Overview Since the figure and add_subplot of matplotlib are magical in me, I will summarize them in an article to deepen my understanding.

The following import is assumed.

```
import matplotlib.pyplot as plt
```

Figure In matplotlib, the following magic is often described at the beginning.

```
fig = plt.figure()
```

`figure ()`

creates a Figure instance that reserves the entire drawing area. Image of preparing a large canvas or whiteboard.

It can be used without arguments, but the following arguments can be specified.

argument | processing |
---|---|

figsize | Specify drawing size in tuple format The unit is inches |

dpi | Specify the number of dots per inch |

facecolor | Specify background color |

edgecolor | Specify the border color The default border width is 0.0, so linewidth is required |

linewidth | Specify the border width |

Axes(add_subplot) I often see the following magic at the beginning.

```
fig = plt.figure()
ax = fig.add_subplot(1,1,1)
```

ʻAdd_subplot` creates a graph drawing area on the entire drawing area Figure. An image of pasting paper on a whiteboard and drawing a graph on the paper. The instance created at this time is a little complicated with the ** Axes ** class.

The relationship image between Figure and Axes (subplot) is as follows.

The argument of add_subplot is specified for the following purposes.

argument | processing |
---|---|

The first one | Specify the number of lines |

Second | Specify the number of columns |

Third | Specify the drawing location |

Divide the previously generated figure by the number of matrices specified in the first and second, and draw the graph in the place specified in the third.

For example, ʻadd_subplot (3,3,5) specifies the middle cell of the Figure divided by 3x3.

By the way, ʻadd_subplot (1,1,1)` is synonymous with ʻadd_subplot (111)`

.

Once you understand this, all you have to do is draw the graph on the Axes generated by ʻadd_subplot`.

```
fig = plt.figure()
ax = fig.add_subplot(111)
ax.hist([1, 2, 3])
fig.show()
```

It looks like this when drawing a rough graph with a stop of thinking.

Reference I refer to this article. Basics of matplotlib drawing-for those who don't understand figs and axes

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