R help - Feb 2015 - Substituting elements in vector

Dear list,

I have a vector:
my.vector <- c("A", "B", "C", "D",
"E", "F", "G")

and two other:
vec1 <- c("p", "q", "r", "s",
"t")
vec2 <- c("x", "y", "z")

I want to substitute elements "b" and "e" in my.vector with
vectors vec1 and
vec2 respectively so that the result becomes the vector:
c("A", "p", "q", "r" , "s" ,
"t", "C" , "D", "x", "y",
"z", "F", "G")

The ordering of the elements is important.

Knut Hansen

> On 17-02-2015, at 12:58, Knut Hansen <knut.hansen at uit.no> wrote:
> 
> Dear list,
> 
> I have a vector:
> my.vector <- c("A", "B", "C",
"D", "E", "F", "G")
> 
> and two other:
> vec1 <- c("p", "q", "r", "s",
"t")
> vec2 <- c("x", "y", "z")
> 
> I want to substitute elements "b" and "e" in my.vector
with vectors vec1 and
> vec2 respectively so that the result becomes the vector:
> c("A", "p", "q", "r" ,
"s" , "t", "C" , "D", "x",
"y", "z", "F", "G")
> 
> The ordering of the elements is important.
> 
Something like this perhaps

res <- c("A", "p", "q", "r" ,
"s" , "t", "C" , "D", "x",
"y", "z", "F", "G?)

rem <- function(vec, who, replace){
	kW <- which(vec == who)
	z1 <- append(vec,replace,kW)
	z2 <- z1[ ! z1 %in% vec[kW] ]
	z2
}

x1 <- rem(my.vector,"B",vec1)
x2 <- rem(x1,"E",vec2)
x2
all.equal(x2,res)

Berend

Hi,

  Here is an implementation.
> my.vector
[1] "A" "B" "C" "D" "E"
"F" "G"
> vec1
[1] "p" "q" "r" "s"
"t"
> vec2
[1] "x" "y" "z"
> final <- as.character(unlist(sapply(my.vector,function(x)
> if(x=="B"){vec1}else{if(x=="E"){vec2}else{x}})))
> final
 [1] "A" "p" "q" "r" "s"
"t" "C" "D" "x" "y"
"z" "F" "G"



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On Feb 17, 2015, at 3:58 AM, Knut Hansen wrote:
> Dear list,
> 
> I have a vector:
> my.vector <- c("A", "B", "C",
"D", "E", "F", "G")
> 
> and two other:
> vec1 <- c("p", "q", "r", "s",
"t")
> vec2 <- c("x", "y", "z")
> 
> I want to substitute elements "b" and "e" in my.vector
with vectors vec1 and
> vec2 respectively so that the result becomes the vector:
> c("A", "p", "q", "r" ,
"s" , "t", "C" , "D", "x",
"y", "z", "F", "G")
> my.vlist <- setNames(as.list(my.vector),my.vector)
> replist <- list(B=vec1, E=vec2)
> my.vlist[c("B","E")] <- replist
> unlist(my.vlist)
  A  B1  B2  B3  B4  B5   C   D  E1  E2  E3   F   G 
"A" "p" "q" "r" "s"
"t" "C" "D" "x" "y"
"z" "F" "G"

Could also have used:

my.vlist[ names(replist) ] <- replist

.... which I think illustrates the value of character indexing of lists for
assignment even better.

> The ordering of the elements is important.
> 
> Knut Hansen
> 
> 
David Winsemius
Alameda, CA, USA

Tirsdag 17. februar 2015 15.50.27 skrev David Winsemius:
> On Feb 17, 2015, at 3:58 AM, Knut Hansen wrote:
> > Dear list,
> > 
> > I have a vector:
> > my.vector <- c("A", "B", "C",
"D", "E", "F", "G")
> > 
> > and two other:
> > vec1 <- c("p", "q", "r",
"s", "t")
> > vec2 <- c("x", "y", "z")
> > 
> > I want to substitute elements "b" and "e" in
my.vector with vectors vec1
> > and vec2 respectively so that the result becomes the vector:
> > c("A", "p", "q", "r" ,
"s" , "t", "C" , "D", "x",
"y", "z", "F", "G")
> > 
> > my.vlist <- setNames(as.list(my.vector),my.vector)
> > replist <- list(B=vec1, E=vec2)
> > my.vlist[c("B","E")] <- replist
> > unlist(my.vlist)
> 
>   A  B1  B2  B3  B4  B5   C   D  E1  E2  E3   F   G
> "A" "p" "q" "r" "s"
"t" "C" "D" "x" "y"
"z" "F" "G"
> 
> Could also have used:
> 
> my.vlist[ names(replist) ] <- replist
> 
> .... which I think illustrates the value of character indexing of lists for
> assignment even better.
> > The ordering of the elements is important.
> > 
> > Knut Hansen
> 
> David Winsemius
> Alameda, CA, USA
Thank you. This was what I was looking for. I was not aware of named lists in 
R, and I was about to write a script in Python to fix this.

Knut Hansen