我正在嘗試繪制具有非結構化坐標的 2D 資料matplotlib集tricontourf。我可以用 生成“網格”圖triplot，但是當我使用相同的Triangulation物件時tricontourf，我得到一個錯誤（見下文）。我錯過了什么？例子：
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import numpy as np
import matplotlib as mpl
import matplotlib.pyplot as plt
def lower(x):
return 2 1*x
def upper(x):
return 60 4*x
ni = 10
nj = 12
x = np.linspace(1,15,ni)
## make a trapezoid
xy = np.zeros((ni,nj,2),dtype=np.float32)
for i in range(len(x)):
y = np.linspace(lower(x[i]),upper(x[i]),nj)
xy[i,:,0] = x[i]
xy[i,:,1] = y
## add noise
xy = -0.1 0.2*np.random.rand(ni,nj,2)
## make tris 'indices list'
xi, yi = np.meshgrid(range(ni), range(nj), indexing='xy')
inds_list = np.stack((xi,yi), axis=2)
inds_list = np.reshape(inds_list, (ni*nj,2), order='C')
inds_list = np.ravel_multi_index((inds_list[:,0],inds_list[:,1]), (ni,nj), order='C')
inds_list = np.reshape(inds_list, (ni,nj), order='F')
tris = np.zeros((2*(ni-1)*(nj-1),3), dtype=np.int64)
ci=0
for i in range(ni-1):
for j in range(nj-1):
tris[ci,0] = inds_list[i 1, j 1]
tris[ci,1] = inds_list[i, j 1]
tris[ci,2] = inds_list[i, j ]
ci =1
tris[ci,0] = inds_list[i, j ]
tris[ci,1] = inds_list[i 1, j ]
tris[ci,2] = inds_list[i 1, j 1]
ci =1
triangulation = mpl.tri.Triangulation(x=xy[:,:,0].ravel(), y=xy[:,:,1].ravel(), triangles=tris)
fig1 = plt.figure(figsize=(4, 4/(16/9)), dpi=300)
ax1 = plt.gca()
ax1.triplot(triangulation, lw=0.5)
#ax1.tricontourf(triangulation)
fig1.tight_layout(pad=0.25)
plt.show()
...產生
但是，取消注釋該行ax1.tricontourf
拋出錯誤：
Traceback (most recent call last):
File "test.py", line 54, in <module>
ax1.tricontourf(triangulation)
File "C:\Users\steve\AppData\Roaming\Python\Python38\site-packages\matplotlib\tri\tricontour.py", line 307, in tricontourf
return TriContourSet(ax, *args, **kwargs)
File "C:\Users\steve\AppData\Roaming\Python\Python38\site-packages\matplotlib\tri\tricontour.py", line 29, in __init__
super().__init__(ax, *args, **kwargs)
File "C:\Users\steve\AppData\Roaming\Python\Python38\site-packages\matplotlib\contour.py", line 812, in __init__
kwargs = self._process_args(*args, **kwargs)
File "C:\Users\steve\AppData\Roaming\Python\Python38\site-packages\matplotlib\tri\tricontour.py", line 45, in _process_args
tri, z = self._contour_args(args, kwargs)
File "C:\Users\steve\AppData\Roaming\Python\Python38\site-packages\matplotlib\tri\tricontour.py", line 60, in _contour_args
z = np.ma.asarray(args[0])
IndexError: list index out of range
我在用：
Python版本：3.8.9
matplotlib 版本：3.5.1
uj5u.com熱心網友回復：
我會說您需要為輪廓提供值陣列，例如：
x= xy[:,:,0].ravel()
z= np.random.rand(x.shape[0])
ax1.tricontourf(triangulation, z)
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標籤：Python 麻木的 matplotlib