R devel - Dec 2009 - binary string conversion to a vector (PR#14120)

Full_Name: Franc Brglez
Version: R 2.9.1 GUI 1.28 Tiger build 32-bit (5444)
OS: MacOSX -- 10.6.2
Submission from: (NULL) (24.148.163.114)


I am demonstrating what may be a bug or my lack of experience. Please review as
it would help to hear from someone.
MANY THANKS -- Franc Brglez

The function "binS2binV" returns what I consider a wrong value -- see
the
terminal output

binS2binV = function(string="0001101", sep="") 
# this procedure is expected to convert a binary string to a binary vector ...
# but does it?? Why do we get a vector with quoted binary values??
{   
    qlist = strsplit(string, sep)
    qvector = qlist[[1]]
    cat("\n  string=", string)
    cat("\n qvector=", qvector)
    n = length(qvector) ; xvector = NULL
    for (i in 1:n) {
	tmp = noquote(qvector[i])
	cat("\n", i,",     tmp=", tmp)
	xvector = c(xvector, tmp)
	cat("\n", i,", xvector=", xvector)
    }
    cat("\n")
    return(xvector)
}
> print(binS2binV("10101100"))
  string= 10101100
 qvector= 1 0 1 0 1 1 0 0
 1 ,     tmp= 1
 1 , xvector= 1
 2 ,     tmp= 0
 2 , xvector= 1 0
 3 ,     tmp= 1
 3 , xvector= 1 0 1
 4 ,     tmp= 0
 4 , xvector= 1 0 1 0
 5 ,     tmp= 1
 5 , xvector= 1 0 1 0 1
 6 ,     tmp= 1
 6 , xvector= 1 0 1 0 1 1
 7 ,     tmp= 0
 7 , xvector= 1 0 1 0 1 1 0
 8 ,     tmp= 0
 8 , xvector= 1 0 1 0 1 1 0 0
[1] "1" "0" "1" "0" "1"
"1" "0" "0"  <== what I want is
"unquoted" binary
values

on the other hand, similar, NOT-THE-SAME but related, "conversions"
are working,
e.g.
# seq = "1 0 0 1 0"
#> seq
# [1] "1 0 0 1 0"
#> strsplit(paste(seq), " ")
# [[1]]
# [1] "1" "0" "0" "1" "0"
#> paste(strsplit(paste(seq), " ")[[1]], collapse="")
# [1] "10010"
#       
#> seq=c(0,0,0,1,1,0,1)
#> seq
# [1] 0 0 0 1 1 0 1
#> paste(strsplit(paste(seq), " "), collapse="")
# [1] "0001101"

On Wed, 9 Dec 2009, brglez at ncsu.edu wrote:
> Full_Name: Franc Brglez
> Version: R 2.9.1 GUI 1.28 Tiger build 32-bit (5444)
> OS: MacOSX -- 10.6.2
> Submission from: (NULL) (24.148.163.114)
>
>
> I am demonstrating what may be a bug or my lack of experience. Please
review as
> it would help to hear from someone.
> MANY THANKS -- Franc Brglez
Please review the section 'BUGS' in the FAQ to work out why you have 
just annoyed the developers who will have to clear up after you.  You 
were asked only to use R-bugs when you 'know for certain', and only to 
report on current versions of R.

You started xvector as NULL: concatentating NULL and an object of 
noquote dispatches on the first argument, NULL, and uses the default 
method.  So xvector correctly does not have class "noquote". A simple 
way to do this would be

binS2binV <- function(string="0001101", sep="")
     noquote(strsplit(string, sep)[[1]])

or replace noquote by as.integer.

Note too the cat() and paste() print things differently, so using 
cat() to debug is not telling you anything useful about the eventual 
output.
>
> The function "binS2binV" returns what I consider a wrong value --
see the
> terminal output
>
> binS2binV = function(string="0001101", sep="")
> # this procedure is expected to convert a binary string to a binary vector
...
> # but does it?? Why do we get a vector with quoted binary values??
> {
>    qlist = strsplit(string, sep)
>    qvector = qlist[[1]]
>    cat("\n  string=", string)
>    cat("\n qvector=", qvector)
>    n = length(qvector) ; xvector = NULL
>    for (i in 1:n) {
> 	tmp = noquote(qvector[i])
> 	cat("\n", i,",     tmp=", tmp)
> 	xvector = c(xvector, tmp)
> 	cat("\n", i,", xvector=", xvector)
>    }
>    cat("\n")
>    return(xvector)
> }
>
>> print(binS2binV("10101100"))
>
>  string= 10101100
> qvector= 1 0 1 0 1 1 0 0
> 1 ,     tmp= 1
> 1 , xvector= 1
> 2 ,     tmp= 0
> 2 , xvector= 1 0
> 3 ,     tmp= 1
> 3 , xvector= 1 0 1
> 4 ,     tmp= 0
> 4 , xvector= 1 0 1 0
> 5 ,     tmp= 1
> 5 , xvector= 1 0 1 0 1
> 6 ,     tmp= 1
> 6 , xvector= 1 0 1 0 1 1
> 7 ,     tmp= 0
> 7 , xvector= 1 0 1 0 1 1 0
> 8 ,     tmp= 0
> 8 , xvector= 1 0 1 0 1 1 0 0
> [1] "1" "0" "1" "0" "1"
"1" "0" "0"  <== what I want is
"unquoted" binary
> values
>
> on the other hand, similar, NOT-THE-SAME but related,
"conversions" are working,
> e.g.
> # seq = "1 0 0 1 0"
> #> seq
> # [1] "1 0 0 1 0"
> #> strsplit(paste(seq), " ")
> # [[1]]
> # [1] "1" "0" "0" "1" "0"
> #> paste(strsplit(paste(seq), " ")[[1]],
collapse="")
> # [1] "10010"
> #
> #> seq=c(0,0,0,1,1,0,1)
> #> seq
> # [1] 0 0 0 1 1 0 1
> #> paste(strsplit(paste(seq), " "), collapse="")
> # [1] "0001101"
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595

brglez at ncsu.edu wrote:
> Full_Name: Franc Brglez
> Version: R 2.9.1 GUI 1.28 Tiger build 32-bit (5444)
> OS: MacOSX -- 10.6.2
> Submission from: (NULL) (24.148.163.114)
>
>
> I am demonstrating what may be a bug or my lack of experience. Please
review as
> it would help to hear from someone.
>   
It is your lack of experience.  Please do not abuse the bug reporting 
system.

Duncan Murdoch
> MANY THANKS -- Franc Brglez
>
> The function "binS2binV" returns what I consider a wrong value --
see the
> terminal output
>
> binS2binV = function(string="0001101", sep="") 
> # this procedure is expected to convert a binary string to a binary vector
...
> # but does it?? Why do we get a vector with quoted binary values??
> {   
>     qlist = strsplit(string, sep)
>     qvector = qlist[[1]]
>     cat("\n  string=", string)
>     cat("\n qvector=", qvector)
>     n = length(qvector) ; xvector = NULL
>     for (i in 1:n) {
> 	tmp = noquote(qvector[i])
> 	cat("\n", i,",     tmp=", tmp)
> 	xvector = c(xvector, tmp)
> 	cat("\n", i,", xvector=", xvector)
>     }
>     cat("\n")
>     return(xvector)
> }
>
>   
>> print(binS2binV("10101100"))
>>     
>
>   string= 10101100
>  qvector= 1 0 1 0 1 1 0 0
>  1 ,     tmp= 1
>  1 , xvector= 1
>  2 ,     tmp= 0
>  2 , xvector= 1 0
>  3 ,     tmp= 1
>  3 , xvector= 1 0 1
>  4 ,     tmp= 0
>  4 , xvector= 1 0 1 0
>  5 ,     tmp= 1
>  5 , xvector= 1 0 1 0 1
>  6 ,     tmp= 1
>  6 , xvector= 1 0 1 0 1 1
>  7 ,     tmp= 0
>  7 , xvector= 1 0 1 0 1 1 0
>  8 ,     tmp= 0
>  8 , xvector= 1 0 1 0 1 1 0 0
> [1] "1" "0" "1" "0" "1"
"1" "0" "0"  <== what I want is
"unquoted" binary
> values
>
> on the other hand, similar, NOT-THE-SAME but related,
"conversions" are working,
> e.g.
> # seq = "1 0 0 1 0"
> #> seq
> # [1] "1 0 0 1 0"
> #> strsplit(paste(seq), " ")
> # [[1]]
> # [1] "1" "0" "0" "1" "0"
> #> paste(strsplit(paste(seq), " ")[[1]],
collapse="")
> # [1] "10010"
> #       
> #> seq=c(0,0,0,1,1,0,1)
> #> seq
> # [1] 0 0 0 1 1 0 1
> #> paste(strsplit(paste(seq), " "), collapse="")
> # [1] "0001101"
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

Hello!
 
Please accept my sincere apologies for annoying the R development team with my
post this week. If I were required to register as "a developer" before
submission, this would not have happened. To rehabilitate myself, please find at
the bottom of this mail two R-functions, 'string2vector' and
'vector2string', with "comments and tests". Both functions may
go a long way towards assisting a number of R-users to make their R-programming
more productive. I am a novice R-programmer: I started dabbling in R less than
two months ago, heavily influenced by examples of code I see, including within
the R.org documents (monkey does what monkey sees). Before posting two
functions, I would really appreciate constructive edits where they may be needed
as well as their posting by someone-in-the-know so there will be conveniently
accessible for R users.

I am very impressed with potential of R and the community supporting it. I just
wish I got to R sooner: I am looking to R to better support my work in
"designed experiments to assess the statistically significant performance
of combinatorial optimization algorithms on instance isomorphs of NP-hard
problems" -- for better context of this mouthful, see the few postings
under
  http://www.cbl.ncsu.edu:16080/xBed/publications/
I am working on a tutorial paper where I expect R to play a significant role in
better explaining and illustrating, code-wise and graphically, the concepts
discussed in the publications above. I would welcome a co-author with experience
in R-programming as well as statistics and interests in the experimental methods
addressed in these publications.

As I elaborate in notes that follow, I was looking at a variety of
"R-documents" before my "bug" submission. I would appreciate
very much if some of you could take the time to scan through these notes and
respond briefly with useful pointers. Here are the headlines:

    (1) why I still think there may be a bug with 'noquote' vs
'as.integer'

    (2) search on "split string" and "join string"; the
missing package "stringr"

    (3) a take on "Tcl" commands 'split', 'join',
'string', 'append', 'foreach'

    (4) a take on "R" functions 'string2vector' and
'vector2string'

    (5) code and comments for "R" functions 'string2vector'
and 'vector2string

(1) why I still think there may be a bug with 'noquote' vs
'as.integer'
--------------------------------------------------------------------------------
> # MacOSX 10.6.2, R 2.9.1 GUI 1.28 Tiger build 32-bit (5444)
> qvector
[1] "0" "0" "0" "1" "1"
"0" "1"
> qvector[1]
[1] "0"
> tmp = noquote(qvector[1])
> tmp
[1] 0
> tmp = as.integer(qvector[1])
> tmp
[1] 0
> 
When embedded in the function as per my "bug" report,
'noquote' and 'as.integer' are no longer equivalent whereas in
the example above they appear to be equivalent!! I submitted the
"function" with print/cat statements for sake of illustration.

(2) search on "split string" and "join string"; the missing
package "stringr"
--------------------------------------------------------------------------------
http://search.r-project.org/ reveals
   orderof 850 messages for search on "split string"
   orderof 160 messages for search on "join string"

http://finzi.psych.upenn.edu/search.html reveals
    for search on "split string"
   	? Rhelp08:   [ split: 890 ] [ string: 1676 ] [ TOTAL: 77 ]
        ? functions: [ split: 954 ] [ string: 6453 ] [ TOTAL: 204 ]
    for search on "join string"
	? Rhelp08:   [ join: 176 ] [ string: 1676 ] [ TOTAL: 8 ]
	? functions: [ join: 192 ] [ string: 6453 ] [ TOTAL: 36 ]
    This site also provides a link to the package "stringr"
    http://finzi.psych.upenn.edu/R/library/stringr/html/00Index.html
However, the download does not deliver ...
> install.packages("stringr")
  ....
   package ?stringr? is not available

There are a lot of hard-to-understand and not-so-relevant code snippets in all
these 1000's of postings. I would argue that had robust functions such as
'string2vector' and 'vector2string' been included in the
R-package, many R-programmers could take longer vacations, spend their time more
productively,
and significantly reduce duplication of coding efforts on basically the same
problems.

Since vector is such and important "primitive" in R, I argue that
functions such as 'string2vector' and 'vector2string' should be
made to play a role similar to commands 'split', 'join',
'string', and 'append' that support programmers in Tcl. See my
take on Tcl in the section below.

