python之子图的索引如何工作

我有以下内容:

import matplotlib.pyplot as plt 
 
fig = plt.figure() 
 
for i in range(10): 
    ax = fig.add_subplot(551 + i) 
    ax.plot([1,2,3,4,5], [10,5,10,5,10], 'r-') 

我在想象 55 意味着它正在创建一个宽度为 5 个子图且深度为 5 个子图的网格 - 所以可以容纳 25 个子图吗？

for 循环只会迭代 10 次 - 所以我认为(显然是错误的)25 个可能的图可以容纳这些迭代，但我得到以下结果:

--------------------------------------------------------------------------- 
ValueError                                Traceback (most recent call last) 
<ipython-input-118-5775a5ea6c46> in <module>() 
     10  
     11 for i in range(10): 
---> 12     ax = fig.add_subplot(551 + i) 
     13     ax.plot([1,2,3,4,5], [10,5,10,5,10], 'r-') 
     14  
 
/home/blah/anaconda/lib/python2.7/site-packages/matplotlib/figure.pyc in add_subplot(self, *args, **kwargs) 
   1003                     self._axstack.remove(ax) 
   1004  
-> 1005             a = subplot_class_factory(projection_class)(self, *args, **kwargs) 
   1006  
   1007         self._axstack.add(key, a) 
 
/home/blah/anaconda/lib/python2.7/site-packages/matplotlib/axes/_subplots.pyc in __init__(self, fig, *args, **kwargs) 
     62                     raise ValueError( 
     63                         "num must be 1 <= num <= {maxn}, not {num}".format( 
---> 64                             maxn=rows*cols, num=num)) 
     65                 self._subplotspec = GridSpec(rows, cols)[int(num) - 1] 
     66                 # num - 1 for converting from MATLAB to python indexing 
 
ValueError: num must be 1 <= num <= 30, not 0 

请您参考如下方法:

在方便的速记符号中，55 表示有 5 行和 5 列。然而，速记符号仅适用于个位数整数(即 nrows、ncols 和 plot_number 均小于 10)。

您可以将其扩展为完整符号(即使用逗号:add_subplot(nrows, ncols, plot_number))然后一切都适合您:

for i in range(10): 
    ax = fig.add_subplot(5, 5, 1 + i) 
    ax.plot([1,2,3,4,5], [10,5,10,5,10], 'r-') 

来自 plt.subplot 的文档(它使用与 fig.add_subplot 相同的参数):

Typical call signature:

subplot(nrows, ncols, plot_number)  

Where nrows and ncols are used to notionally split the figure into nrows * ncols sub-axes, and plot_number is used to identify the particular subplot that this function is to create within the notional grid. plot_number starts at 1, increments across rows first and has a maximum of nrows * ncols.

In the case when nrows, ncols and plot_number are all less than 10, a convenience exists, such that the a 3 digit number can be given instead, where the hundreds represent nrows, the tens represent ncols and the units represent plot_number.