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Dimitri Liakhovitski

2016-Dec-08 23:02 UTC

[R] creating possible cominations of a vector's elements

Hello!

I have a vector of strings 'x' that was based on a longer string
'mystring' (the actual length of x is unknown).

mystring <- "this is my vector"
x <- strsplit(mystr, " ")[[1]]

I am looking for an elegant way of creating an object (e.g., a list)
that contains the following strings:

"this"
"this is"
"this is my"
"this is my vector"
"is"
"is my"
"is my vector"
"my"
"my vector"
"vector"

Thanks a lot!

-- 
Dimitri

David L Carlson

2016-Dec-08 23:51 UTC

head link

[R] creating possible cominations of a vector's elements

You can use expand.grid() and mapply():

mystring <- "this is my vector"
mystring.spl <- strsplit(mystring, " ")[[1]]

makestrings <- function(x) {
     len <- length(mystring.spl)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(mystring.spl[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}
makestrings(mystring.spl)

 [1] "this"              "this is"           "this is
my"
 [4] "this is my vector" "is"                "is
my"
 [7] "is my vector"      "my"                "my
vector"
[10] "vector"

This makes a vector of strings but if you want a list use as.list(mapply())

David L. Carlson
Department of Anthropology
Texas A&M University



-----Original Message-----
From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Dimitri
Liakhovitski
Sent: Thursday, December 8, 2016 5:03 PM
To: r-help <r-help at r-project.org>
Subject: [R] creating possible cominations of a vector's elements

Hello!

I have a vector of strings 'x' that was based on a longer string
'mystring' (the actual length of x is unknown).

mystring <- "this is my vector"
x <- strsplit(mystr, " ")[[1]]

I am looking for an elegant way of creating an object (e.g., a list)
that contains the following strings:

"this"
"this is"
"this is my"
"this is my vector"
"is"
"is my"
"is my vector"
"my"
"my vector"
"vector"

Thanks a lot!

-- 
Dimitri

______________________________________________
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.

Dimitri Liakhovitski

2016-Dec-08 23:58 UTC

head link

[R] creating possible cominations of a vector's elements

Thanks a lot, David - this is great!

On Thu, Dec 8, 2016 at 6:51 PM, David L Carlson <dcarlson at tamu.edu>
wrote:> You can use expand.grid() and mapply():
>
> mystring <- "this is my vector"
> mystring.spl <- strsplit(mystring, " ")[[1]]
>
> makestrings <- function(x) {
>      len <- length(mystring.spl)
>      idx <- expand.grid(1:len, 1:len)
>      idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
>      mapply(function(x, y) paste(mystring.spl[x:y], collapse="
"),
>           x=idx[, 1], y=idx[, 2])
> }
> makestrings(mystring.spl)
>
>  [1] "this"              "this is"           "this
is my"
>  [4] "this is my vector" "is"                "is
my"
>  [7] "is my vector"      "my"                "my
vector"
> [10] "vector"
>
> This makes a vector of strings but if you want a list use as.list(mapply())
>
> David L. Carlson
> Department of Anthropology
> Texas A&M University
>
>
>
> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Dimitri
Liakhovitski
> Sent: Thursday, December 8, 2016 5:03 PM
> To: r-help <r-help at r-project.org>
> Subject: [R] creating possible cominations of a vector's elements
>
> Hello!
>
> I have a vector of strings 'x' that was based on a longer string
> 'mystring' (the actual length of x is unknown).
>
> mystring <- "this is my vector"
> x <- strsplit(mystr, " ")[[1]]
>
> I am looking for an elegant way of creating an object (e.g., a list)
> that contains the following strings:
>
> "this"
> "this is"
> "this is my"
> "this is my vector"
> "is"
> "is my"
> "is my vector"
> "my"
> "my vector"
> "vector"
>
> Thanks a lot!
>
> --
> Dimitri
>
> ______________________________________________
> 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.


-- 
Dimitri Liakhovitski

William Dunlap

2016-Dec-09 00:05 UTC

head link

[R] creating possible cominations of a vector's elements

> ij <- combn(length(x)+1, 2)
> lapply(seq_len(ncol(ij)), function(k) x[ij[1,k]:(ij[2,k]-1)])[[1]]
[1] "this"

[[2]]
[1] "this" "is"
...
[[9]]
[1] "my"     "vector"

[[10]]
[1] "vector"


Bill Dunlap
TIBCO Software
wdunlap tibco.com

On Thu, Dec 8, 2016 at 3:02 PM, Dimitri Liakhovitski <
dimitri.liakhovitski at gmail.com> wrote:
> Hello!
>
> I have a vector of strings 'x' that was based on a longer string
> 'mystring' (the actual length of x is unknown).
>
> mystring <- "this is my vector"
> x <- strsplit(mystr, " ")[[1]]
>
> I am looking for an elegant way of creating an object (e.g., a list)
> that contains the following strings:
>
> "this"
> "this is"
> "this is my"
> "this is my vector"
> "is"
> "is my"
> "is my vector"
> "my"
> "my vector"
> "vector"
>
> Thanks a lot!
>
> --
> Dimitri
>
> ______________________________________________
> 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.
>
	[[alternative HTML version deleted]]

