#switch
switch(Statement,list)
تابعی که بر اساس ان میتوان چندین دستور را کنار یکدیگر قرار داد " ی لیست " و به دلخواه اون هارو فراخوانی کرد

 switch(2,"red","green","blue")
[1] "green"

> switch(1,"red","green","blue")
[1] "red" 

 x <- switch(4,"red","green","blue")
> x
NULL

> x <- switch(0,"red","green","blue")
> x
NULL

> switch("color", "color" = "red", "shape" = "square", "length" = 5)
[1] "red"

> switch("length", "color" = "red", "shape" = "square", "length" = 5)
[1] 5

@R_Experts