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Ian Arvin

2012-Oct-04 14:20 UTC

[R] Subsetting a group of data

Hi,


I am making my way down the learning curve of R, and find it a great
language with so many helpful users!

Below is an example of what I'm trying to do, but can't quite figure out
the
right path to go down.

 

Here's what I have:

 

Main is a time series of data with columns Cola and Colb

                Cola       Colb

1              1              1

2              1              1

3              1              1

4              -1            1

5              -1            -1

6              -1            -1

7              1              -1

8              -1            -1

9              -1            -1

10           -1            -1

 

What I would like is to subset the data into groups -  rows 1-3 into one
group (Cola and Colb both =1), then row 4 by itself, then rows 5-6, then row
7, then rows 8-10.

Group 1

                Cola       Colb

1              1              1

2              1              1

3              1              1

 

Group 2

                Cola       Colb

1              -1            1

 

Group 3

                Cola       Colb

1              -1            -1

2              -1            -1

 

Thank you for your help!

 

Ian

 

 


	[[alternative HTML version deleted]]

R. Michael Weylandt

2012-Oct-04 15:35 UTC

head link

[R] Subsetting a group of data

On Thu, Oct 4, 2012 at 3:20 PM, Ian Arvin <ian at innovativequant.com>
wrote:> Hi,
>
>
> I am making my way down the learning curve of R, and find it a great
> language with so many helpful users!
Up it hopefully, no?
>
> Below is an example of what I'm trying to do, but can't quite
figure out the
> right path to go down.
>
>
>
> Here's what I have:
>
>
>
> Main is a time series of data with columns Cola and Colb
>
>                 Cola       Colb
>
> 1              1              1
>
> 2              1              1
>
> 3              1              1
>
> 4              -1            1
>
> 5              -1            -1
>
> 6              -1            -1
>
> 7              1              -1
>
> 8              -1            -1
>
> 9              -1            -1
>
> 10           -1            -1
>
>
>
> What I would like is to subset the data into groups -  rows 1-3 into one
> group (Cola and Colb both =1), then row 4 by itself, then rows 5-6, then
row
> 7, then rows 8-10.
>
> Group 1
>
>                 Cola       Colb
>
> 1              1              1
>
> 2              1              1
>
> 3              1              1
>
>
>
> Group 2
>
>                 Cola       Colb
>
> 1              -1            1
>
>
>
> Group 3
>
>                 Cola       Colb
>
> 1              -1            -1
>
> 2              -1            -1
>
>
>
Short answer is to ask why you want to do this? There are many
functions which operate on the split-->apply-->combine paradigm (see
the JSS article of that name for a short intro) but I find it easier
to do this in conjunction with specifying what my data transformation
is.

To directly answer your question, you'll probably need to combine
split() and interaction() in some way.

Cheers,
Michael

Rui Barradas

2012-Oct-04 15:56 UTC

head link

[R] Subsetting a group of data

Hello,

Try the following.


dat <- read.table(text="
Cola       Colb
1              1              1
2              1              1
3              1              1
4              -1            1
5              -1            -1
6              -1            -1
7              1              -1
8              -1            -1
9              -1            -1
10           -1            -1
", header=TRUE)

idx <- dat$Cola != dat$Colb
split(dat, 2*cumsum(idx) - idx)


Hope this helps,

Rui Barradas
Em 04-10-2012 15:20, Ian Arvin escreveu:> Hi,
>
>
> I am making my way down the learning curve of R, and find it a great
> language with so many helpful users!
>
> Below is an example of what I'm trying to do, but can't quite
figure out the
> right path to go down.
>
>   
>
> Here's what I have:
>
>   
>
> Main is a time series of data with columns Cola and Colb
>
>                  Cola       Colb
>
> 1              1              1
>
> 2              1              1
>
> 3              1              1
>
> 4              -1            1
>
> 5              -1            -1
>
> 6              -1            -1
>
> 7              1              -1
>
> 8              -1            -1
>
> 9              -1            -1
>
> 10           -1            -1
>
>   
>
> What I would like is to subset the data into groups -  rows 1-3 into one
> group (Cola and Colb both =1), then row 4 by itself, then rows 5-6, then
row
> 7, then rows 8-10.
>
> Group 1
>
>                  Cola       Colb
>
> 1              1              1
>
> 2              1              1
>
> 3              1              1
>
>   
>
> Group 2
>
>                  Cola       Colb
>
> 1              -1            1
>
>   
>
> Group 3
>
>                  Cola       Colb
>
> 1              -1            -1
>
> 2              -1            -1
>
>   
>
> Thank you for your help!
>
>   
>
> Ian
>
>   
>
>   
>
>
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org mailing list
> 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.

arun

2012-Oct-04 22:20 UTC

head link

[R] Subsetting a group of data

Hi,
You can also try this:
dat1 <- read.table(text="
Cola?????? Colb
1????????????? 1????????????? 1
2????????????? 1????????????? 1
3????????????? 1????????????? 1
4????????????? -1??????????? 1
5????????????? -1??????????? -1
6????????????? -1??????????? -1
7????????????? 1????????????? -1
8????????????? -1??????????? -1
9????????????? -1??????????? -1
10?????????? -1??????????? -1
", header=TRUE)

idx<- c(0,cumsum(abs(diff(dat1$Cola))))-as.integer(dat1$Cola!=dat1$Colb)
?split(dat1,idx)

A.K.

