如何在Python中的函数指定的域中按比例绘制3?

时间:2018-12-16 20:15:26

标签: python matplotlib

因此,我尝试用matplotlib.pyplot绘制3维,但仅在其边界由函数设置的特定域中。这是代码

import numpy
from scipy.integrate import quad
import matplotlib.pyplot
import matplotlib.ticker
from mpl_toolkits.mplot3d import Axes3D

def get_x1min(pT, eta, rS):
    return (pT * numpy.exp(eta)) / (rS - pT * numpy.exp(- eta))

def get_x2(x1, pT, eta, rS):
    return (x1 * pT * numpy.exp(- eta)) / (x1 * rS - pT * numpy.exp(eta))

rS = 1960.0
eta = 0.0
pT = [66.0, 77.5, 89.5, 92.0, 94.0, 96.0, 98.0, 100.0, 103.0, 105.0, 107.0, 109.0, 111.0, 113.0, 118.5, 136.5, 157.5, 182.0, 200.0, 209.5, 241.5, 278.5, 321.0, 370.0, 426.5, 492.0]

fig = matplotlib.pyplot.figure()
ax = Axes3D(fig)
x1_test = numpy.linspace(0.1, 1.0, 20)
x1_test, pT = numpy.meshgrid(x1_test, pT)
x2_test = get_x2(x1_test, pT, eta, rS)
ax.plot_surface(x1_test, pT, x2_test, rstride=1, cstride=1, cmap=matplotlib.pyplot.get_cmap('rainbow'))
matplotlib.pyplot.show()

这很好用,但是域是一个矩形,唯一需要做的改变是使x1_test仅从可以从函数get_x1min获得的最小值开始。有什么方法吗?

谢谢!

1 个答案:

答案 0 :(得分:3)

您可以将不需要的值设置为np.nan,这样就不会绘制它们。请注意,虽然颜色映射似乎存在一些问题。您可以使用vminvmax关键字解决此问题:

mask = x1_test< get_x1min(pT, eta, rS)
x2_test[mask] = numpy.nan

ax.plot_surface(
    x1_test, pT, x2_test, rstride=1, cstride=1,
    cmap=matplotlib.pyplot.get_cmap('rainbow'),
    vmin = numpy.nanmin(x2_test),
    vmax = numpy.nanmax(x2_test),    
    )

matplotlib.pyplot.show()

其余代码将保持不变。结果看起来像这样:

result of the OP's code patched with the code posted above