I am trying to use plotly
to plot the 3D convex-hull of a set of points. I am using Mesh3d
objects but the surfaces are not created correctly (see the picture below). How can I fix this?
import plotly.graph_objects as go
import itertools, math, numpy as np
from scipy.spatial import ConvexHull
# this simply creates a set of points
n = 3
m = 3
E = np.array(list(itertools.product(np.arange(-1, 1.1, .5), repeat=m)))
V = [
[-2.20676418, 1.53670924, -1.5541674 ],
[ 0.63437404, 0.07306301, 3.82253086],
[ 3.19989112, 0.71987311, 2.79373418]
]
x = np.array([np.dot(V, e) for e in E])
# then I compute the convex hull using scipy
xc = x[ConvexHull(x).vertices]
fig = go.Figure()
fig.add_trace(go.Mesh3d(x=xc[:, 0], y=xc[:, 1], z=xc[:, 2], color="blue", opacity=.5))
fig
Current output is:
I think what you miss is the alphahull option.
If you want a convex hull you need to add alphahull=0
:
import plotly.graph_objects as go
import itertools, math, numpy as np
from scipy.spatial import ConvexHull
# This simply creates a set of points:
n = 3
m = 3
E = np.array(list(itertools.product(np.arange(-1, 1.1, .5), repeat=m)))
V = [
[-2.20676418, 1.53670924, -1.5541674 ],
[ 0.63437404, 0.07306301, 3.82253086],
[ 3.19989112, 0.71987311, 2.79373418]
]
x = np.array([np.dot(V, e) for e in E])
# Then I compute the convex hull using scipy:
xc = x[ConvexHull(x).vertices]
fig = go.Figure()
fig.add_trace(go.Mesh3d(x=xc[:, 0],
y=xc[:, 1],
z=xc[:, 2],
color="blue",
opacity=.5,
alphahull=0))
fig
will give you the vube you want: