R - 插槽无法访问？

Question

当我试图添加地理参考TIF-文件我的R中ggplots，我曾经遇到过一个看似怪异问题插槽：加载使用raster()光栅文件后，我无法达到其colortable -Slot：

>>Grab the example tif-file<<：

raster1 <- raster(paste(workingDir, "/HUEK200_Durchlaessigkeit001_proj001.tif", sep="", collapse="")) 
raster1@colortable #or 
slot(raster1, "colortable") 

最后两行shoudl效果一样，但无论是在错误信息导致：

Error in slot(raster1, "colortable") : 
    no slot of name "colortable" for this object of class "RasterLayer" 

这是令人困惑，因为小窥到通过attributes(raster1)属性明确列出正是插槽：

Slot "colortable": 
    [1] "#FFFFFF" "#000000" "#B49ED7" "#9B7DCF" "#9EAAD7" "#B2BEEB" "#B4EBB4" 
    [8] "#F5E1B5" "#CCB792" "#B9A08C" "#0070FF" "#0000C8" "#F8F8F8" "#DBF5FF" 
[15] "#B14D00" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[22] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[29] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[36] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[43] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[50] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[57] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[64] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[71] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[78] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[85] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[92] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[99] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[106] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[113] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[120] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[127] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[134] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[141] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[148] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[155] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[162] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[169] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[176] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[183] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[190] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[197] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[204] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[211] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[218] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[225] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[232] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[239] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[246] "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" "#000000" 
[253] "#000000" "#000000" "#000000" "#000000" 

难道我是谁做错事摆在首位，或者可以说，它是一个错误吗？我怎样才能最终访问colortable？我知道从调用plot(raster1)它应该工作，因为剧情显示正确的颜色集。此外：通常，在管理空间多边形对象时，S4object@someslot -approach对我来说工作得很好。

编辑： 除colortable之外，当尝试访问attributes(raster1)的其他插槽时出现相同的错误。

感谢您的帮助！

Answer 1

我现在已经找到了答案。我只是误解了attributes(raster1)的输出（不是完全明显的）。所述colortable -Slot不是直接的（第一顺序）的一部分光栅对象的接口，如果可以称之为liek在R.相反，它是在legend列出如下所示：R中

attr(raster1, "legend")@colortable 

参考总是倾向于让我感到惊讶！ :)