David L Carlson

2016-Dec-09 01:12 UTC

head link

[R] creating possible cominations of a vector's elements

This corrects an error in my earlier function definition:

makestrings <- function(vec) {
     len <- length(mystring.spl)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(vec[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}

David C

-----Original Message-----
From: David L Carlson 
Sent: Thursday, December 8, 2016 5:51 PM
To: 'Dimitri Liakhovitski' <dimitri.liakhovitski at gmail.com>;
r-help <r-help at r-project.org>
Subject: RE: [R] creating possible cominations of a vector's elements

You can use expand.grid() and mapply():

mystring <- "this is my vector"
mystring.spl <- strsplit(mystring, " ")[[1]]

makestrings <- function(x) {
     len <- length(mystring.spl)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(mystring.spl[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}
makestrings(mystring.spl)

 [1] "this"              "this is"           "this is
my"
 [4] "this is my vector" "is"                "is
my"
 [7] "is my vector"      "my"                "my
vector"
[10] "vector"

This makes a vector of strings but if you want a list use as.list(mapply())

David L. Carlson
Department of Anthropology
Texas A&M University



-----Original Message-----
From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Dimitri
Liakhovitski
Sent: Thursday, December 8, 2016 5:03 PM
To: r-help <r-help at r-project.org>
Subject: [R] creating possible cominations of a vector's elements

Hello!

I have a vector of strings 'x' that was based on a longer string
'mystring' (the actual length of x is unknown).

mystring <- "this is my vector"
x <- strsplit(mystr, " ")[[1]]

I am looking for an elegant way of creating an object (e.g., a list)
that contains the following strings:

"this"
"this is"
"this is my"
"this is my vector"
"is"
"is my"
"is my vector"
"my"
"my vector"
"vector"

Thanks a lot!

-- 
Dimitri

______________________________________________
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 L Carlson

2016-Dec-09 01:16 UTC

head link

[R] creating possible cominations of a vector's elements

Not my day. Another correction:

makestrings <- function(vec) {
     len <- length(vec)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(vec[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}

David C

-----Original Message-----
From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of David L
Carlson
Sent: Thursday, December 8, 2016 7:12 PM
To: Dimitri Liakhovitski <dimitri.liakhovitski at gmail.com>; r-help
<r-help at r-project.org>
Subject: Re: [R] creating possible cominations of a vector's elements

This corrects an error in my earlier function definition:

makestrings <- function(vec) {
     len <- length(mystring.spl)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(vec[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}

David C

-----Original Message-----
From: David L Carlson 
Sent: Thursday, December 8, 2016 5:51 PM
To: 'Dimitri Liakhovitski' <dimitri.liakhovitski at gmail.com>;
r-help <r-help at r-project.org>
Subject: RE: [R] creating possible cominations of a vector's elements

You can use expand.grid() and mapply():

mystring <- "this is my vector"
mystring.spl <- strsplit(mystring, " ")[[1]]

makestrings <- function(x) {
     len <- length(mystring.spl)
     idx <- expand.grid(1:len, 1:len)
     idx <- idx[idx$Var2 <= idx$Var1, c("Var2",
"Var1")]
     mapply(function(x, y) paste(mystring.spl[x:y], collapse=" "), 
          x=idx[, 1], y=idx[, 2])
}
makestrings(mystring.spl)

 [1] "this"              "this is"           "this is
my"
 [4] "this is my vector" "is"                "is
my"
 [7] "is my vector"      "my"                "my
vector"
[10] "vector"

This makes a vector of strings but if you want a list use as.list(mapply())

David L. Carlson
Department of Anthropology
Texas A&M University



-----Original Message-----
From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Dimitri
Liakhovitski
Sent: Thursday, December 8, 2016 5:03 PM
To: r-help <r-help at r-project.org>
Subject: [R] creating possible cominations of a vector's elements

Hello!

I have a vector of strings 'x' that was based on a longer string
'mystring' (the actual length of x is unknown).

mystring <- "this is my vector"
x <- strsplit(mystr, " ")[[1]]

I am looking for an elegant way of creating an object (e.g., a list)
that contains the following strings:

"this"
"this is"
"this is my"
"this is my vector"
"is"
"is my"
"is my vector"
"my"
"my vector"
"vector"

Thanks a lot!

-- 
Dimitri

______________________________________________
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 - Dec 2016 - creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements

[R] creating possible cominations of a vector's elements