position
Find or assign the implied position for graphing the levels of a factor. A new class "positioned", which inherits from "ordered" and "factor", is defined.
The default values for plotting a factor x
are the integers
1:length(levels(x))
. These functions provide a way of
specifying alternate plotting locations for the levels.
- Keywords
- dplot
Usage
position(x)position(x) <- value
## S3 method for class 'positioned':
is.numeric(x, ...)
## S3 method for class 'positioned':
as.numeric(x, ...)
## S3 method for class 'positioned':
[(x, ..., drop=FALSE)
## S3 method for class 'positioned':
is.na(x)
as.positioned(x)
as.position(x)
is.positioned(x)
positioned(x, ..., value)
## S3 method for class 'positioned':
print(x, ...)
## S3 method for class 'positioned':
unique(x, incomparables = FALSE, ...)
unpositioned(x, ...)
Arguments
- x
- numeric vector or factor
- value
- numerical values to be
associated with
levels(x)
. Thelength(value)
must equallength(levels(as.factor(x)))
. - ...
- other arguments.
- drop
- See#ifndef S-Plus
Extract
. #endif #ifdef S-PlusSubscript
. #endif - incomparables
- See#ifndef S-Plus
unique
. #endif #ifdef S-Plusunique
. #endif
Value
position(x) <- value
first forces its argument to be an ordered factor and then assigns thevalue
to the"position"
attribute of the ordered factor. The result is assigned class"positioned"
and returned.position(x)
returns the position values associated withlevels(x)
. Ifx
is a positioned factor, then the"position"
attribute is returned. Ifx
is a factor, then the integers1:length(levels(x))
are returned. For anything else,as.numeric(x)
is returned.as.position(x)
returns a numeric vector the length of the original vector. Ifx
inherits from"factor"
, then the values in the vector are the values inposition(x)
subscripted by the levels of the factor. Ifx
is numeric, thenx
itself is returned.unpositioned(x)
removes the"position"
attribute and removes the"positioned"
value from the theoldClass
of the object.
See Also
panel.interaction2wt
,#ifndef S-Plus
factor
.
#endif
#ifdef S-Plus
factor
.
#endif
Examples
## ordered with character levels defaults to
## integer position of specified levels
tmp <- ordered(c("mm","cm","m","m","mm","cm"),
levels=c("mm","cm","m")) ## size order
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## position is assigned to ordered in specified order
tmp <- ordered(c("cm","mm","m","m","mm","cm"),
levels=c("mm","cm","m")) ## size order
levels(tmp)
position(tmp) <- c(-3, -2, 0) ## log10 assigned in size order
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## numeric stays numeric
tmp <- c(0.010, 0.001, 1.000, 1.000, 0.001, 0.010)
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## factor with numeric levels, position is integer position in size order
tmp <- factor(c(0.010, 0.001, 1.000, 1.000, 0.001, 0.010))
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## ordered with numeric levels, position is numeric value in size order
tmp <- ordered(c(0.010, 0.001, 1.000, 1.000, 0.001, 0.010))
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## factor with numeric levels
## position is assigned in size order
tmp <- factor(c(0.010, 0.001, 1.000, 1.000, 0.001, 0.010))
levels(tmp)
position(tmp) <- c(-3, -2, 0) ## log10 assigned in size order
tmp
as.numeric(tmp)
levels(tmp)
position(tmp)
as.position(tmp)
as.positioned(tmp)
positioned(tmp)
unpositioned(tmp)
unique(tmp)
## boxplots coded by week
tmp <- data.frame(Y=rnorm(40, rep(c(20,25,15,22), 10), 5),
week=ordered(rep(1:4, 10)))
position(tmp$week) <- c(1, 2, 4, 8)
if.R(r=
bwplot(Y ~ week, horizontal=FALSE,
scales=list(x=list(limits=c(0,9),
at=position(tmp$week),
labels=position(tmp$week))),
data=tmp, panel=panel.bwplot.intermediate.hh)
,s=
t(bwplot(week ~ Y, at=position(tmp$week),
scales=list(y=list(limits=c(0,9),
at=position(tmp$week), labels=position(tmp$week))),
data=tmp, panel=panel.bwplot.intermediate.hh))
)
#### You probably don't want to use the next two examples.
#### You need to be aware of their behavior.
##
## factor with character levels defaults to
## integer position of sorted levels.
## you probably DON'T want to do this!
tmp <- factor(c("cm","mm","m","m","mm","cm")) ## default alphabetic order
tmp
as.numeric(tmp)
levels(tmp) ## you probably DON'T want to do this!
position(tmp) ## you probably DON'T want to do this!
as.numeric(tmp)
##
## position is assigned to factor in default alphabetic order.
## you probably DON'T want to do this!
tmp <- factor(c("cm","mm","m","m","mm","cm"))
levels(tmp)
position(tmp) <- c(-3, -2, 0) ## assigned in default alphabetic order
tmp
as.numeric(tmp)
levels(tmp) ## you probably DON'T want to do this!
position(tmp) ## you probably DON'T want to do this!
as.numeric(tmp)