R devel - Nov 1998 - Proposal for discussion: COLNAMES & ROWNAMES

Looking into several different parts of  R../src/library/base/R/*.R
has led me to the conclusion
that quite a bit of code doubling could be saved by using the following two
functions whose naming philosophy is derived from that of  NROW() & NCOL():

  COLNAMES <- function(x)
      if(is.null(n <- colnames(x))) paste(seq(length=NCOL(x))) else n
  ROWNAMES <- function(x)
      if(is.null(n <- rownames(x))) paste(seq(length=NCOL(x))) else n

Do you have any positive or negative thoughts on this?
[a negative one that I had: ``yet another set of such *names functions
!'']
Maybe, replying only to me -- who then would summarize -- is okay.

Martin
Maechler <maechler@stat.math.ethz.ch>	http://stat.ethz.ch/~maechler/
Seminar fuer Statistik, ETH-Zentrum SOL G1;	Sonneggstr.33
ETH (Federal Inst. Technology)	8092 Zurich	SWITZERLAND
phone: x-41-1-632-3408		fax: ...-1086			<><
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To:
r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._

>>>>> "PaulG" == Paul Gilbert
<pgilbert@bank-banque-canada.ca> writes:
    MM> COLNAMES <- function(x)
    MM>      if(is.null(n <- colnames(x))) paste(seq(length=NCOL(x))) else
n
    MM> ROWNAMES <- function(x)
    MM>      if(is.null(n <- rownames(x))) paste(seq(length=NCOL(x))) else
n

    MM> Do you have any positive or negative thoughts on this?

    PaulG> Here are a few thoughts.

thank you!

    PaulG> 0/ In ROWNAMES use NROW

oh yes !

    PaulG> 1/ You might try do this in some way that generalizes more
    PaulG> easily to arrays, but I'm not sure how.

this would mean DIMNAMES, presumably.

    PaulG> 2/ You might want paste("col", seq(length=NCOL(x)))
instead of
    PaulG> just the numbers.

Not directly;
    In the places I've seen a possible use, 
    sometimes there was "var", sometimes "..." (forgotten),
sometimes no
    prefix at all.  

However, we could add an optional argument `prefix', 
even with sensible defaults: 

    COLNAMES <- function(x, prefix = "col")
	if(is.null(n <- colnames(x)))
		paste(prefix, seq(length=NCOL(x)), sep="") else n
    ROWNAMES <- function(x, prefix = "row")
	if(is.null(n <- rownames(x)))
		paste(prefix, seq(length=NROW(x)), sep="") else n
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To:
r-devel-request@stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._