Concatenate a Vector of Strings/Character

Concatenate a vector of strings/character

Try using an empty collapse argument within the paste function:

paste(sdata, collapse = '')

Thanks to http://twitter.com/onelinetips/status/7491806343

concatenate vector of strings into a single string - for each row in df

You are close to the right code, just add collapse and work on rows with margin=1:

apply(data, 1, paste,collapse=" ")
[1] "abc fghi m" " j "        "de kl "

from documentation

collapse an optional character string to separate the results.

To integrate the output in your dataset:

data$pasted<-apply(data, 1, paste,collapse=" ")
> data
   x1   x2 x3     pasted
1 abc fghi  m abc fghi m
2        j            j 
3  de   kl        de kl 

Concatenate unique combinations of elements in a character vector into new vector of strings in R

Try combn

> sprintf("_%s_", combn(vec, 2, paste0, collapse = "_"))
 [1] "_X1_X2_" "_X1_X3_" "_X1_X4_" "_X1_X5_" "_X2_X3_" "_X2_X4_" "_X2_X5_"
 [8] "_X3_X4_" "_X3_X5_" "_X4_X5_"

> paste0("_", combn(vec, 2, paste0, collapse = "_"), "_")
 [1] "_X1_X2_" "_X1_X3_" "_X1_X4_" "_X1_X5_" "_X2_X3_" "_X2_X4_" "_X2_X5_"
 [8] "_X3_X4_" "_X3_X5_" "_X4_X5_"

Concatenate Strings to a Vector of Strings

From the last line of your question, may be you had a patttern like this in mind:

julia> string.("The font face is ", faces)
3-element Vector{String}:
 "The font face is bold"
 "The font face is ital"
 "The font face is code"

Semantically, this and the .* solution and the map solution are ultimately doing the same thing, but perhaps you have a preference for this syntax.

How can I concatenate a vector?

Try using:

> paste(blah, collapse = "")
[1] "p30s4p28s4"

or if you want the space in between:

> paste(blah, collapse = " ")
[1] "p30s4 p28s4"

Julia: how to concatenate characters of vector together ([a, b, c] - abc)

There are a variety of ways to concatenate a vector of strings:

• join function
• string function
• * concatenate function

as shown by the various comments.

However, the calling signatures for these functions are not identical. I did not notice this at first, and someone else new to Julia might appreciate the details.

julia> j = join(a)
"abc"

julia> s = string(a...)
"abc"

julia> m = *(a...)
"abc"

# When called correctly all three functions return equivalent results.
julia> j == s == m
true

However, when someone, like myself, is new to Julia, they might not immediately recognize (I didn't) the critical importance of ... for the string and * string concatenate functions, in contrast to the join function.

For example:

julia> s2 = string(a)
"[\"a\", \"b\", \"c\"]"

julia> s == s2
false

# or simply:
julia> join(a) == string(a)
false

What is the difference between s = join(a) and s2 = string(a)?

# Note that join(a) produces a string of 3 letters, "abc".
julia> length(s)
3

# string(a) produces a string of punctuation characters with the letters.
julia> length(s2)
15

julia> s[1]
'a': ASCII/Unicode U+0061 (category Ll: Letter, lowercase)

julia> s2[1]
'[': ASCII/Unicode U+005b (category Ps: Punctuation, open)

julia> s[1:3]
"abc"

julia> s2[1:3]
"[\"a"

The *() concatenation function is also quite different from the join function:

julia> a = ["a", "b", "c"]
3-element Array{String,1}:
 "a"
 "b"
 "c"

julia> j = join(a)
"abc"

julia> m = *(a)
ERROR: MethodError: no method matching *(::Array{String,1})

julia> m = *(a...)
"abc"

Thus the "splat" operator, ..., which is used to apply a function to a sequence of arguments is crucial to string and *, but not to join.

In fact, the join function with the "splat" operator does something you probably don't want:

julia> join(a...)
"a"

How to concatenate a string to each element of a possible empty character vector?

OUTDATED (still valid for R <4.0.1):

---

While writing this question, I found an almost satisfying answer:

new_people <- c(" R. A. Becker", "J. M. Chambers", "A. R. Wilks")
sprintf("Hello %s!", new_people)
# [1] "Hello  R. A. Becker!"  "Hello J. M. Chambers!" "Hello A. R. Wilks!"   

new_people <- character()
sprintf("Hello %s!", new_people)
# character(0)

This, however, lacks the nice linkage between the variables and their position in the string that paste has and requires an additional surrounding paste(..., collapse="") if one wants to smush the strings together.

concatenate strings in a character vector based on element names

We can concatenate with paste by using grouping variables as the names of the vector 'a'

tapply(a, names(a), FUN = paste, collapse = ' ')
#            item 1               item 2 
#"first_i1 second_i2"            "only_i2" 

---

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