极坐标系polar 配置center 参数时为什么传入 {x:30,y:30} 没有效果，并没有改变饼图中心位置，只能修改源码达到自己想要的情况

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---如题

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Start by reproducing the polar pie-chart configuration with center set to {x:30,y:30}, using the issue description as the available reproduction detail. Investigate why the center has no visible effect and consider the issue resolved when the documented configuration changes the pie-chart center without modifying library source.

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