginal covariances for all variables
marginals = gtsam.Marginals(graph, result)
for i in range(1, 6):
print("X{} covariance:\n{}\n".format(i, marginals.marginalCovariance(i)))
for i in range(1, 6):
gtsam_plot.plot_pose2(0, result.atPose2(i), 0.5,
marginals.marginalCovariance(i))
fig = plt.figure(0)
for i in range(1, 6):
gtsam_plot.plot_pose2(0, result.atPose2(i), 0.5, marginals.marginalCovariance(i))
plt.axis('equal')
plt.show()
plt.axis('equal')
plt.show()
if __name__ == "__main__":
main()

View File

@ -12,77 +12,86 @@ and does the optimization. Output is written on a file, in g2o format
# pylint: disable=invalid-name, E1101
from __future__ import print_function
import argparse
import math
import numpy as np
import matplotlib.pyplot as plt
import gtsam
import matplotlib.pyplot as plt
from gtsam.utils import plot
def vector3(x, y, z):
"""Create 3d double numpy array."""
return np.array([x, y, z], dtype=float)
def main():
"""Main runner."""
parser = argparse.ArgumentParser(
description="A 2D Pose SLAM example that reads input from g2o, "
"converts it to a factor graph and does the optimization. "
"Output is written on a file, in g2o format")
parser.add_argument('-i', '--input', help='input file g2o format')
parser.add_argument(
'-o',
'--output',
help="the path to the output file with optimized graph")
parser.add_argument('-m',
'--maxiter',
type=int,
help="maximum number of iterations for optimizer")
parser.add_argument('-k',
'--kernel',
choices=['none', 'huber', 'tukey'],
default="none",
help="Type of kernel used")
parser.add_argument("-p",
"--plot",
action="store_true",
help="Flag to plot results")
args = parser.parse_args()
g2oFile = gtsam.findExampleDataFile("noisyToyGraph.txt") if args.input is None\
else args.input
maxIterations = 100 if args.maxiter is None else args.maxiter
is3D = False
graph, initial = gtsam.readG2o(g2oFile, is3D)
assert args.kernel == "none", "Supplied kernel type is not yet implemented"
# Add prior on the pose having index (key) = 0
priorModel = gtsam.noiseModel.Diagonal.Variances(gtsam.Point3(1e-6, 1e-6, 1e-8))
graph.add(gtsam.PriorFactorPose2(0, gtsam.Pose2(), priorModel))
params = gtsam.GaussNewtonParams()
params.setVerbosity("Termination")
params.setMaxIterations(maxIterations)
# parameters.setRelativeErrorTol(1e-5)
# Create the optimizer ...
optimizer = gtsam.GaussNewtonOptimizer(graph, initial, params)
# ... and optimize
result = optimizer.optimize()
print("Optimization complete")
print("initial error = ", graph.error(initial))
print("final error = ", graph.error(result))
if args.output is None:
print("\nFactor Graph:\n{}".format(graph))
