[R] Adding SORT to UNIQUE

Rui Barradas ru|pb@rr@d@@ @end|ng |rom @@po@pt
Wed Dec 22 17:57:57 CET 2021 

Hello,

The problem is that the vectors of unique values in each column of the 
original data.frame Data need not be same length. And the output of 
sort(unique(.)) is a list of vectors of different lengths. And lists 
print "horizontally", each vector on its own.

Like Duncan said, one of the ways of getting a vertical display is to 
have the list of sorted, unique values be of a custom class and write a 
print method for that class. Here is an example of this. The function to 
sort outputs an object of a class that sub-classes class "list". And a 
print method takes care of the printing. This method creates a temp 
data.frame, prints that df and invisibly returns its input.

# Create a test data set
set.seed(2021)
Data <- replicate(4, as.character(sample(20, 20, TRUE)))
Data <- as.data.frame(Data)


# Now the functions
sort_unique <- function(x){
   y <- lapply(x, \(.x) stringr::str_sort(unique(.x), numeric = TRUE))
   old_class <- class(y)
   class(y) <- c("sortUnique", old_class)
   y
}
print.sortUnique <- function(x, ...){
   n <- max(lengths(x))
   y <- lapply(x, \(.x) c(.x, rep("", n - length(.x))))
   y <- do.call(cbind.data.frame, y)
   names(y) <- names(x)
   print(y)
   invisible(x)
}

# Test the functions above
Data2 <- sort_unique(Data)

class(Data2)
Data2
print(Data2)


