extendrange(): suggested improvement
Marius Hofert <marius.hofert at uwaterloo.ca>
on Wed, 25 Apr 2018 17:31:01 -0400 writes:
> Hi,
> I often need to extend the plot range to the right, but not to the
> left (for example: not below 0 so that log = "x" still works...). This
> could be a handy improvement of extendrange():
--- utils.R 2015-08-25 18:18:20.000000000 -0400
+++ utils.R 2018-04-25 17:21:25.000000000 -0400
@@ -30,6 +30,6 @@
## Purpose: extend a range by a factor 'f' - on each side
if(!missing(r) && length(r) != 2)
stop("'r' must be a \"range\", hence of length 2")
- r + c(-f,f) * diff(r)
-
+ if(length(f) == 1) f <- rep(f, 2)
+ r + c(-f[1], f[2]) * diff(r)
}
Yes, you are right and it's not the first time I've heard/seen
this wish.
Thank you for the suggestion!
I'd go for the more elegant (faster, at least in default case?)
version
extendrange <- function(x, r = range(x, na.rm = TRUE), f = 0.05)
{
## Purpose: extend a range by a factor 'f' - on each side
if(!missing(r) && length(r) != 2)
stop("'r' must be a \"range\", hence of length 2")
f <- if(length(f) == 1L) c(-f,f) else c(-f[1L], f[2L])
r + f * diff(r)
}
PS:
/* I hope the tidy faction will at some time be convinced that
using if() as a *function* in R is elegant and *the* R-way:
R is as functional a language as possible and hereby differs
from C and similar languages !
*/
Martin Maechler
ETH Zurich