Files
PythonRobotics/Mapping/gaussian_grid_map/gaussian_grid_map.py
2019-12-14 21:33:26 +09:00

87 lines
2.3 KiB
Python

"""
2D gaussian grid map sample
author: Atsushi Sakai (@Atsushi_twi)
"""
import math
import numpy as np
import matplotlib.pyplot as plt
from scipy.stats import norm
EXTEND_AREA = 10.0 # [m] grid map extention length
show_animation = True
def generate_gaussian_grid_map(ox, oy, xyreso, std):
minx, miny, maxx, maxy, xw, yw = calc_grid_map_config(ox, oy, xyreso)
gmap = [[0.0 for i in range(yw)] for i in range(xw)]
for ix in range(xw):
for iy in range(yw):
x = ix * xyreso + minx
y = iy * xyreso + miny
# Search minimum distance
mindis = float("inf")
for (iox, ioy) in zip(ox, oy):
d = math.hypot(iox - x, ioy - y)
if mindis >= d:
mindis = d
pdf = (1.0 - norm.cdf(mindis, 0.0, std))
gmap[ix][iy] = pdf
return gmap, minx, maxx, miny, maxy
def calc_grid_map_config(ox, oy, xyreso):
minx = round(min(ox) - EXTEND_AREA / 2.0)
miny = round(min(oy) - EXTEND_AREA / 2.0)
maxx = round(max(ox) + EXTEND_AREA / 2.0)
maxy = round(max(oy) + EXTEND_AREA / 2.0)
xw = int(round((maxx - minx) / xyreso))
yw = int(round((maxy - miny) / xyreso))
return minx, miny, maxx, maxy, xw, yw
def draw_heatmap(data, minx, maxx, miny, maxy, xyreso):
x, y = np.mgrid[slice(minx - xyreso / 2.0, maxx + xyreso / 2.0, xyreso),
slice(miny - xyreso / 2.0, maxy + xyreso / 2.0, xyreso)]
plt.pcolor(x, y, data, vmax=1.0, cmap=plt.cm.Blues)
plt.axis("equal")
def main():
print(__file__ + " start!!")
xyreso = 0.5 # xy grid resolution
STD = 5.0 # standard diviation for gaussian distribution
for i in range(5):
ox = (np.random.rand(4) - 0.5) * 10.0
oy = (np.random.rand(4) - 0.5) * 10.0
gmap, minx, maxx, miny, maxy = generate_gaussian_grid_map(
ox, oy, xyreso, STD)
if show_animation: # pragma: no cover
plt.cla()
# for stopping simulation with the esc key.
plt.gcf().canvas.mpl_connect('key_release_event',
lambda event: [exit(0) if event.key == 'escape' else None])
draw_heatmap(gmap, minx, maxx, miny, maxy, xyreso)
plt.plot(ox, oy, "xr")
plt.plot(0.0, 0.0, "ob")
plt.pause(1.0)
if __name__ == '__main__':
main()