像您提供的那样， x_test 对于散点图没有意义.数组的大小实际上是不一样的:

print(x_test.shape)打印(y_test.shape)

(12，2)

(12,)

您可能想要的是这样的东西(仅使用 x_test 的第二列):

plt.scatter(x_test[:,1], y_test, color='black')plt.plot(x_test [:，1]，y_predict，color ='blue'，线宽= 3)

i have 2 arrays like this

x_test = [[ 14.   1.] [ 14.   2.] [ 14.   3.] [ 14.   4.] [ 14.   5.] [ 14.   6.] [ 14.   7.] [ 14.   8.] [ 14.   9.] [ 14.  10.] [ 14.  11.] [ 14.  12.]]

y_test = [ 254.7  255.4  476.5   19.5   85.6  352.   238.7  144.8   83.5  278.8   449.6  312.7]

i want these array to show scatter using matplotlib.

this is my code

plt.scatter(x_test, y_test,  color='black')
plt.plot(x_test, y_predict, color='blue', linewidth=3)

plt.xticks(())
plt.yticks(())

plt.show() 

and it gives me this error

Traceback (most recent call last):
  File "C:\wamp\www\python\test1.py", line 84, in <module>
    plt.scatter(x_test, y_test,  color='black')
  File "C:\Python34\lib\site-packages\matplotlib\pyplot.py", line 3251, in scatter
    edgecolors=edgecolors, data=data, **kwargs)
  File "C:\Python34\lib\site-packages\matplotlib\__init__.py", line 1812, in inner
    return func(ax, *args, **kwargs)
  File "C:\Python34\lib\site-packages\matplotlib\axes\_axes.py", line 3840, in scatter
    raise ValueError("x and y must be the same size")
ValueError: x and y must be the same size

both array length are same and i don't understand what is the problem here. please help me thanks

this is my y_predict array

y_predict = [  91.76428571  103.1          86.85714286  401.44642857  339.69642857
  196.83571429  126.38928571   31.41071429  211.67857143  167.35357143
  288.53214286  107.36785714]

The x_test, like you provided it, doesn't make sense for a scatter plot. And the arrays are actually not the same size:

print(x_test.shape)
print(y_test.shape)

(12, 2)

(12,)

What you might want to have instead is something like this (using only the second column of x_test):

plt.scatter(x_test[:,1], y_test,  color='black')
plt.plot(x_test[:,1], y_predict, color='blue', linewidth=3)