如何使用Matplotlib在python中定义和绘制10 * 10数组？

Question

I am quite new to Python Matplot. I am trying to plot a 3d bar plot in which the hight of the bar is z and the position of the bars are x,y of my array.

This is an example of my data, I have an 10*10 array:

data = np.array([[0.1729,0.8658,0.9283,0.9381,0.9535,1.0000,1.0000,0.9999,0.9999,1.0000],
[-0.0430,0.3109,0.2788,0.5846,0.5369,0.5717,0.6357,0.5619,0.5866,0.6587],
[-0.2228,0.3427,0.1842,0.2106,0.4398,0.3896,0.4687,0.5749,0.4684,0.5484],
[0.0011,0.2899,0.1854,0.1040,0.3513,0.3863,0.3971,0.4485,0.2514,0.4946],
[-0.0096,0.0630,0.1564,-0.0077,0.0825,0.1637,0.2627,0.4800,0.3931,0.3244],
[0.0134,0.1198,0.3339,0.1243,-0.0864,0.4048,0.1996,0.3988,0.1970,0.5248],
[-0.0153,0.2806,0.1926,0.1918,0.0860,0.1054,0.3202,0.3063,0.2644,0.3791],
[-0.1118,0.3065,0.1396,0.0949,0.3459,0.1168,0.3730,0.0741,0.3518,0.2150],
[0.1022,0.3144,-0.1165,0.0509,0.1462,0.3265,0.2087,0.2549,0.3914,0.2683],
[-0.0083,-0.0228,0.0721,0.1086,0.2400,0.1899,0.0922,0.1006,0.2430,0.2768]])

I am using the below code to generate the 3d bar plot :

from mpl_toolkits.mplot3d import Axes3D
import matplotlib.pyplot as plt
import numpy as np

fig = plt.figure()
ax1 = Axes3D(fig)

xpos = np.arange(data.shape[0])
ypos = np.arange(data.shape[1])
zpos = data

xposM, yposM = np.meshgrid(xpos, ypos, copy=False)

dx=0.5
dy=0.5
dz=zpos

ax1.bar3d(xposM.ravel(), yposM.ravel(), dz, dx, dy, dz)
plt.show()

but I am getting this error:

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

Does any body know what is the problem of my code?

Answer 1

There are two issues with your code.

1: zpos should not be =data ; this is the main hangup you are having.

2: You should (probably) be calling bar3d as ax1.bar3d(xposM.ravel(), yposM.ravel(), zpos, dx, dy, dz) . As it stands, you are positioning your bars to have their base at where they should go. That is, a bar of height 3 is going to start at z=3 and go to z=6, and a bar of height -2.1 is going to start at z=-2.1.

As for the first issue, xpos and ypos have shape (100,), while data has shape (10,10). You need them to have the same dimensions, so I would recommend including zpos = np.zeros(len(data.ravel())) . This also means you will need to set dz = data.ravel() .