[R] sequential input script dataframe process functionality

[rl at openmailbox.org]

On 2014-09-10 10:45, PIKAL Petr wrote:
>> 
>> On 2014-09-08 15:47, William Dunlap wrote:
>> > d <- data.frame(Choices=c("One","Two","One","Three"), X=1:4)
>> > i <- 1 # possible output of menu(unique(d$Choices))
>> > d[ d$Choices[i] == d$Choices, ]
>> > #  Choices X
>> > #1     One 1
>> > #3     One 3
>> >
>> 
>> > testd <- data.frame(Choices=c("One","Two","One","Three"), X=1:4)
>> > testi <- 1 # possible output of menu(unique(d$Choices))
>> > testd[ testd$Choices[testi] == testd$Choices, ]
>>    Choices X
>> 1     One 1
>> 3     One 3
>> 
>> This instruction did not give any opportunity to enter a choice? Then
>> tried:
> 
> Why do you think so? Did you try it? Follow Wiliam's advice
> 
> d <- data.frame(Choices=c("One","Two","One","Three"), X=1:4)
> i <- menu(unique(d$Choices))
> 

It looks that you understood that 'menu...' was to be assigned to the 
variable 'i'; I did not understand, it was interpreted as a part of a 
comment, not a command to apply! :)

Of course, the menu function as you wrote it was successfully 
replicated. Thanks.

> 
> BTW, did you read R-intro? If not, why not?
> 

Yes, but for the benefit of other novices, information about 'menu' is 
accessible via '?menu' within R, or via R command 'help.start()' and web 
browser hyperlinks: 'packages','utils','menu'.