Question

新手matplotlib用户在这里。我正在尝试使用滑块来调整等高线图中的参数，但是当我这样做时，我得到：

AttributeError: QuadContourSet instance has no attribute 'set_data'

我怀疑我在错误的对象上调用set_data，但我找不到任何关于 right 对象的文档。你能帮我吗？感谢。

这是完整的代码：

import numpy as np
import matplotlib as mpl
import matplotlib.mlab as mlab
import matplotlib.pyplot as pyl
from matplotlib.contour import QuadContourSet
from matplotlib.widgets import Slider

#Define display parameters
mpl.rcParams['xtick.direction'] = 'out'
mpl.rcParams['ytick.direction'] = 'out'
delta = 0.025

#Define model parameters
alpha = .5
beta = .5
x_bar, a, b, c = 2, 0, 1, .1
v = np.arange(0, 10, delta)
w = np.arange(0, 10, delta)

#Calculate grid values
V, W = np.meshgrid(v,w)
Z = (V**(beta))*(W**(1-beta))
X = x_bar + a + b*Z
U = alpha*np.log(V) + (1-alpha)*np.log(X) - c*(W+V)

# Plot
fig = pyl.figure()

ax = fig.add_subplot(221)
CS = QuadContourSet(pyl.gca(), V, W, U, 200)
pyl.clabel(CS, inline=1, fontsize=10)
pyl.title('Simplest default with labels')

#Define slider for alpha
axcolor = 'lightgoldenrodyellow'
alpha_axis  = pyl.axes([0.25, 0.15, 0.65, 0.03], axisbg=axcolor)
alpha_slider = Slider(alpha_axis, 'Amp', 0, 1, valinit=.5)

def update(val):
    alpha = alpha_slider.val
    U = alpha*np.log(V) + (1-alpha)*np.log(X) - c*(W+V)
    CS.set_data(V, W, U)
    pyl.draw()

alpha_slider.on_changed(update)

pyl.show()

Answer 1

问题是QuadContourSet对象无法更新其数据，因为如果您任意更改数据，则需要重新计算整个数据。我不知道你的特定数据生成方式是否有一些可以简化修改轮廓线的方法，但如果没有，我认为你需要做的是从头开始绘制轮廓： / p>

# After your "Define model parameters" block

def compute_and_plot(ax, alpha):
    #Calculate grid values
    V, W = np.meshgrid(v,w)
    Z = (V**(beta))*(W**(1-beta))
    X = x_bar + a + b*Z
    U = alpha*np.log(V) + (1-alpha)*np.log(X) - c*(W+V)

    CS = QuadContourSet(ax, V, W, U, 200)
    pyl.clabel(CS, inline=1, fontsize=10)

# Plot
fig = pyl.figure()
pyl.title('Simplest default with labels')
ax = fig.add_subplot(221)
compute_and_plot(ax, alpha)

#Define slider for alpha
axcolor = 'lightgoldenrodyellow'
alpha_axis  = pyl.axes([0.25, 0.15, 0.65, 0.03], axisbg=axcolor)
alpha_slider = Slider(alpha_axis, 'Amp', 0, 1, valinit=.5)

def update(ax, val):
    alpha = alpha_slider.val
    ax.cla()
    compute_and_plot(ax, alpha)
    pyl.draw()

alpha_slider.on_changed(lambda val: update(ax, val))

pyl.show()

Matplotlib：带滑块小部件的等高线图

1 个答案: