如何在GGally中使用ggpairs绘制黄土估计值？

Question

我尝试了一下GGally包。尤其是ggpairs函数。然而，我想不出如何在平滑的情况下使用lm而不是loess。有什么想法吗？下面是我的代码：

require(GGally)
diamonds.samp <- diamonds[sample(1:dim(diamonds)[1],200),]
ggpairs(diamonds.samp[,c(1,5)], 
        lower = list(continuous = "smooth"),
        params = c(method = "loess"),
        axisLabels = "show")

谢谢!

另外，与plotmatrix函数相比，ggpairs要慢得多。因此，在大多数情况下，我只使用ggplot2中的plotmatrix。

Answer 1

文档上没有说，所以请使用源代码，Luke

1. 您可以使用以下命令更深入地挖掘源代码：

ls('package:GGally')

GGally::ggpairs

... and browse every function it references ...

seems like the args get mapped into ggpairsPlots and then -> plotMatrix which then gets called

因此，显然不支持显式地选择smoother，只能选择continuous = "smooth"。如果它的行为类似于ggplot2:geom_smooth，它会在内部自动找出调用哪个受支持的平滑器(对于<1000个数据点是loess，对于>=1000是gam )。您可能希望单步执行调试器，以查看绘图中发生了什么。我试着追查来源，但我的眼睛呆滞了。--

或2.浏览https://github.com/ggobi/ggally/blob/master/R/ggpairs.r 2013年4月14日

#' upper and lower are lists that may contain the variables 'continuous',
#' 'combo' and 'discrete'. Each element of the list is a string implementing
#' the following options: continuous = exactly one of ('points', 'smooth',
#' 'density', 'cor', 'blank') , ...
#'
#' diag is a list that may only contain the variables 'continuous' and 'discrete'.
#' Each element of the diag list is a string implmenting the following options:
#' continuous = exactly one of ('density', 'bar', 'blank');

Answer 2

通常，最好编写您自己的函数以供其使用。Adapted from this answer回答类似的问题。

library(GGally)
diamonds_sample = diamonds[sample(1:dim(diamonds)[1],200),]

# Function to return points and geom_smooth
# allow for the method to be changed
custom_function = function(data, mapping, method = "loess", ...){
      p = ggplot(data = data, mapping = mapping) + 
      geom_point() + 
      geom_smooth(method=method, ...)

      p
    }

# test it  
ggpairs(diamonds_sample,
    lower = list(continuous = custom_function)
)

生成以下内容：

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