print("\nInitial Estimate:\n{}".format(initial))
print("Final Result:\n{}".format(result))
else:
outputFile = args.output
print("Writing results to file: ", outputFile)
graphNoKernel, _ = gtsam.readG2o(g2oFile, is3D)
gtsam.writeG2o(graphNoKernel, result, outputFile)
print("Done!")
if args.plot:
resultPoses = gtsam.utilities.extractPose2(result)
for i in range(resultPoses.shape[0]):
plot.plot_pose2(1, gtsam.Pose2(resultPoses[i, :]))
plt.show()
parser = argparse.ArgumentParser(
description="A 2D Pose SLAM example that reads input from g2o, "
"converts it to a factor graph and does the optimization. "
"Output is written on a file, in g2o format")
parser.add_argument('-i', '--input', help='input file g2o format')
parser.add_argument('-o', '--output',
help="the path to the output file with optimized graph")
parser.add_argument('-m', '--maxiter', type=int,
help="maximum number of iterations for optimizer")
parser.add_argument('-k', '--kernel', choices=['none', 'huber', 'tukey'],
default="none", help="Type of kernel used")
parser.add_argument("-p", "--plot", action="store_true",
help="Flag to plot results")
args = parser.parse_args()
g2oFile = gtsam.findExampleDataFile("noisyToyGraph.txt") if args.input is None\
else args.input
maxIterations = 100 if args.maxiter is None else args.maxiter
is3D = False
graph, initial = gtsam.readG2o(g2oFile, is3D)
assert args.kernel == "none", "Supplied kernel type is not yet implemented"
# Add prior on the pose having index (key) = 0
priorModel = gtsam.noiseModel.Diagonal.Variances(vector3(1e-6, 1e-6, 1e-8))
graph.add(gtsam.PriorFactorPose2(0, gtsam.Pose2(), priorModel))
params = gtsam.GaussNewtonParams()
params.setVerbosity("Termination")
params.setMaxIterations(maxIterations)
# parameters.setRelativeErrorTol(1e-5)
# Create the optimizer ...
optimizer = gtsam.GaussNewtonOptimizer(graph, initial, params)
# ... and optimize
result = optimizer.optimize()
print("Optimization complete")
print("initial error = ", graph.error(initial))
print("final error = ", graph.error(result))
if args.output is None:
print("\nFactor Graph:\n{}".format(graph))
print("\nInitial Estimate:\n{}".format(initial))
print("Final Result:\n{}".format(result))
else:
outputFile = args.output
print("Writing results to file: ", outputFile)
graphNoKernel, _ = gtsam.readG2o(g2oFile, is3D)
gtsam.writeG2o(graphNoKernel, result, outputFile)
print ("Done!")
if args.plot:
resultPoses = gtsam.utilities.extractPose2(result)
for i in range(resultPoses.shape[0]):
plot.plot_pose2(1, gtsam.Pose2(resultPoses[i, :]))
plt.show()
if __name__ == "__main__":
main()

