MathWit entry/demo course - Math0

Sometimes you quit R a few days ago but you can still access time variables you defined. You can type: objects(), then the objects you defined earlier will appear. > objects() [1] "%newop%"   "0+3=3"   "a" [4] "a+b=c"   "b"   "cc"   [7] "d"   "data"   "group_frame" [10] "groups"   "height"   "i"   [13] "iter0"   "list"   "list_1"   [16] "m"   "m2"   "new_list" [19] "switchdemo.switch"  "t"   "t1" [22] "t2"   "t3"   "t4" [25] "test"   "test2"   "test3" [28] "test4"   "test5"   "test6" [31] "u"   "v"   "weight" [34] "x"   "x5"   "x6" [37] "y"   "z"   "zzz"  

 To remove some objects, you can do as the following, then verify indeed, they are removed.

  > rm(zzz,`0+3=3`) > objects() [1] "%newop%" "a" "a+b=c" [4] "b" "cc" "d" [7] "data" "group_frame" "groups" [10] "height" "i" "iter0" [13] "list" "list_1" "m" [16] "m2" "new_list" "switchdemo.switch" [19] "t" "t1" "t2" [22] "t3" "t4" "test" [25] "test2" "test3" "test4" [28] "test5" "test6" "u" [31] "v" "weight" "x" [34] "x5" "x6" "y" [37] "z"

Now you can also observe the following code and sample output:

> ls() [1] "%newop%" "a" "a+b=c" "b" "cc" "d" "data" [8] "env.demo" "group_frame" "groups" "height" "i" "iter0" "list" [15] "list_1" "m" "m2" "new_list" "openfile" "switchdemo.switch" "t" [22] "t1" "t2" "t3" "t4" "test" "test2" "test3" [29] "test4" "test5" "test6" "u" "v" "weight" "x" [36] "x5" "x6" "y" "z" > rm(list = ls()) > ls() character(0)