Displaying 20 results from an estimated 8000 matches similar to: "removing elements from a "unit" vector"
2008 Jun 27
1
include S4 class and methods in a package
DeaR list,
Pardon the stupidity of this question but I've been trying this for a
while now without success.
I've followed the example given in the green book "programming with
data", and I now have a working example of a S4 class with a few
methods (plot, summary, as.data.frame). It's all very nice in one
file, but I cannot find the way to put this information in a
2009 Sep 24
1
unexpected behavior of `[<-` method for class unit.arithmetic
Dear list,
Consider the following,
library(grid)
w = unit.c(unit(1, "in"), unit(2, "in"))
w2 = w + unit(1, "mm")
w[2] <- 0
w2[2] <- 0
convertUnit(w, "mm")
#[1] 25.4mm 0mm
convertUnit(w2, "mm")
#Error in grid.Call("L_convert", x, as.integer(whatfrom),
as.integer(whatto), :
# INTEGER() can only be applied to a
2011 Feb 15
1
gList and gTree methods of grid::grobX
Dear all,
In an attempt to draw fill patterns in grid graphics, I have
encountered a behavior of grobX that I cannot understand from the
documentation. Consider this,
library(grid)
## gTree
g1 <- gTree(children=gList(
rectGrob(0.5,0.5, width=unit(0.8,"npc"),
height=unit(2,"cm")),
circleGrob(r=0.3)), vp=viewport(0.5,0.5))
##
2007 Dec 28
1
unit attribute to list elements
Hi,
I've started my own (first) package, part of which consists in
listing common physical constants (Planck's constant, the speed of
light in vacuum, etc). I'm wondering what would be a good way of
dealing with pairs of value/unit.
> constants <- list( cel = 2.99792458e8 , #m/s
> Z0 = 376.730313461, #ohm
> eps0 = 8.854187817e-12,#F/m
> mu0 = 4*pi*1e-7,#N/A^2
2010 May 18
1
lattice::panel.levelplot.raster too picky with unequal spacing
Dear all,
I got a couple of warnings using panel.levelplot.raster,
In panel.levelplot.raster(..., interpolate = TRUE) :
'y' values are not equispaced; output will be wrong
although I was quite sure my data were equally spaced (indeed, I
created them with seq()). A closer look at the source code reveals
that the function tests for exact uniformity in grid spacing,
if
2010 Mar 19
2
lattice grob
Dear list,
I'm trying to arrange various grid objects on a page using a
frameGrob. It works fine with basic grobs (textGrob, gTree, etc.), and
also with ggplot2 objects using the ggplotGrob() function. I am
however stuck with lattice. As far as I understand, lattice produces a
list of class trellis, which is eventually displayed using the
plot.trellis method. I am not sure if/how one can
2010 Apr 17
2
grid.cap() requires more time?
Dear all,
I am puzzled by the following behavior of the new grid.cap() function,
which appears to run out of time when capturing the output of a
graphic. It works fine if I introduce a Sys.sleep(1) before executing
more code,
library(grid)
quartz()
grid.circle(gp=gpar(fill="black"))
gg <- grid.cap()
dev.new()
grid.raster(gg) ## completely blank
gg[gg!="white"] ## indeed
2009 Sep 02
2
combining grid.text, expression and variables
Dear R-users,
I am trying to use the grid.text and expression functions to display
several character strings and plotmath text on a viewport. Some strings
can include a variable portion (PI.limits in the following example),
which I thought could be implemented by combining the bquote and the
expression functions. Unfortunately, my expressions do not seem to be
evaluated. I would greatly
2009 Dec 20
1
basic proto question
Dear list,
I made the following example of a proto object that contains some data
and a spline interpolation. I don't understand why test$predict()
fails with this error message:
Error: evaluation nested too deeply: infinite recursion / options(expressions=)?
