在R中使用黄土填充二维平面

I want to take noisy 2d data and use LOESS smoothing to find a smoother 2D surface. The data is the form of a data frame or matrix of r rows and c columns. The 'asbio' package will do surface plots for n*n data, and I can work out how to do 1D fits with 'loess' from the stats base package but I can't work out how to do the 2D plot.I want to take noisy 2d data and use LOESS smoo