gtsam/cython/test/test_OdometryExample.py

47 lines
1.7 KiB
Python

import unittest
from gtsam import *
from math import *
import numpy as np
class TestOdometryExample(unittest.TestCase):
def test_OdometryExample(self):
# Create the graph (defined in pose2SLAM.h, derived from
# NonlinearFactorGraph)
graph = NonlinearFactorGraph()
# Add a Gaussian prior on pose x_1
priorMean = Pose2(0.0, 0.0, 0.0) # prior mean is at origin
priorNoise = noiseModel_Diagonal.Sigmas(
np.array([0.3, 0.3, 0.1])) # 30cm std on x,y, 0.1 rad on theta
# add directly to graph
graph.add(PriorFactorPose2(1, priorMean, priorNoise))
# Add two odometry factors
# create a measurement for both factors (the same in this case)
odometry = Pose2(2.0, 0.0, 0.0)
odometryNoise = noiseModel_Diagonal.Sigmas(
np.array([0.2, 0.2, 0.1])) # 20cm std on x,y, 0.1 rad on theta
graph.add(BetweenFactorPose2(1, 2, odometry, odometryNoise))
graph.add(BetweenFactorPose2(2, 3, odometry, odometryNoise))
# Initialize to noisy points
initialEstimate = Values()
initialEstimate.insert(1, Pose2(0.5, 0.0, 0.2))
initialEstimate.insert(2, Pose2(2.3, 0.1, -0.2))
initialEstimate.insert(3, Pose2(4.1, 0.1, 0.1))
# Optimize using Levenberg-Marquardt optimization with an ordering from
# colamd
optimizer = LevenbergMarquardtOptimizer(graph, initialEstimate)
result = optimizer.optimizeSafely()
marginals = Marginals(graph, result)
marginals.marginalCovariance(1)
# Check first pose equality
pose_1 = result.atPose2(1)
self.assertTrue(pose_1.equals(Pose2(), 1e-4))
if __name__ == "__main__":
unittest.main()