Best regards,
baptiste
test <- proto(source = data.frame(x=1:10, y=rnorm(10)),
raw = function(.){
2010 Oct 01
2
strange interaction between rasterImage and Grid graphics
Dear all,
This may be specific to Mac, I haven't had a chance to test another
platform. Consider this,
plot(1,1,t="n")
rasterImage(matrix(1),1,1,1,1)
library(grid)
grid.rect(gp=gpar(fill="grey"))
The grid.rect covers the full device window as expected. However, when
I resize the window ever so slightly (interactive device) the rectGrob
is suddenly clipped to the previous
2010 Sep 09
1
scalable < > delimiters in plotmath
Dear list,
I read in ?plotmath that I can use bgroup to draw scalable delimiters
such as [ ] and ( ). The same technique fails with < > however, and I
cannot find a workaround,
grid.text(expression(bgroup("<",atop(x,y),">")))
Error in bgroup("<", atop(x, y), ">") : invalid group delimiter
Regards,
baptiste
sessionInfo()
R version
2010 Sep 09
1
scalable < > delimiters in plotmath
Dear list,
I read in ?plotmath that I can use bgroup to draw scalable delimiters
such as [ ] and ( ). The same technique fails with < > however, and I
cannot find a workaround,
grid.text(expression(bgroup("<",atop(x,y),">")))
Error in bgroup("<", atop(x, y), ">") : invalid group delimiter
Regards,
baptiste
sessionInfo()
R version
2008 Dec 02
1
legend idea for latticeExtra
Dear list,
I've written a small utility function to add arbitrary legend(s) to a
lattice graph (or a combination of them), much like the legend
function of base graphics. I though perhaps it could be useful to
someone else, or improved by suggestions. I understand this goes
against the lattice paradigm somewhat, in that you short-cut the link
between group variables and the
2010 Sep 21
1
puzzle with integrate over infinite range
Dear list,
I'm calculating the integral of a Gaussian function from 0 to
infinity. I understand from ?integrate that it's usually better to
specify Inf explicitly as a limit rather than an arbitrary large
number, as in this case integrate() performs a trick to do the
integration better.
However, I do not understand the following, if I shift the Gauss
function by some amount the integral
2011 Jul 30
1
grImport symbols
Dear list,
I have two questions regarding grid.symbols() in the grImport package.
This package allows you to import a vector graphic in R, and
grid.symbols() can be used to plot the resulting glyph at arbitrary
locations in a grid viewport.
I have tried the code in the grImport vignette, which is most
interesting, however I am stuck with two problems:
1- Is there a possibility to create a
2009 Mar 25
2
"[.data.frame" and lapply
Dear all,
Trying to extract a few rows for each element of a list of
data.frames, I'm puzzled by the following behaviour,
> d <- lapply(1:4, function(i) data.frame(x=rnorm(5), y=rnorm(5)))
> str(d)
>
> lapply(d, "[", i= c(1)) # fine, this extracts the first columns
> lapply(d, "[", j= c(1, 3)) # doesn't do nothing ?!
>
> library(plyr)
2009 Mar 25
2
"[.data.frame" and lapply
Dear all,
Trying to extract a few rows for each element of a list of
data.frames, I'm puzzled by the following behaviour,
> d <- lapply(1:4, function(i) data.frame(x=rnorm(5), y=rnorm(5)))
> str(d)
>
> lapply(d, "[", i= c(1)) # fine, this extracts the first columns
> lapply(d, "[", j= c(1, 3)) # doesn't do nothing ?!
>
> library(plyr)
2008 Jun 18
2
highest eigenvalues of a matrix
DeaR list,
I happily use eigen() to compute the eigenvalues and eigenvectors of
a fairly large matrix (200x200, say), but it seems over-killed as its
rank is limited to typically 2 or 3. I sort of remember being taught
that numerical techniques can find iteratively decreasing eigenvalues
and corresponding orthogonal eigenvectors, which would provide a nice
alternative (once I have the
2009 Apr 03
3
plyr and table question
Dear all,
I'm puzzled by the following example inspired by a recent question on
R-help,
cc <- textConnection("user_id website time
20 google 0930
21 yahoo 0935
20 facebook 1000
25 facebook 1015
61 google 0940")
d <- read.table(cc, head=T) ; close(cc)
table(d$user_id) # count the
2009 Jun 25
3
grid.polygon() + color gradient
Hi,
I wonder whether there is a way to generate a polygon (a triangle in
my case) with color gradient using grid.polygon() in package grid?
I tried something like
library(grid)
grid.polygon(x=c(0, 0.5, 1), y=c(0.5, 1, 0.5), gp=gpar(col=NA,
fill=colorRampPalette(c("green", "lightgray"),
space="Lab")(200)))
But am only