文本属性及布局
译者：飞龙
matplotlib.text.Text实例有各种属性，可以通过关键字参数配置文本命令（例如，title()，xlabel()和text()）。
| 属性 | 值类型 |
|---|---|
| alpha | 浮点 |
| backgroundcolor | 任何 matplotlib 颜色 |
| bbox | rectangle prop dict plus key ‘pad’ which is a pad in points |
| clip_box | matplotlib.transform.Bbox 实例 |
| clip_on | [True / False] |
| clip_path | Path，Transform或Patch 实例 |
| color | 任何 matplotlib 颜色 |
| family | [ 'serif' / 'sans-serif' / 'cursive' / 'fantasy' / 'monospace' ] |
| fontproperties | matplotlib.font_manager.FontProperties 实例 |
| horizontalalignment or ha | [ 'center' / 'right' / 'left' ] |
| label | 任何字符串 |
| linespacing | 浮点 |
| multialignment | ['left' / 'right' / 'center' ] |
| name or fontname | 字符串，例如 ['Sans' / 'Courier' / 'Helvetica' ...] |
| picker | [None / 浮点 / 布尔值 / 可调用对象]` |
| position | (x,y) |
| rotation | [ 角度制的角度 / ‘vertical’ / ‘horizontal’ |
| size or fontsize | [ 点的尺寸 |
| style or fontstyle | [ 'normal' / 'italic' / 'oblique'] |
| text | 字符串或任何可使用'%s'打印的东西 |
| transform | matplotlib.transform 实例 |
| variant | [ 'normal' / 'small-caps' ] |
| verticalalignment or va | [ 'center' / 'top' / 'bottom' / 'baseline' ] |
| visible | [True / False] |
| weight or fontweight | [ 'normal' / 'bold' / 'heavy' / 'light' / 'ultrabold' / 'ultralight'] |
| x | 浮点 |
| y | 浮点 |
| zorder | 任意数值 |
你可以使用对齐参数horizontalalignment，verticalalignment和multialignment来布置文本。 horizontalalignment控制文本的x位置参数表示文本边界框的左边，中间或右边。 verticalalignment控制文本的y位置参数表示文本边界框的底部，中心或顶部。 multialignment，仅对于换行符分隔的字符串，控制不同的行是左，中还是右对齐。 这里是一个使用text()命令显示各种对齐方式的例子。 在整个代码中使用transform = ax.transAxes，表示坐标相对于轴边界框给出，其中0,0是轴的左下角，1,1是右上角。
import matplotlib.pyplot as plt
import matplotlib.patches as patches
# build a rectangle in axes coords
left, width = .25, .5
bottom, height = .25, .5
right = left + width
top = bottom + height
fig = plt.figure()
ax = fig.add_axes([0,0,1,1])
# axes coordinates are 0,0 is bottom left and 1,1 is upper right
p = patches.Rectangle(
(left, bottom), width, height,
fill=False, transform=ax.transAxes, clip_on=False
)
ax.add_patch(p)
ax.text(left, bottom, 'left top',
horizontalalignment='left',
verticalalignment='top',
transform=ax.transAxes)
ax.text(left, bottom, 'left bottom',
horizontalalignment='left',
verticalalignment='bottom',
transform=ax.transAxes)
ax.text(right, top, 'right bottom',
horizontalalignment='right',
verticalalignment='bottom',
transform=ax.transAxes)
ax.text(right, top, 'right top',
horizontalalignment='right',
verticalalignment='top',
transform=ax.transAxes)
ax.text(right, bottom, 'center top',
horizontalalignment='center',
verticalalignment='top',
transform=ax.transAxes)
ax.text(left, 0.5*(bottom+top), 'right center',
horizontalalignment='right',
verticalalignment='center',
rotation='vertical',
transform=ax.transAxes)
ax.text(left, 0.5*(bottom+top), 'left center',
horizontalalignment='left',
verticalalignment='center',
rotation='vertical',
transform=ax.transAxes)
ax.text(0.5*(left+right), 0.5*(bottom+top), 'middle',
horizontalalignment='center',
verticalalignment='center',
fontsize=20, color='red',
transform=ax.transAxes)
ax.text(right, 0.5*(bottom+top), 'centered',
horizontalalignment='center',
verticalalignment='center',
rotation='vertical',
transform=ax.transAxes)
ax.text(left, top, 'rotated\nwith newlines',
horizontalalignment='center',
verticalalignment='center',
rotation=45,
transform=ax.transAxes)
ax.set_axis_off()
plt.show()
