# How to plot 3d bar plot in Plotly Python

**URL:** <https://community.plotly.com/t/how-to-plot-3d-bar-plot-in-plotly-python/83565>\
**Category:** 📊 Plotly Python\
**Tags:** question\
**Created:** [April 3, 2024, 7:26pm UTC](https://community.plotly.com/t/how-to-plot-3d-bar-plot-in-plotly-python/83565 "2024-04-03T19:26:30Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Puspendu](https://avatars.discourse-cdn.com/v4/letter/p/76d3ee/32.png) [@Puspendu](https://community.plotly.com/u/Puspendu)\
**Post date:** [April 3, 2024, 7:26pm UTC](https://community.plotly.com/t/how-to-plot-3d-bar-plot-in-plotly-python/83565/1 "2024-04-03T19:26:30Z")

</div>

I have written a code that generates a 3D bar plot and a contour plot in Matplotlib, illustrating the distribution of a random walker’s position on a plane. However, I want to use Plotly for its interactive interface. Although I can plot the contour plot using `go.Histogram2dContour()`, I don’t know how to plot a 3D bar plot in Plotly.  
Can anyone help me with this?  
I’ve attached the code and the plot that I generated using Matplotlib.

```auto
import numpy as np
import matplotlib.pyplot as plt
from matplotlib import cm
from matplotlib.animation import FuncAnimation

stepsize = 0.5
num_steps = 200
num_trials = 10**3

final_position = []

for _ in range(num_trials):
    pos = np.array([0, 0])
    path = []
    for i in range(num_steps):
        pos = pos + np.random.normal(0, stepsize, 2)
        path.append(pos)
    final_position.append(np.array(path))
    
x = [final_position[i][:,0] for i in range(len(final_position))]
y = [final_position[j][:,1] for j in range(len(final_position))]
x_flattened = np.array(x).flatten()
y_flattened = np.array(y).flatten()

hist_fig = plt.figure(figsize=(14, 6), dpi = 200)

# 3D Histogram subplot
ax1 = hist_fig.add_subplot(121, projection='3d')
hist, xedges, yedges = np.histogram2d(x_flattened, y_flattened, bins=100)
xpos, ypos = np.meshgrid(xedges[:-1] + 0.25, yedges[:-1] + 0.25)
xpos = xpos.flatten('F')
ypos = ypos.flatten('F')
zpos = np.zeros_like(xpos)
dx = dy = 0.5 * np.ones_like(zpos)

dz = hist.flatten()
colors = plt.cm.magma(dz / dz.max())
ax1.bar3d(xpos, ypos, zpos, dx, dy, dz, color=colors, zsort='average')
ax1.set_xlabel('X')
ax1.set_ylabel('Y')
ax1.set_zlabel('Frequency')
ax1.set_title("Distribution of Walker's position on the xy plane")
cbar = plt.colorbar(cm.ScalarMappable(norm=plt.Normalize(dz.min(), dz.max()), cmap='magma'), ax=ax1, shrink=0.6, pad=0.12)

# Contour plot subplot
ax2 = hist_fig.add_subplot(122)
hist, xedges, yedges = np.histogram2d(x_flattened, y_flattened, bins=100)
xcenters = (xedges[:-1] + xedges[1:]) / 2
ycenters = (yedges[:-1] + yedges[1:]) / 2
X, Y = np.meshgrid(xcenters, ycenters)
contour = ax2.contourf(X, Y, hist.T, cmap='magma', levels = 25)
ax2.set_xlabel('X')
ax2.set_ylabel('Y')
ax2.set_xlim(min(xcenters), max(xcenters))
ax2.set_ylim(min(ycenters), max(ycenters))
ax2.set_title("Contour plot of the Walker's position on the xy plane")
ax2.set_aspect('equal')
cbar = plt.colorbar(contour, ax=ax2, shrink=0.6)

plt.show()

```

The plot will look like this

 ![image](https://us1.discourse-cdn.com/flex024/uploads/plot/original/3X/b/2/b201eaa9a007db09cb823c2919bde5230ea6cdd8.png)

---

<div class="post-metadata">

**Author:** ![AIMPED](https://sea2.discourse-cdn.com/flex024/user_avatar/community.plotly.com/aimped/32/21758_2.png) [@AIMPED](https://community.plotly.com/u/AIMPED)\
**Post date:** [April 3, 2024, 7:47pm UTC](https://community.plotly.com/t/how-to-plot-3d-bar-plot-in-plotly-python/83565/2 "2024-04-03T19:47:10Z")

</div>

Hey @Puspendu welcome to the forums.

Could you use a surface plot?

> **[3d](https://plotly.com/python/3d-surface-plots/)**
>
> Detailed examples of 3D Surface Plots including changing color, size, log axes, and more in Python.

As far as I know there are no built in 3d-bar plots. I answered this question a while ago, it seems pretty close to what you are after:

> [@Is it possible to make this with plotly?](https://community.plotly.com/t/is-it-possible-to-make-this-with-plotly/73696):
>