(3) a take on "Tcl" commands 'split', 'join',
'string', 'append', 'foreach'
--------------------------------------------------------------------------------
I have been using Tcl to "wrap" a number of combinatorial solvers and
automate workflows that implement and execute a number of my experiments on
instance isomorphs. I even used Tcl to prototype few combinatorial optimization
algorithm prototypes and write code for statistical analysis -- as task for
which I now find R much better suited.

I intend to alert my Tcl colleagues in-the-know about the wonderful
infrastructure provided in R when it comes to the R-shell (at least under
MacOSX), and the ability to name and initialize function variable defaults
explicitly, and the ability to install new packages so transparently. Before
coming across R, I already took the trouble to create Tcl wrapper programs with
command lines that feature identical order-indepent syntax as the syntax used in
R. This being said, what I miss about R is gathering all commands on a single
page such as
   http://www.tcl.tk/man/tcl8.5/TclCmd/contents.htm
Note that once you click on any of the commands, a number of classes that extend
each command become visible, including the example section(s).

Here I illustrate my use of just five tcl commands that subsequently guided my
"design" of the function 'string2vector' in
'vector2string' "R"

# few "Tcl" examples before designing the function
'string2vector' in "R"
% set binS "10011"
% join [split $binS ""] ", "
1, 0, 0, 1, 1
%
% set strS "I \t am\tdone" 
% foreach item [split $strS "\t"] {append strSQ \"$item\",}
% set strSQ [string trimright $strSQ ,]
"I "," am","done"
# 
# few "Tcl" examples before designing the function
'vector2string' in "R"
% set strV "1,0,0,1"
1,0,0,1
% split $strV ","
1 0 0 1
join [split $strV ","] ":"
1:0:0:1

(4) a take on "R" functions 'string2vector' and
'vector2string'
--------------------------------------------------------------------------------
> # few tests of the function 'string2vector' in "R"
> binS = "10011"
> binV = string2vector(binS, SS="", type="int")
> binV[2] ; binV[5]
[1] 0
[1] 1
> strS = "I am done" 
> vecS = string2vector(strS, SS=" ", type="char")
> vecS[1] ; vecS[3]
[1] "I"
[1] "done"
> 
> # few tests of the function 'vector2string' in "R"
> binV = c(1,0,0,1) 
> vector2string(binV, type="int")
[1] "1001"
> vector2string(binV, SS=" ", type="char")
[1] "1 0 0 1"
> subsV = c("I", "am", "done")  
> vector2string(subsV, SS=":", type="char")
[1] "I:am:done"
> 
(5) code and comments for "R" functions 'string2vector' and
'vector2string'
--------------------------------------------------------------------------------

string2vector = function(string="ch-2 \t sec-7\tex-5",
SS="\t", type="char")
#
# This procedure splits a string and assigns substrings to an R-vector.
# The split is controlled by the string separator SS (default value: 
SS="\t").
# Here we convert  a binary string into a binary vector:
#   let  binS = "10011"  
#   then binV = string2vector(binS, SS="", type="int")
# Here we convert a string into a vector of substrings:
#   let  strS = "I am done" 
#   then vecS = string2vector(strS, SS=" ", type="char")
#
# LIMITATION: The function interprets all substrings either as of type 
#             "int" or "char".  A function that interprets
the type of each
#             substring dynamically may one day be written by an R-guru.
#              
# Franc Brglez, Wed Dec  9 14:19:16 EST 2009
{   
    qlist   = strsplit(string, SS) ; qvector = qlist[[1]]
    n = length(qvector) ; xvector = NULL
    for (i in 1:n) {
        if (type == "int") {
            tmp = as.integer(qvector[i])
        } else {
            tmp = qvector[i]
        }
	xvector = c(xvector, tmp)
    }
    return(xvector)
} # string2vector

vector2string = function(vector=c("ch-2", "sec-7",
"ex-5"), SS="_", type="char")
#
# This procedure converts values from a vector to a concatenation of substrings 
# separated by user-specified string separator SS (default value: 
SS="_").
# Each substring represents a vector component value, either as a numerical 
# value or as an alphanumeric string. 
# Here we convert a binary vector to a binary string representing an integer:
#   let  binV = c(1,0,0,1)  
#   then strS = vector2string(binV, type="int")
# Here we convert a binary vector to string representing a binary sequence:
#   let  binV = c(1,0,0,1)  
#   then seqS = vector2string(binV, SS=" ", type="char")
# Here we convert a vector of substrings to colon-separated string:
#   let subsV = c("I", "am", "done")  
#   then strS = vector2string(subsV, SS=":", type="char")
#
# LIMITATION: The function interprets all substrings in the vector either as of 
#             type "int" or "char".  A function that
interprets the type of each
#             substring dynamically may one day be written by an R-guru.
#
# Franc Brglez, Wed Dec  9 15:43:59 EST 2009
{   
    if (type == "int") {
        string = paste(strsplit(paste(vector), " "),
collapse="")
    } else {
        n = length(vector) ; nm1 = n-1 ; string = ""
        for (i in 1:nm1) {
            tmp    = noquote(vector[i])
            string = paste(string, tmp, SS, sep="")
        }
        tmp    = noquote(vector[n])
        string = paste(string, tmp, sep="")     
    }
    return(string)
} # vector2string

----------------
Dr. Franc Brglez                                        email: brglez at
ncsu.edu
Department of Computer Science, Box 8206     http://sitta.csc.ncsu.edu/~brglez
North Carolina State University                            TEL: (919) 515-9675
Raleigh NC 27695-8206 USA

Just responding to some of the issues in this long post:

(1) Don't rely on the printed form of an object to decide whether or not 
they are identical.  The function str() is very useful in this regard, 
and sometimes also unclass().  To see whether two object are identical, 
use the function identical()

 > qvector <- c("0", "0", "0",
"1", "1", "0", "1")
 > qvector[1]
[1] "0"
 > noquote(qvector[1])
[1] 0
 > str(noquote(qvector[1]))
Class 'noquote'  chr "0"
 > as.integer(qvector[1])
[1] 0
 > str(as.integer(qvector[1]))
 int 0
 > identical(noquote(qvector[1]), as.integer(qvector[1]))
[1] FALSE
 >

Does this alleviate the concern as to the possibility of a bug in 
noquote/as.integer? Or were there deeper issues?

(2) to see how some other users of R have package up miscellaneous 
functions that might be of use to other people, look for packages on 
CRAN with "misc" in their names -- I see almost 10 of them.  The
problem
with just posting snippets of code is that they get lost in all the 
other posts here, and many long term R users have dozens if not hundreds 
of their own functions that are streamlined for their own frequent tasks 
and style of programming.

(3) sounds like a great idea to use R to bring statistical rigor into 
the analysis of the performance of combinatorial optimization algorithms!

(4) install.packages("stringr") works fine for me.  Maybe it was a 
temporary glitch?  Have you checked whether you have a valid repository 
selected?  E.g., I have in my .Rprofile:
options(repos=c(CRAN="http://cran.cnr.Berkeley.edu" , 
CRANextra="http://www.stats.ox.ac.uk/pub/RWin"))

Enjoy learning R!

-- Tony Plate

Franc Brglez wrote:
> Hello!
>  
> Please accept my sincere apologies for annoying the R development team with
my post this week. If I were required to register as "a developer"
before submission, this would not have happened. To rehabilitate myself, please
find at the bottom of this mail two R-functions, 'string2vector' and
'vector2string', with "comments and tests". Both functions may
go a long way towards assisting a number of R-users to make their R-programming
more productive. I am a novice R-programmer: I started dabbling in R less than
two months ago, heavily influenced by examples of code I see, including within
the R.org documents (monkey does what monkey sees). Before posting two
functions, I would really appreciate constructive edits where they may be needed
as well as their posting by someone-in-the-know so there will be conveniently
accessible for R users.
>
> I am very impressed with potential of R and the community supporting it. I
just wish I got to R sooner: I am looking to R to better support my work in
"designed experiments to assess the statistically significant performance
of combinatorial optimization algorithms on instance isomorphs of NP-hard
problems" -- for better context of this mouthful, see the few postings
under
>   http://www.cbl.ncsu.edu:16080/xBed/publications/
> I am working on a tutorial paper where I expect R to play a significant
role in better explaining and illustrating, code-wise and graphically, the
concepts discussed in the publications above. I would welcome a co-author with
experience in R-programming as well as statistics and interests in the
experimental methods addressed in these publications.
>
> As I elaborate in notes that follow, I was looking at a variety of
"R-documents" before my "bug" submission. I would appreciate
very much if some of you could take the time to scan through these notes and
respond briefly with useful pointers. Here are the headlines:
>
>     (1) why I still think there may be a bug with 'noquote' vs
'as.integer'
>
>     (2) search on "split string" and "join string"; the
missing package "stringr"
>
>     (3) a take on "Tcl" commands 'split', 'join',
'string', 'append', 'foreach'
>
>     (4) a take on "R" functions 'string2vector' and
'vector2string'
>
>     (5) code and comments for "R" functions
'string2vector' and 'vector2string
>
> (1) why I still think there may be a bug with 'noquote' vs
'as.integer'
>
--------------------------------------------------------------------------------
>   
>> # MacOSX 10.6.2, R 2.9.1 GUI 1.28 Tiger build 32-bit (5444)
>> qvector
>>     
> [1] "0" "0" "0" "1" "1"
"0" "1"
>   
>> qvector[1]
>>     
> [1] "0"
>   
>> tmp = noquote(qvector[1])
>> tmp
>>     
> [1] 0
>   
>> tmp = as.integer(qvector[1])
>> tmp
>>     
> [1] 0
>   
> When embedded in the function as per my "bug" report,
'noquote' and 'as.integer' are no longer equivalent whereas in
the example above they appear to be equivalent!! I submitted the
"function" with print/cat statements for sake of illustration.
>
> (2) search on "split string" and "join string"; the
missing package "stringr"
>
--------------------------------------------------------------------------------
> http://search.r-project.org/ reveals
>    orderof 850 messages for search on "split string"
>    orderof 160 messages for search on "join string"
>
> http://finzi.psych.upenn.edu/search.html reveals
>     for search on "split string"
>    	? Rhelp08:   [ split: 890 ] [ string: 1676 ] [ TOTAL: 77 ]
>         ? functions: [ split: 954 ] [ string: 6453 ] [ TOTAL: 204 ]
>     for search on "join string"
> 	? Rhelp08:   [ join: 176 ] [ string: 1676 ] [ TOTAL: 8 ]
> 	? functions: [ join: 192 ] [ string: 6453 ] [ TOTAL: 36 ]
>     This site also provides a link to the package "stringr"
>     http://finzi.psych.upenn.edu/R/library/stringr/html/00Index.html
> However, the download does not deliver ...
>   
>> install.packages("stringr")
>>     
>   ....
>    package ?stringr? is not available
>
> There are a lot of hard-to-understand and not-so-relevant code snippets in
all these 1000's of postings. I would argue that had robust functions such
as 'string2vector' and 'vector2string' been included in the
R-package, many R-programmers could take longer vacations, spend their time more
productively,
> and significantly reduce duplication of coding efforts on basically the
same
> problems.
>
> Since vector is such and important "primitive" in R, I argue that
functions such as 'string2vector' and 'vector2string' should be
made to play a role similar to commands 'split', 'join',
'string', and 'append' that support programmers in Tcl. See my
take on Tcl in the section below.
>
> (3) a take on "Tcl" commands 'split', 'join',
'string', 'append', 'foreach'
>
--------------------------------------------------------------------------------
> I have been using Tcl to "wrap" a number of combinatorial solvers
and automate workflows that implement and execute a number of my experiments on
instance isomorphs. I even used Tcl to prototype few combinatorial optimization
algorithm prototypes and write code for statistical analysis -- as task for
which I now find R much better suited.
>
> I intend to alert my Tcl colleagues in-the-know about the wonderful
infrastructure provided in R when it comes to the R-shell (at least under
MacOSX), and the ability to name and initialize function variable defaults
explicitly, and the ability to install new packages so transparently. Before
coming across R, I already took the trouble to create Tcl wrapper programs with
command lines that feature identical order-indepent syntax as the syntax used in
R. This being said, what I miss about R is gathering all commands on a single
page such as
>    http://www.tcl.tk/man/tcl8.5/TclCmd/contents.htm
> Note that once you click on any of the commands, a number of classes that
extend each command become visible, including the example section(s).
>
> Here I illustrate my use of just five tcl commands that subsequently guided
my "design" of the function 'string2vector' in
'vector2string' "R"
>
> # few "Tcl" examples before designing the function
'string2vector' in "R"
> % set binS "10011"
> % join [split $binS ""] ", "
> 1, 0, 0, 1, 1
> %
> % set strS "I \t am\tdone" 
> % foreach item [split $strS "\t"] {append strSQ
\"$item\",}
> % set strSQ [string trimright $strSQ ,]
> "I "," am","done"
> # 
> # few "Tcl" examples before designing the function
'vector2string' in "R"
> % set strV "1,0,0,1"
> 1,0,0,1
> % split $strV ","
> 1 0 0 1
> join [split $strV ","] ":"
> 1:0:0:1
>
> (4) a take on "R" functions 'string2vector' and
'vector2string'
>
--------------------------------------------------------------------------------
>   
>> # few tests of the function 'string2vector' in "R"
>> binS = "10011"
>> binV = string2vector(binS, SS="", type="int")
>> binV[2] ; binV[5]
>>     
> [1] 0
> [1] 1
>   
>> strS = "I am done" 
>> vecS = string2vector(strS, SS=" ", type="char")
>> vecS[1] ; vecS[3]
>>     
> [1] "I"
> [1] "done"
>   
>> # few tests of the function 'vector2string' in "R"
>> binV = c(1,0,0,1) 
>> vector2string(binV, type="int")
>>     
> [1] "1001"
>   
>> vector2string(binV, SS=" ", type="char")
>>     
> [1] "1 0 0 1"
>   
>> subsV = c("I", "am", "done")  
>> vector2string(subsV, SS=":", type="char")
>>     
> [1] "I:am:done"
>   
>
> (5) code and comments for "R" functions 'string2vector'
and 'vector2string'
>
--------------------------------------------------------------------------------
>
> string2vector = function(string="ch-2 \t sec-7\tex-5",
SS="\t", type="char")
> #
> # This procedure splits a string and assigns substrings to an R-vector.
> # The split is controlled by the string separator SS (default value: 
SS="\t").
> # Here we convert  a binary string into a binary vector:
> #   let  binS = "10011"  
> #   then binV = string2vector(binS, SS="", type="int")
> # Here we convert a string into a vector of substrings:
> #   let  strS = "I am done" 
> #   then vecS = string2vector(strS, SS=" ",
type="char")
> #
> # LIMITATION: The function interprets all substrings either as of type 
> #             "int" or "char".  A function that
interprets the type of each
> #             substring dynamically may one day be written by an R-guru.
> #              
> # Franc Brglez, Wed Dec  9 14:19:16 EST 2009
> {   
>     qlist   = strsplit(string, SS) ; qvector = qlist[[1]]
>     n = length(qvector) ; xvector = NULL
>     for (i in 1:n) {
>         if (type == "int") {
>             tmp = as.integer(qvector[i])
>         } else {
>             tmp = qvector[i]
>         }
> 	xvector = c(xvector, tmp)
>     }
>     return(xvector)
> } # string2vector
>
> vector2string = function(vector=c("ch-2", "sec-7",
"ex-5"), SS="_", type="char")
> #
> # This procedure converts values from a vector to a concatenation of
substrings
> # separated by user-specified string separator SS (default value: 
SS="_").
> # Each substring represents a vector component value, either as a numerical
> # value or as an alphanumeric string. 
> # Here we convert a binary vector to a binary string representing an
integer:
> #   let  binV = c(1,0,0,1)  
> #   then strS = vector2string(binV, type="int")
> # Here we convert a binary vector to string representing a binary sequence:
> #   let  binV = c(1,0,0,1)  
> #   then seqS = vector2string(binV, SS=" ",
type="char")
> # Here we convert a vector of substrings to colon-separated string:
> #   let subsV = c("I", "am", "done")  
> #   then strS = vector2string(subsV, SS=":",
type="char")
> #
> # LIMITATION: The function interprets all substrings in the vector either
as of
> #             type "int" or "char".  A function that
interprets the type of each
> #             substring dynamically may one day be written by an R-guru.
> #
> # Franc Brglez, Wed Dec  9 15:43:59 EST 2009
> {   
>     if (type == "int") {
>         string = paste(strsplit(paste(vector), " "),
collapse="")
>     } else {
>         n = length(vector) ; nm1 = n-1 ; string = ""
>         for (i in 1:nm1) {
>             tmp    = noquote(vector[i])
>             string = paste(string, tmp, SS, sep="")
>         }
>         tmp    = noquote(vector[n])
>         string = paste(string, tmp, sep="")     
>     }
>     return(string)
> } # vector2string
>
> ----------------
> Dr. Franc Brglez                                        email: brglez at
ncsu.edu
> Department of Computer Science, Box 8206    
http://sitta.csc.ncsu.edu/~brglez
> North Carolina State University                            TEL: (919)
515-9675
> Raleigh NC 27695-8206 USA  
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>
>