r - 显示与特定类关联的方法

Question

我想查看与某个对象类关联的所有方法的列表。例如。如果我看到某个模型拟合例程返回一个“foo”类的对象，我想知道包(或任何其他包)是否定义了诸如 simulate.foo 之类的方法。 , update.foo , coef.foo , print.foo等等 我该怎么做？

我知道methods解决了逆问题(假设是 S3 类)，但显然我不想搜索定义了 print 的每个对象。函数以找出我感兴趣的类(class)是否有一个。我可能在这里忘记了一些非常简单的事情。谢谢!

(理想情况下，很高兴看到 S3 和 S4 类的解决方案)。

更新 :理想情况下，解决方案应该显示隐藏的方法，就像 methods 一样功能确实。例如，methods("simulate")显示:

> methods("simulate")
[1] simulate.lm*

所以在查询与 lm 相关的方法时类，我们想要恢复这个模拟方法。

Answer 1

我是笨蛋，还是methods(class="foo")你想要什么(对于 S3 方法)？？？

methods(class="lm")
##  [1] add1.lm*           alias.lm*          anova.lm           case.names.lm*    
##  [5] confint.lm*        cooks.distance.lm* deviance.lm*       dfbeta.lm*        
##  [9] dfbetas.lm*        drop1.lm*          dummy.coef.lm*     effects.lm*       
## [13] extractAIC.lm*     family.lm*         formula.lm*        hatvalues.lm      
## [17] influence.lm*      kappa.lm           labels.lm*         logLik.lm*        
## [21] model.frame.lm     model.matrix.lm    nobs.lm*           plot.lm           
## [25] predict.lm         print.lm           proj.lm*           qr.lm*            
## [29] residuals.lm       rstandard.lm       rstudent.lm        simulate.lm*      
## [33] summary.lm         variable.names.lm* vcov.lm*          
## 
##    Non-visible functions are asterisked

showMethods适用于 S4 类(class)(取自 @JoshO'Brien 现已删除的答案，供引用):

library(sp)
showMethods(classes="SpatialPolygons")

## Function: [ (package base)
## x="SpatialPolygons"
## 
## Function: addAttrToGeom (package sp)
## x="SpatialPolygons", y="data.frame"
## 
## Function: coerce (package methods)
## from="GridTopology", to="SpatialPolygons"
## from="SpatialGrid", to="SpatialPolygons"
## from="SpatialPixels", to="SpatialPolygons"
## from="SpatialPolygons", to="SpatialLines"
## from="SpatialPolygons", to="SpatialPolygonsDataFrame"
## 
## Function: coordinates (package sp)
## obj="SpatialPolygons"
## 
## Function: coordnames (package sp)
## x="SpatialPolygons"
## 
## Function: coordnames<- (package sp)
## x="SpatialPolygons", value="character"
## 
## Function: over (package sp)
## x="SpatialGrid", y="SpatialPolygons"
## x="SpatialPoints", y="SpatialPolygons"
## x="SpatialPolygons", y="SpatialGrid"
## x="SpatialPolygons", y="SpatialGridDataFrame"
## x="SpatialPolygons", y="SpatialPoints"
## x="SpatialPolygons", y="SpatialPointsDataFrame"
## 
## Function: overlay (package sp)
## x="SpatialGridDataFrame", y="SpatialPolygons"
## x="SpatialGrid", y="SpatialPolygons"
## x="SpatialPointsDataFrame", y="SpatialPolygons"
## x="SpatialPoints", y="SpatialPolygons"
## x="SpatialPolygons", y="SpatialGrid"
## x="SpatialPolygons", y="SpatialPoints"
## 
## Function: plot (package graphics)
## x="SpatialPolygons", y="missing"
## 
## Function: polygons (package sp)
## obj="SpatialPolygons"
## 
## Function: polygons<- (package sp)
## object="data.frame", value="SpatialPolygons"
## 
## Function: recenter (package sp)
## obj="SpatialPolygons"
## 
## Function: spChFIDs (package sp)
## obj="SpatialPolygons", x="character"
## 
## Function: spsample (package sp)
## x="SpatialPolygons"