垂直線不尊重最小，最大極限（matplotlib）問題的

Question

最小工作示例：

import matplotlib.pyplot as plt 

horiz_line = 0.0005 
vert_line = 110 
x_data = [10, 30, 50, 70, 90, 110, 130, 150, 170, 190, 210, 230, 250, 270, 290, 310, 330, 350, 370, 390, 410, 430, 450, 470, 490] 
y_data = [0.0074999999999999997, 0.011875, 0.0057812499999999999, 0.0036458333333333334, 0.0020312500000000001, 0.0013125000000000001, 0.00098958333333333342, 0.00089285714285714283, 0.00074218750000000001, 0.00093749999999999997, 0.00071874999999999999, 0.00088068181818181821, 0.00078125000000000004, 0.0004807692307692308, 0.00055803571428571425, 0.00083333333333333339, 0.00066406250000000005, 0.00069852941176470592, 0.00059027777777777778, 0.00059210526315789478, 0.00062500000000000001, 0.0007291666666666667, 0.00068181818181818187, 0.00059782608695652171, 0.00053385416666666663] 

fig = plt.figure() # create the top-level container 

# horizontal line 
plt.axhline(y=horiz_line, xmin=0, xmax=max(x_data), color='red', zorder=1) 

# vertical line 
plt.axvline(x=vert_line, ymin=0, ymax=max(y_data), color='red', zorder=2) 

plt.scatter(x_data, y_data, s=150, color='blue', zorder=3) 

plt.show() 

，給了我這樣的：

通知小紅垂直線在x=110 。爲什麼它不符合我使用ymin=0, ymax=max(y_data)設置的最大限制（應該是min=0; max=0.011875）？

Answer 1

似乎要通過hlines和vlines，而不是axhline和axvline提供的功能，因爲這兩個後者使用Axes coordinate system，而hlines和vlines使用data coordinate system。

所以，你的代碼應該是

import matplotlib.pyplot as plt 

horiz_line = 0.0005 
vert_line = 110 
x_data = [10, 30, 50, 70, 90, 110, 130, 150, 170, 190, 210, 230, 250, 270, 290, 310, 330, 350, 370, 390, 410, 430, 450, 470, 490] 
y_data = [0.0074999999999999997, 0.011875, 0.0057812499999999999, 0.0036458333333333334, 0.0020312500000000001, 0.0013125000000000001, 0.00098958333333333342, 0.00089285714285714283, 0.00074218750000000001, 0.00093749999999999997, 0.00071874999999999999, 0.00088068181818181821, 0.00078125000000000004, 0.0004807692307692308, 0.00055803571428571425, 0.00083333333333333339, 0.00066406250000000005, 0.00069852941176470592, 0.00059027777777777778, 0.00059210526315789478, 0.00062500000000000001, 0.0007291666666666667, 0.00068181818181818187, 0.00059782608695652171, 0.00053385416666666663] 

fig = plt.figure() # create the top-level container 

# horizontal line 
plt.hlines(y=horiz_line, xmin=0, xmax=max(x_data), color='red', zorder=1) 

# vertical line 
plt.vlines(x=vert_line, ymin=0, ymax=max(y_data), color='red', zorder=2) 

plt.scatter(x_data, y_data, s=150, color='blue', zorder=3) 

plt.show()