昨天一位读者朋友问我`pyecharts`中，y轴如何显示在右侧。先说下如何设置，同时阐述例子君是如何找到找到此属性的。

这是pyecharts中一般的绘图步骤：

from pyecharts.faker import Faker

from pyecharts import options as opts

from pyecharts.charts import Bar

from pyecharts.commons.utils import JsCode

def bar_base() -> Bar:

c = (

Bar()

.add_xaxis(Faker.choose())

.add_yaxis("商家A", Faker.values())

.set_global_opts(title_opts=opts.TitleOpts(title="Bar-基本示例", subtitle="我是副标题"))

)

return c

bar_base().render('./bar.html')

那么，如何设置y轴显示在右侧，添加一行代码：

.set_global_opts(yaxis_opts=opts.AxisOpts(position='right'))

也就是：

c = (

Bar()

.add_xaxis(Faker.choose())

.add_yaxis("商家A", Faker.values())

.set_global_opts(title_opts=opts.TitleOpts(title="Bar-基本示例", subtitle="我是副标题"))

.set_global_opts(yaxis_opts=opts.AxisOpts(position='right'))

)

如何锁定这个属性，首先应该在set_global_opts函数的参数中找，它一共有以下`11`个设置参数，它们位于模块`charts.py`:

title_opts: types.Title = opts.TitleOpts(),

legend_opts: types.Legend = opts.LegendOpts(),

tooltip_opts: types.Tooltip = None,

toolbox_opts: types.Toolbox = None,

brush_opts: types.Brush = None,

xaxis_opts: types.Axis = None,

yaxis_opts: types.Axis = None,

visualmap_opts: types.VisualMap = None,

datazoom_opts: types.DataZoom = None,

graphic_opts: types.Graphic = None,

axispointer_opts: types.AxisPointer = None,

因为是设置y轴显示在右侧，自然想到设置参数`yaxis_opts`，因为其类型为`types.Axis`，所以再进入`types.py`，同时定位到`Axis`：

Axis = Union[opts.AxisOpts, dict, None]

Union是pyecharts中可容纳多个类型的并集列表，也就是Axis可能为`opts.AxisOpt`, `dict`, 或`None`三种类型。查看第一个`opts.AxisOpt`类，它共定义以下`25`个参数：

type_: Optional[str] = None,

name: Optional[str] = None,

is_show: bool = True,

is_scale: bool = False,

is_inverse: bool = False,

name_location: str = "end",

name_gap: Numeric = 15,

name_rotate: Optional[Numeric] = None,

interval: Optional[Numeric] = None,

grid_index: Numeric = 0,

position: Optional[str] = None,

offset: Numeric = 0,

split_number: Numeric = 5,

boundary_gap: Union[str, bool, None] = None,

min_: Union[Numeric, str, None] = None,

max_: Union[Numeric, str, None] = None,

min_interval: Numeric = 0,

max_interval: Optional[Numeric] = None,

axisline_opts: Union[AxisLineOpts, dict, None] = None,

axistick_opts: Union[AxisTickOpts, dict, None] = None,

axislabel_opts: Union[LabelOpts, dict, None] = None,

axispointer_opts: Union[AxisPointerOpts, dict, None] = None,

name_textstyle_opts: Union[TextStyleOpts, dict, None] = None,

splitarea_opts: Union[SplitAreaOpts, dict, None] = None,

splitline_opts: Union[SplitLineOpts, dict] = SplitLineOpts(),

观察后尝试参数`position`，结合官档：`https://pyecharts.org/#/zh-cn/global_options?id=axisopts%ef%bc%9a%e5%9d%90%e6%a0%87%e8%bd%b4%e9%85%8d%e7%bd%ae%e9%a1%b9`，介绍x轴设置position时有bottom, top, 所以y轴设置很可能就是left,right.

OK！