View File

@ -8,13 +8,14 @@
# pylint: disable=invalid-name, E1101
from __future__ import print_function
import argparse
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
import gtsam
import matplotlib.pyplot as plt
import numpy as np
from gtsam.utils import plot
from mpl_toolkits.mplot3d import Axes3D
def vector6(x, y, z, a, b, c):
@ -22,50 +23,62 @@ def vector6(x, y, z, a, b, c):
return np.array([x, y, z, a, b, c], dtype=float)
parser = argparse.ArgumentParser(
description="A 3D Pose SLAM example that reads input from g2o, and "
"initializes Pose3")
parser.add_argument('-i', '--input', help='input file g2o format')
parser.add_argument('-o', '--output',
help="the path to the output file with optimized graph")
parser.add_argument("-p", "--plot", action="store_true",
help="Flag to plot results")
args = parser.parse_args()
def main():
"""Main runner."""
g2oFile = gtsam.findExampleDataFile("pose3example.txt") if args.input is None \
else args.input
parser = argparse.ArgumentParser(
description="A 3D Pose SLAM example that reads input from g2o, and "
"initializes Pose3")
parser.add_argument('-i', '--input', help='input file g2o format')
parser.add_argument(
'-o',
'--output',
help="the path to the output file with optimized graph")
parser.add_argument("-p",
"--plot",
action="store_true",
help="Flag to plot results")
args = parser.parse_args()
is3D = True
graph, initial = gtsam.readG2o(g2oFile, is3D)
g2oFile = gtsam.findExampleDataFile("pose3example.txt") if args.input is None \
else args.input
# Add Prior on the first key
priorModel = gtsam.noiseModel.Diagonal.Variances(vector6(1e-6, 1e-6, 1e-6,
1e-4, 1e-4, 1e-4))
is3D = True
graph, initial = gtsam.readG2o(g2oFile, is3D)
print("Adding prior to g2o file ")
firstKey = initial.keys()[0]
graph.add(gtsam.PriorFactorPose3(firstKey, gtsam.Pose3(), priorModel))
# Add Prior on the first key
priorModel = gtsam.noiseModel.Diagonal.Variances(
vector6(1e-6, 1e-6, 1e-6, 1e-4, 1e-4, 1e-4))
params = gtsam.GaussNewtonParams()
params.setVerbosity("Termination") # this will show info about stopping conds
optimizer = gtsam.GaussNewtonOptimizer(graph, initial, params)
result = optimizer.optimize()
print("Optimization complete")
print("Adding prior to g2o file ")
firstKey = initial.keys()[0]
graph.add(gtsam.PriorFactorPose3(firstKey, gtsam.Pose3(), priorModel))
print("initial error = ", graph.error(initial))
print("final error = ", graph.error(result))
params = gtsam.GaussNewtonParams()
params.setVerbosity(
"Termination") # this will show info about stopping conds
optimizer = gtsam.GaussNewtonOptimizer(graph, initial, params)
result = optimizer.optimize()
print("Optimization complete")
if args.output is None:
print("Final Result:\n{}".format(result))
else:
outputFile = args.output
print("Writing results to file: ", outputFile)
graphNoKernel, _ = gtsam.readG2o(g2oFile, is3D)
gtsam.writeG2o(graphNoKernel, result, outputFile)
print ("Done!")
print("initial error = ", graph.error(initial))
print("final error = ", graph.error(result))
if args.plot:
resultPoses = gtsam.utilities.allPose3s(result)
for i in range(resultPoses.size()):
plot.plot_pose3(1, resultPoses.atPose3(i))
plt.show()
if args.output is None:
print("Final Result:\n{}".format(result))
else:
outputFile = args.output
print("Writing results to file: ", outputFile)
graphNoKernel, _ = gtsam.readG2o(g2oFile, is3D)
gtsam.writeG2o(graphNoKernel, result, outputFile)
print("Done!")
if args.plot:
resultPoses = gtsam.utilities.allPose3s(result)
for i in range(resultPoses.size()):
plot.plot_pose3(1, resultPoses.atPose3(i))
plt.show()
if __name__ == "__main__":
main()

View File

@ -13,23 +13,29 @@ Author: Luca Carlone, Frank Dellaert (python port)
from __future__ import print_function
import gtsam
import numpy as np
import gtsam
# Read graph from file
g2oFile = gtsam.findExampleDataFile("pose3example.txt")
def main():
"""Main runner."""
# Read graph from file
g2oFile = gtsam.findExampleDataFile("pose3example.txt")
is3D = True
graph, initial = gtsam.readG2o(g2oFile, is3D)
is3D = True
graph, initial = gtsam.readG2o(g2oFile, is3D)
# Add prior on the first key. TODO: assumes first key ios z
priorModel = gtsam.noiseModel.Diagonal.Variances(
np.array([1e-6, 1e-6, 1e-6, 1e-4, 1e-4, 1e-4]))
firstKey = initial.keys()[0]
graph.add(gtsam.PriorFactorPose3(0, gtsam.Pose3(), priorModel))
# Add prior on the first key. TODO: assumes first key ios z
priorModel = gtsam.noiseModel.Diagonal.Variances(
np.array([1e-6, 1e-6, 1e-6, 1e-4, 1e-4, 1e-4]))
firstKey = initial.keys()[0]
graph.add(gtsam.PriorFactorPose3(0, gtsam.Pose3(), priorModel))
# Initializing Pose3 - chordal relaxation"
initialization = gtsam.InitializePose3.initialize(graph)
# Initializing Pose3 - chordal relaxation
initialization = gtsam.InitializePose3.initialize(graph)
print(initialization)
print(initialization)
if __name__ == "__main__":
main()