Hope this helps,

Rui Barradas

Às 15:55 de 22/12/21, Stephen H. Dawson, DSL escreveu:
> I see.
> 
> So, we are talking taking the output into a new dataframe. I was hoping 
> to have the output rendered on screen without another dataframe, but I 
> can live with this option it if must occur.
> 
> Am I correct the desired vertical output must first go to a dataframe?
> 
> 
> *Stephen Dawson, DSL*
> /Executive Strategy Consultant/
> Business & Technology
> +1 (865) 804-3454
> http://www.shdawson.com <http://www.shdawson.com>
> 
> 
> On 12/22/21 10:47 AM, Duncan Murdoch wrote:
>> On 22/12/2021 10:20 a.m., Stephen H. Dawson, DSL wrote:
>>> Thanks for the reply.
>>>
>>> Both syntax options work to render the correct (unique) output. However,
>>> the output is rendered as horizontal. What needs to happen to get the
>>> output to render vertical, please?
>>
>> The result of those expressions is a vector of the same type as the 
>> column, so your question is really about how to get a vector to print 
>> one element per line.
>>
>> Probably the simplest way is to put the vector in a dataframe (or 
>> matrix, or tibble, depending on which formatting you prefer).  For 
>> example,
>>
>> >   v <- c("red", "green", "blue")
>> >   data.frame(v)
>>       v
>> 1   red
>> 2 green
>> 3  blue
>>
>> If you want a more minimal display, try
>>
>> > cat(v, sep = "\n")
>> red
>> green
>> blue
>>
>> or
>>
>> > cat(format(v, justify = "right"), sep = "\n")
>>   red
>> green
>>  blue
>>
>> If you want this to happen when you auto-print the object, you can 
>> give it a class attribute and write a function to print that class, e.g.
>>
>> >  class(v) <- "oneperline"
>> >
>> >   print.oneperline <- function(x, ...) cat(format(x, justify = 
>> "right"), sep = "\n")
>> >
>> >   v
>>   red
>> green
>>  blue
>>
>> Duncan Murdoch
>>
>>>
>>>
>>> *Stephen Dawson, DSL*
>>> /Executive Strategy Consultant/
>>> Business & Technology
>>> +1 (865) 804-3454
>>> http://www.shdawson.com <http://www.shdawson.com>
>>>
>>>
>>> On 12/21/21 11:38 AM, Duncan Murdoch wrote:
>>>> On 21/12/2021 11:31 a.m., Duncan Murdoch wrote:
>>>>> On 21/12/2021 11:20 a.m., Stephen H. Dawson, DSL wrote:
>>>>>> Thanks for the reply.
>>>>>>
>>>>>> sort(unique(Data[1]))
>>>>>> Error in `[.data.frame`(x, order(x, na.last = na.last, decreasing =
>>>>>> decreasing)) :
>>>>>>       undefined columns selected
>>>>>
>>>>> That's the wrong syntax:  Data[1] is not "column one of Data". Use
>>>>> Data[[1]] for that, so
>>>>>
>>>>>      sort(unique(Data[[1]]))
>>>>
>>>> Actually, I'd probably recommend
>>>>
>>>>    sort(unique(Data[, 1]))
>>>>
>>>> instead.  This treats Data as a matrix rather than as a list.
>>>> Dataframes are lists that look like matrices, but to me the matrix
>>>> aspect is usually more intuitive.
>>>>
>>>> Duncan Murdoch
>>>>
>>>>>
>>>>> I think Rui already pointed out the typo in the quoted text below...
>>>>>
>>>>> Duncan Murdoch
>>>>>
>>>>>>
>>>>>> The recommended syntax did not work, as listed above.
>>>>>>
>>>>>> What I want is the sort of distinct column output. Again, the column
>>>>>> may
>>>>>> be text or numbers. This is a huge analysis effort with data 
>>>>>> coming at
>>>>>> me from many different sources.
>>>>>>
>>>>>>
>>>>>> *Stephen Dawson, DSL*
>>>>>> /Executive Strategy Consultant/
>>>>>> Business & Technology
>>>>>> +1 (865) 804-3454
>>>>>> http://www.shdawson.com <http://www.shdawson.com>
>>>>>>
>>>>>>
>>>>>> On 12/21/21 11:07 AM, Duncan Murdoch wrote:
>>>>>>> On 21/12/2021 10:16 a.m., Stephen H. Dawson, DSL via R-help wrote:
>>>>>>>> Thanks everyone for the replies.
>>>>>>>>
>>>>>>>> It is clear one either needs to write a function or put the unique
>>>>>>>> entries into another dataframe.
>>>>>>>>
>>>>>>>> It seems odd R cannot sort a list of unique column entries with 
>>>>>>>> ease.
>>>>>>>> Python and SQL can do it with ease.
>>>>>>>
>>>>>>> I've seen several responses that looked pretty simple. It's hard to
>>>>>>> beat sort(unique(x)), though there's a fair bit of confusion about
>>>>>>> what you actually want.  Maybe you should post an example of the 
>>>>>>> code
>>>>>>> you'd use in Python?
>>>>>>>
>>>>>>> Duncan Murdoch
>>>>>>>
>>>>>>>>
>>>>>>>> QUESTION
>>>>>>>> Is there a simpler means than other than the unique function to
>>>>>>>> capture
>>>>>>>> distinct column entries, then sort that list?
>>>>>>>>
>>>>>>>>
>>>>>>>> *Stephen Dawson, DSL*
>>>>>>>> /Executive Strategy Consultant/
>>>>>>>> Business & Technology
>>>>>>>> +1 (865) 804-3454
>>>>>>>> http://www.shdawson.com <http://www.shdawson.com>
>>>>>>>>
>>>>>>>>
>>>>>>>> On 12/20/21 5:53 PM, Rui Barradas wrote:
>>>>>>>>> Hello,
>>>>>>>>>
>>>>>>>>> Inline.
>>>>>>>>>
>>>>>>>>> Às 21:18 de 20/12/21, Stephen H. Dawson, DSL via R-help escreveu:
>>>>>>>>>> Thanks.
>>>>>>>>>>
>>>>>>>>>> sort(unique(Data[[1]]))
>>>>>>>>>>
>>>>>>>>>> This syntax provides row numbers, not column values.
>>>>>>>>>
>>>>>>>>> This is not right.
>>>>>>>>> The syntax Data[1] extracts a sub-data.frame, the syntax Data[[1]]
>>>>>>>>> extracts the column vector.
>>>>>>>>>
>>>>>>>>> As for my previous answer, it was not addressing the question, I
>>>>>>>>> misinterpreted it as being a question on how to sort by numeric
>>>>>>>>> order
>>>>>>>>> when the data is not numeric. Here is a, hopefully, complete 
>>>>>>>>> answer.
>>>>>>>>> Still with package stringr.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> cols_to_sort <- 1:4
>>>>>>>>>
>>>>>>>>> Data2 <- lapply(Data[cols_to_sort], \(x){
>>>>>>>>>       stringr::str_sort(unique(x), numeric = TRUE)
>>>>>>>>> })
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Or using Avi's suggestion of writing a function to do all the
>>>>>>>>> work and
>>>>>>>>> simplify the lapply loop later,
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> unisort2 <- function(vec, ...) stringr::str_sort(unique(vec), ...)
>>>>>>>>> Data2 <- lapply(Data[cols_to_sort], unisort, numeric = TRUE)
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Hope this helps,
>>>>>>>>>
>>>>>>>>> Rui Barradas
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> *Stephen Dawson, DSL*
>>>>>>>>>> /Executive Strategy Consultant/
>>>>>>>>>> Business & Technology
>>>>>>>>>> +1 (865) 804-3454
>>>>>>>>>> http://www.shdawson.com <http://www.shdawson.com>
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 12/20/21 11:58 AM, Stephen H. Dawson, DSL via R-help wrote:
>>>>>>>>>>> Hi,
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Running a simple syntax set to review entries in dataframe
>>>>>>>>>>> columns.
>>>>>>>>>>> Here is the working code.
>>>>>>>>>>>
>>>>>>>>>>> Data <- read.csv("./input/Source.csv", header=T)
>>>>>>>>>>> describe(Data)
>>>>>>>>>>> summary(Data)
>>>>>>>>>>> unique(Data[1])
>>>>>>>>>>> unique(Data[2])
>>>>>>>>>>> unique(Data[3])
>>>>>>>>>>> unique(Data[4])
>>>>>>>>>>>
>>>>>>>>>>> I would like to add sort the unique entries. The data in the
>>>>>>>>>>> various
>>>>>>>>>>> columns are not defined as numbers, but also text. I realize 
>>>>>>>>>>> 1 and
>>>>>>>>>>> 10 will not sort properly, as the column is not defined as a
>>>>>>>>>>> number,
>>>>>>>>>>> but want to see what I have in the columns viewed as sorted.
>>>>>>>>>>>
>>>>>>>>>>> QUESTION
>>>>>>>>>>> What is the best process to sort unique output, please?
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> Thanks.
>>>>>>>>>>
>>>>>>>>>> ______________________________________________
>>>>>>>>>> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>>>>>>>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>>>>>>>>> PLEASE do read the posting guide
>>>>>>>>>> http://www.R-project.org/posting-guide.html
>>>>>>>>>> and provide commented, minimal, self-contained, reproducible 
>>>>>>>>>> code.
>>>>>>>>>
>>>>>>>>
>>>>>>>> ______________________________________________
>>>>>>>> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>>>>>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>>>>>>> PLEASE do read the posting guide
>>>>>>>> http://www.R-project.org/posting-guide.html
>>>>>>>> and provide commented, minimal, self-contained, reproducible code.
>>>>>>>
>>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>>
>>
>>
>

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