Wsrtjtyk

I am trying to 3d plot below data, with height being the respecitive joint probability from probability mass function. The idea is to visualize covariance. I had to go 3D because, the probabilities varies for different combinations of sample. The bars or boxes overlap each other in weird ways that I am unable to infer a proper 3d perspective in different angles. If you look at below gif you will know (box suddenly grows over each other at few angles out of nowhere). Kindly help how to resolve this issue. Also alpha is not working.

Issues:

1. Weird 3d boxes rendering

2. Alpha also not working

Problematic output:

MWE (jupyter):

%matplotlib inline

import matplotlib.pyplot as plt

import matplotlib.patches as patches

from itertools import product

from mpl_toolkits.mplot3d import Axes3D





X , Y = [100,250], [0,100,200]

xb, yb = 175, 125



import pandas as pd

matrix = np.array([

        [0.20, 0.10, 0.20],

        [0.05, 0.15, 0.30]

        ])

df = pd.DataFrame(matrix, columns=Y)

df.index = [100, 250]



top = 1

fig = plt.figure(figsize=(15,5))



ax1 = fig.add_subplot(121)



for xy in product(X,Y):

    x,y = xy[0], xy[1]

    z = df.loc[x,y]

    d1, d2 = xb - x, yb - y

    color = 'green' if d1*d2 > 0 else 'red'

    ax1.add_patch(patches.Rectangle((x, y), d1, d2, alpha=z, facecolor=color))

    ax1.scatter(x,y,color='black')





ax1.axvline(x=Xb, ls=':', color='blue')

ax1.axhline(y=Yb, ls=':', color='blue')

ax1.set_xticks(X)

ax1.set_yticks(Y)

ax1.set_xlim([min(X)-50,max(X)+50])

ax1.set_ylim([min(Y)-50,max(Y)+50])







ax2 = fig.add_subplot(122, projection='3d')

ax2.view_init(elev=30., azim=-50)

for xy in product(X,Y):    

    x ,y = xy[0], xy[1]

    z = df.loc[x,y]

#     print(x, y, z)

    width = x - 175

    depth = y - 125

    pro = width*depth

    top = z

    bottom = np.zeros_like(top)

    if pro > 0: #positive

        color='#B9F6CA'

    else:

        color='#EF9A9A'

    ax2.bar3d(x, y, bottom,  -width, -depth, top, color=color)

    ax2.scatter(x, y, z, color='blue')



def rotate(angle):

    ax2.view_init(azim=angle)    



from matplotlib import animation

ani = animation.FuncAnimation(fig, rotate, frames=np.arange(0,362,2),interval=100)    

from IPython.display import HTML

plt.close()

HTML(ani.to_jshtml())

Related math problem: