I'll admit that I cut my teeth on ASCII, but I worried about your
reliance on that ancient typographic ordering. I wrote a little
function:
al2num_sub<-function(x) {
xspl<-unlist(strsplit(x,""))
if(length(xspl) > 1)
xspl<-paste(xspl[1],which(letters==xspl[2]),sep=".")
return(xspl)
}
unlist(sa
On Sat, Jul 11, 2020 at 8:04 AM Fox, John wrote:
> We've had several solutions, and I was curious about their relative
> efficiency. Here's a test
Am I the only person on this mailing list who learnt to program with ASCII...?
In theory, the most ***efficient*** solution, is to get the
ASCII/UTF
It might be easier to simply assign names to the numeric vector if you
already have numeric and character vectors of the right lengths. Using
Heibergers's vectors:
xc <- c("1", "1a", "1b", "1c", "2", "2a", "2b", "2c")
xn <- c(1, 1.3, 1.5, 1.7, 2, 2.3, 2.5, 2.7)
names(xn) <- xc
testdata <- r
ave had enough solutions and methods posted but there are likely
many more as there is rarely only one way to do things in R.
-----Original Message-
From: R-help On Behalf Of Richard O'Keefe
Sent: Saturday, July 11, 2020 3:02 AM
To: Eric Berger
Cc: Jean-Louis Abitbol ; R Project Help
Agreed, I meant to add this line (for unclassed factor levels 1-through-8):
> ((1:8 - 1)*(0.25))+1
[1] 1.00 1.25 1.50 1.75 2.00 2.25 2.50 2.75
Depending on the circumstance, you can also consider using dummy
factors or even "NA" as a level; see the "factor" help page for
details.
Best, Bill.
W.
Hello Bill,
Thanks.
That has indeed the advantage of keeping the histology classification on the
plot instead of some arbitrary numeric scale.
Best wishes, JL
On Sat, Jul 11, 2020, at 8:25 AM, William Michels wrote:
> Hello Jean-Louis,
>
> Noting the subject line of your post I thought the f
The string index approach works with any mapping from stage names
to stage numbers, not just regular ones. For example, if we had
"1" -> 1, "1a" -> 1.4, "1b" -> 1.6
"2" -> 2, "2a" -> 2.3, "2b" -> 2.7
the 'sub' version would fail miserably while the string index
version would just work. The 'sub'
Hello Jean-Louis,
Noting the subject line of your post I thought the first answer would
have been encoding histology stages as factors, and "unclass-ing" them
to obtain integers that then can be mathematically manipulated. You
can get a lot of work done with all the commands listed on the
"factor"
xn <- as.numeric(sub("c",".7",sub("b",".5",sub("a",".3",xc
On Sat, Jul 11, 2020 at 5:09 AM Richard O'Keefe wrote:
> This can be done very simply because vectors in R can have
> named elements, and can be indexed by strings.
>
> > stage <- c("1" = 1, "1a" = 1.3, "1b" = 1.5, "1c" = 1.7,
> +
This can be done very simply because vectors in R can have
named elements, and can be indexed by strings.
> stage <- c("1" = 1, "1a" = 1.3, "1b" = 1.5, "1c" = 1.7,
+"2" = 2, "2a" = 2.3, "2b" = 2.5, "2c" = 2.7,
+"3" = 3, "3a" = 3.3, "3b" = 3.5, "3c" = 3.7)
> testdata <- rep
Many thanks to all. This help-list is wonderful.
I have used Rich Heiberger solution using match and found something to learn in
each answer.
off topic, I also enjoyed very much his 2008 paper on the graphical
presentation of safety data
Best wishes.
On Fri, Jul 10, 2020, at 10:02 PM, F
Thanks! As I said, cute exercise.
Best,
Bert
On Fri, Jul 10, 2020 at 1:21 PM Fox, John wrote:
> Dear Bert,
>
> Wouldn't you know it, but your contribution arrived just after I pressed
> "send" on my last message? So here's how your solution compares:
>
> > microbenchmark(John = John <- xn[x]
Dear Bert,
Wouldn't you know it, but your contribution arrived just after I pressed "send"
on my last message? So here's how your solution compares:
> microbenchmark(John = John <- xn[x],
+Rich = Rich <- xn[match(x, xc)],
+Jeff = Jeff <- {
+ n
Hi,
We've had several solutions, and I was curious about their relative efficiency.
Here's a test with a moderately large data vector:
> library("microbenchmark")
> set.seed(123) # for reproducibility
> x <- sample(xc, 1e4, replace=TRUE) # "data"
> microbenchmark(John = John <- xn[x],
+
... and continuing with this cute little thread...
I found the OP's specification a little imprecise -- are your values always
a string that begins with *some sort" of numeric value followed by "some
sort" of alpha code? That is, could the numeric value be several digits and
the alpha code several
Here is a different approach:
xc <- c("1", "1a", "1b", "1c", "2", "2a", "2b", "2c")
xn <- as.numeric(gsub("a", ".3", gsub("b", ".5", gsub("c", ".7", xc
xn
# [1] 1.0 1.3 1.5 1.7 2.0 2.3 2.5 2.7
David L Carlson
Professor Emeritus of Anthropology
Texas A&M University
On Fri, Jul 10, 2020 at 1:
Obvious is in the eye of the beholder. Presuming your letters don't go beyond
"i":
a) Lookup table:
tbl <- read.table( text=
"OldCode NewCode
1 1
1a1.1
1b1.2
1c1.3
2 2
2a2.1
2b2.2
", as.is=TRUE, header=TRUE )
tblv <- setNames( tbl$NewCode
Dear Jean-Louis,
There must be many ways to do this. Here's one simple way (with no claim of
optimality!):
> xc <- c("1", "1a", "1b", "1c", "2", "2a", "2b", "2c")
> xn <- c(1, 1.3, 1.5, 1.7, 2, 2.3, 2.5, 2.7)
>
> set.seed(123) # for reproducibility
> x <- sample(xc, 20, replace=TRUE) # "data"
Dear All
I have a character vector, representing histology stages, such as for example:
xc <- c("1", "1a", "1b", "1c", "2", "2a", "2b", "2c")
and this goes on to 3, 3a etc in various order for each patient. I do have of
course a pre-established classification available which does change accor
19 matches
Mail list logo
