python-3.x - 'range'对象不支持python3中的项目分配

Question

如何解决这个错误:
在plot_rainbow中的第53行，文件“rainbow.py”
xr [0]，yr [0] = offset_curve(ax，x，y，lw/2。)
TypeError:“范围”对象不支持项目分配
在下面的代码中，好吗？我试图用xrange代替range，但这无济于事。

import numpy as np
import matplotlib.pyplot as plt

dpi = 100

def offset(x,y, o):
    """ Offset coordinates given by array x,y by o """
    X = np.c_[x,y].T
    m = np.array([[0,-1],[1,0]])
    R = np.zeros_like(X)
    S = X[:,2:]-X[:,:-2]
    R[:,1:-1] = np.dot(m, S)
    R[:,0] = np.dot(m, X[:,1]-X[:,0])
    R[:,-1] = np.dot(m, X[:,-1]-X[:,-2])
    On = R/np.sqrt(R[0,:]**2+R[1,:]**2)*o
    Out = On+X
    return Out[0,:], Out[1,:]


def offset_curve(ax, x,y, o):
    """ Offset array x,y in data coordinates
        by o in points """
    trans = ax.transData.transform
    inv = ax.transData.inverted().transform
    X = np.c_[x,y]
    Xt = trans(X)
    xto, yto = offset(Xt[:,0],Xt[:,1],o*dpi/72. )
    Xto = np.c_[xto, yto]
    Xo = inv(Xto)
    return Xo[:,0], Xo[:,1]


# some single points
y = np.array([1,2,2,3,3,0])    
x = np.arange(len(y))
#or try a sinus
x = np.linspace(0,9)
y=np.sin(x)*x/3.


fig, ax=plt.subplots(figsize=(4,2.5), dpi=dpi)

cols = ["#fff40b", "#00e103", "#ff9921", "#3a00ef", "#ff2121", "#af00e7"]
lw = 2.
lines = []
for i in range(len(cols)):
    l, = plt.plot(x,y, lw=lw, color=cols[i])
    lines.append(l)


def plot_rainbow(event=None):
    xr = range(6); yr = range(6); 
    xr[0],yr[0] = offset_curve(ax, x,y, lw/2.)
    xr[1],yr[1] = offset_curve(ax, x,y, -lw/2.)
    xr[2],yr[2] = offset_curve(ax, xr[0],yr[0], lw)
    xr[3],yr[3] = offset_curve(ax, xr[1],yr[1], -lw)
    xr[4],yr[4] = offset_curve(ax, xr[2],yr[2], lw)
    xr[5],yr[5] = offset_curve(ax, xr[3],yr[3], -lw)

    for i  in range(6):     
        lines[i].set_data(xr[i], yr[i])


plot_rainbow()

fig.canvas.mpl_connect("resize_event", plot_rainbow)
fig.canvas.mpl_connect("button_release_event", plot_rainbow)

plt.savefig(__file__+".png", dpi=dpi)
plt.show()

我尝试从this问题编译代码。

Answer 1

无法设置range对象。
您可以通过以下方式将其更改为列出:

 xr = list(range(6)); yr = list(range(6));  

但是我不明白为什么首先要在range中使用。如果您只是想初始化一个列表，我会选择类似的东西:

xr,  yr = 6*[None], 6*[None]

当然，您可以放入0或其他任何形式的None