Python中基于预生成二维表格的样条插值实现需求

我拥有包含X（Spd）、Y（Tq）、Z（Position）列的pandas DataFrame，已通过以下代码生成二维插值表格：

X = Reference_Data['Spd']
Y = Reference_Data['Tq']
X_Axis = np.linspace(500, 2200, 18)
Y_Axis = np.linspace(0, 2800, 29)
Z = Reference_Data['Position']
xi, yi = np.meshgrid(X_Axis, Y_Axis)
zi = griddata((X,Y),Z,(xi,yi),method='cubic')

现需针对如下多组Xi、Yi数值对，基于该二维表格实现样条插值，获取对应Z值：

内容的提问来源于stack exchange，提问作者Rajesh Patel