[R] Remove
David Winsemius
dwinsemius at comcast.net
Sat Dec 9 18:38:26 CET 2017
> On Dec 8, 2017, at 6:16 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>
>
>> On Dec 8, 2017, at 4:48 PM, Ashta <sewashm at gmail.com> wrote:
>>
>> Hi David, Ista and all,
>>
>> I have one related question Within one group I want to keep records
>> conditionally.
>> example within
>> group A I want keep rows that have " x" values ranged between 15 and 30.
>> group B I want keep rows that have " x" values ranged between 40 and 50.
>> group C I want keep rows that have " x" values ranged between 60 and 75.
>
> When you have a problem where there are multiple "parallel: parameters, the function to "reach for" is `mapply`.
>
> mapply( your_selection_func, group_vec, min_vec, max_vec)
>
> ... and this will probably return the values as a list (of dataframes if you build the function correctly, so you may may need to then do:
>
> do.call(rbind, ...)
do.call( rbind,
mapply( function(dat, grp, minx, maxx) {dat[ dat$GR==grp & dat$x >= minx & dat$x <= maxx, ]},
grp=LETTERS[1:3], minx=c(15,40,60), maxx=c(30,50,75) ,
MoreArgs=list(dat=DM),
IMPLIFY=FALSE))
GR x y
A.1 A 25 125
A.2 A 23 135
B.5 B 45 321
B.6 B 47 512
C.9 C 61 521
C.10 C 68 235
>
> --
> David.
>>
>>
>> DM <- read.table( text='GR x y
>> A 25 125
>> A 23 135
>> A 14 145
>> A 35 230
>> B 45 321
>> B 47 512
>> B 53 123
>> B 55 451
>> C 61 521
>> C 68 235
>> C 85 258
>> C 80 654',header = TRUE, stringsAsFactors = FALSE)
>>
>>
>> The end result will be
>> A 25 125
>> A 23 135
>> B 45 321
>> B 47 512
>> C 61 521
>> C 68 235
>>
>> Thank you
>>
>> On Wed, Dec 6, 2017 at 10:34 PM, David Winsemius <dwinsemius at comcast.net> wrote:
>>>
>>>> On Dec 6, 2017, at 4:27 PM, Ashta <sewashm at gmail.com> wrote:
>>>>
>>>> Thank you Ista! Worked fine.
>>>
>>> Here's another (possibly more direct in its logic?):
>>>
>>> DM[ !ave(DM$x, DM$GR, FUN= function(x) {!length(unique(x))==1}), ]
>>> GR x y
>>> 5 B 25 321
>>> 6 B 25 512
>>> 7 B 25 123
>>> 8 B 25 451
>>>
>>> --
>>> David
>>>
>>>> On Wed, Dec 6, 2017 at 5:59 PM, Ista Zahn <istazahn at gmail.com> wrote:
>>>>> Hi Ashta,
>>>>>
>>>>> There are many ways to do it. Here is one:
>>>>>
>>>>> vars <- sapply(split(DM$x, DM$GR), var)
>>>>> DM[DM$GR %in% names(vars[vars > 0]), ]
>>>>>
>>>>> Best
>>>>> Ista
>>>>>
>>>>> On Wed, Dec 6, 2017 at 6:58 PM, Ashta <sewashm at gmail.com> wrote:
>>>>>> Thank you Jeff,
>>>>>>
>>>>>> subset( DM, "B" != x ), this works if I know the group only.
>>>>>> But if I don't know that group in this case "B", how do I identify
>>>>>> group(s) that all elements of x have the same value?
>>>>>>
>>>>>> On Wed, Dec 6, 2017 at 5:48 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote:
>>>>>>> subset( DM, "B" != x )
>>>>>>>
>>>>>>> This is covered in the Introduction to R document that comes with R.
>>>>>>> --
>>>>>>> Sent from my phone. Please excuse my brevity.
>>>>>>>
>>>>>>> On December 6, 2017 3:21:12 PM PST, David Winsemius <dwinsemius at comcast.net> wrote:
>>>>>>>>
>>>>>>>>> On Dec 6, 2017, at 3:15 PM, Ashta <sewashm at gmail.com> wrote:
>>>>>>>>>
>>>>>>>>> Hi all,
>>>>>>>>> In a data set I have group(GR) and two variables x and y. I want to
>>>>>>>>> remove a group that have the same record for the x variable in each
>>>>>>>>> row.
>>>>>>>>>
>>>>>>>>> DM <- read.table( text='GR x y
>>>>>>>>> A 25 125
>>>>>>>>> A 23 135
>>>>>>>>> A 14 145
>>>>>>>>> A 12 230
>>>>>>>>> B 25 321
>>>>>>>>> B 25 512
>>>>>>>>> B 25 123
>>>>>>>>> B 25 451
>>>>>>>>> C 11 521
>>>>>>>>> C 14 235
>>>>>>>>> C 15 258
>>>>>>>>> C 10 654',header = TRUE, stringsAsFactors = FALSE)
>>>>>>>>>
>>>>>>>>> In this example the output should contain group A and C as group B
>>>>>>>>> has the same record for the variable x .
>>>>>>>>>
>>>>>>>>> The result will be
>>>>>>>>> A 25 125
>>>>>>>>> A 23 135
>>>>>>>>> A 14 145
>>>>>>>>> A 12 230
>>>>>>>>> C 11 521
>>>>>>>>> C 14 235
>>>>>>>>> C 15 258
>>>>>>>>> C 10 654
>>>>>>>>
>>>>>>>> Try:
>>>>>>>>
>>>>>>>> DM[ !duplicated(DM$x) , ]
>>>>>>>>>
>>>>>>>>> How do I do it R?
>>>>>>>>> Thank you.
>>>>>>>>>
>>>>>>>>> ______________________________________________
>>>>>>>>> R-help at 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.
>>>>>>>>
>>>>>>>> David Winsemius
>>>>>>>> Alameda, CA, USA
>>>>>>>>
>>>>>>>> 'Any technology distinguishable from magic is insufficiently advanced.'
>>>>>>>> -Gehm's Corollary to Clarke's Third Law
>>>>>>>>
>>>>>>>> ______________________________________________
>>>>>>>> R-help at 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 at 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 at 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.
>>>
>>> David Winsemius
>>> Alameda, CA, USA
>>>
>>> 'Any technology distinguishable from magic is insufficiently advanced.' -Gehm's Corollary to Clarke's Third Law
>>>
>>>
>>>
>>>
>>>
>
> David Winsemius
> Alameda, CA, USA
>
> 'Any technology distinguishable from magic is insufficiently advanced.' -Gehm's Corollary to Clarke's Third Law
>
> ______________________________________________
> R-help at 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.
David Winsemius
Alameda, CA, USA
'Any technology distinguishable from magic is insufficiently advanced.' -Gehm's Corollary to Clarke's Third Law
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