----- Original Message -----
From: Ian Arvin <ian at innovativequant.com>
To: r-help at r-project.org
Cc: 
Sent: Thursday, October 4, 2012 10:20 AM
Subject: [R] Subsetting a group of data

Hi,


I am making my way down the learning curve of R, and find it a great
language with so many helpful users!

Below is an example of what I'm trying to do, but can't quite figure out
the
right path to go down.



Here's what I have:



Main is a time series of data with columns Cola and Colb

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

2? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

3? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

4? ? ? ? ? ? ? -1? ? ? ? ? ? 1

5? ? ? ? ? ? ? -1? ? ? ? ? ? -1

6? ? ? ? ? ? ? -1? ? ? ? ? ? -1

7? ? ? ? ? ? ? 1? ? ? ? ? ? ? -1

8? ? ? ? ? ? ? -1? ? ? ? ? ? -1

9? ? ? ? ? ? ? -1? ? ? ? ? ? -1

10? ? ? ? ?  -1? ? ? ? ? ? -1



What I would like is to subset the data into groups -? rows 1-3 into one
group (Cola and Colb both =1), then row 4 by itself, then rows 5-6, then row
7, then rows 8-10.

Group 1

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

2? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

3? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1



Group 2

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? -1? ? ? ? ? ? 1



Group 3

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? -1? ? ? ? ? ? -1

2? ? ? ? ? ? ? -1? ? ? ? ? ? -1



Thank you for your help!



Ian






??? [[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
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.

arun

2012-Oct-05 04:24 UTC

head link

[R] Subsetting a group of data

HI,
Another way to get the result:
dat1 <- read.table(text="
Cola?????? Colb
1????????????? 1????????????? 1
2????????????? 1????????????? 1
3????????????? 1????????????? 1
4????????????? -1??????????? 1
5????????????? -1??????????? -1
6????????????? -1??????????? -1
7????????????? 1????????????? -1
8????????????? -1??????????? -1
9????????????? -1??????????? -1
10?????????? -1??????????? -1
", header=TRUE)
list1<-split(dat1,within(dat1,{new1<-as.numeric(unlist(strsplit(gsub("AAA(\\d)AA(\\d).*","111\\133\\2555",gsub("(.*)B(.*)B(.*)","\\12\\24\\3",paste(ifelse(dat1$Cola==dat1$Colb,"A","B"),collapse=""))),"")))})[,3])
list1
#$`1`
?# Cola Colb
#1??? 1??? 1
#2??? 1??? 1
#3??? 1??? 1

#$`2`
?# Cola Colb
#4?? -1??? 1

#$`3`
?# Cola Colb
#5?? -1?? -1
#6?? -1?? -1

#$`4`
?# Cola Colb
#7??? 1?? -1

#$`5`
?#? Cola Colb
#8??? -1?? -1
#9??? -1?? -1
#10?? -1?? -1


A.K.

----- Original Message -----
From: Ian Arvin <ian at innovativequant.com>
To: r-help at r-project.org
Cc: 
Sent: Thursday, October 4, 2012 10:20 AM
Subject: [R] Subsetting a group of data

Hi,


I am making my way down the learning curve of R, and find it a great
language with so many helpful users!

Below is an example of what I'm trying to do, but can't quite figure out
the
right path to go down.



Here's what I have:



Main is a time series of data with columns Cola and Colb

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

2? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

3? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

4? ? ? ? ? ? ? -1? ? ? ? ? ? 1

5? ? ? ? ? ? ? -1? ? ? ? ? ? -1

6? ? ? ? ? ? ? -1? ? ? ? ? ? -1

7? ? ? ? ? ? ? 1? ? ? ? ? ? ? -1

8? ? ? ? ? ? ? -1? ? ? ? ? ? -1

9? ? ? ? ? ? ? -1? ? ? ? ? ? -1

10? ? ? ? ?  -1? ? ? ? ? ? -1



What I would like is to subset the data into groups -? rows 1-3 into one
group (Cola and Colb both =1), then row 4 by itself, then rows 5-6, then row
7, then rows 8-10.

Group 1

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

2? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1

3? ? ? ? ? ? ? 1? ? ? ? ? ? ? 1



Group 2

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? -1? ? ? ? ? ? 1



Group 3

? ? ? ? ? ? ? ? Cola? ? ?  Colb

1? ? ? ? ? ? ? -1? ? ? ? ? ? -1

2? ? ? ? ? ? ? -1? ? ? ? ? ? -1



Thank you for your help!



Ian






??? [[alternative HTML version deleted]]

______________________________________________
R-help at r-project.org mailing list
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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