Displaying 20 results from an estimated 7000 matches similar to: ""[<-" plus drop-type extra argument"
2006 Oct 31
1
setReplaceMethod
Hi
If x <- 1:10 then x[5] <- 1i will promote
x to be a complex vector.
Suppose I have an S4 class "brob", and have functions
is.brob(), as.brob(), as.numeric() and so forth (minimal self-contained
code below).
If x is numeric (1:10, say) and y is a brob, what
is the best way to make
x[5] <- y
promote x to a brob in the same way as the complex example?
Or is
2008 May 07
1
optional setValidity()
Hi
Suppose I have an S4 class "foo" and a validity checking
function ".checkfoo()":
setClass("foo", representation=representation("numeric"))
setValidity("foo" , .checkfoo)
is fine; in my application, .checkfoo() verifies that a bunch
of necessary conditions are met.
But .checkfoo() is very time consuming and I want
to give users the option
2005 Jun 13
3
extracting components of a list
Hi
how do I extract those components of a list that satisfy a certain
requirement? If
jj <- list(list(a=1,b=4:7),list(a=5,b=3:6),list(a=10,b=4:5))
I want just the components of jj that have b[1] ==4 which in this case
would be the first and
third of jj, viz list (jj[[1]],jj[[3]]).
How to do this efficiently?
My only idea was to loop through jj, and set unwanted components to
NULL,
2004 Sep 08
3
do.call("[", ...) question
Hi again everyone
I have an arbitrarily dimensional array "a" and a list "jj" of length
length(dim(a)). The elements of jj are vectors of indexes.
How do I use do.call() to extract a[ jj[[1]], jj[[2]], jj[[3]], ...] ?
Toy example follows:
a <- matrix(1:30,5,6)
jj <- list(5:1,6:1)
I want the following
a[ jj[[1]],jj[[2]] ]
How do I do this?
OBAttempts:
2007 Apr 17
1
no visible binding for global variable
Hello everyone
I am trying to get one of my packages through R's QC.
The package is clean for me under R-2.4.1, R-2.5.0, and
R-devel, but Kurt gets
>
> * checking R code for possible problems ... WARNING
> hypercube: no visible binding for global variable ?f?
Function hypercube() [cut-&-pasted below] is intended to
return an adjacency matrix for an n-dimensional
2020 Feb 11
3
[v 2.3.4.1][quota] recalculation
Hello,
I can't find the information on the wiki :(
When is the quota recalculated after a mail deletion ?
For instance, I am running low of storage and I use Thunderbird to
delete large mail. I only notice a recalculation when I quit
Thunderbirdb and I relaunch it.
Even, with doveadm CLI, as long as Thunderbird is not disconnected on
the client side, the server didn't recalculate the
2004 Jan 14
1
arrows on contour lines
Hello everybody
I'm using contour() to draw streamlines of potential flow, eg
jj <- seq(from= -4, to=4,len=20)
jj <- outer(jj,jj,function(x,y){x})+1i*outer(jj,jj,function(x,y){y})
f <- function(x){x^2}
contour(Im(f(jj)), nlevels=44 , labels="")
How best to put arrows on the contour lines to show the direction of flow?
(ie I want contour lines looking like
2005 Dec 05
1
apply() and dropped dimensions
Hi
I am having difficulty with apply(). I want apply() to return a
matrix, but sometimes a vector is returned.
Toy example follows.
Function jj() takes a couple of matrices m1 and m2 as arguments
and returns a matrix with r rows and c columns where r=nrow(m2)
and c=nrow(m1).
jj <- function(m1,m2,f,...){
apply(m1, 1, function(y) {
apply(m2, 1, function(x) {
f(x, y, ...)
2008 Mar 26
5
S4 slot with NA default
Hi
How do I specify an S4 class with a slot that is potentially numeric,
but NA
by default? I want the slot to be NA until I calculate its value
(an expensive operation, not needed for all applications). When
its value is
known, I will create a new object with the correct value inserted in
the slot.
I want "NA" to signify "not known".
My attempt fails because
2015 Aug 21
3
Would a spreadsheet be a good project using LLVM?
I am thinking about writing a new open source spreadsheet
application since I think the spreadsheet applications out
there (Microsoft Excel, LibreOffice Calc, etc.) do not have
some features that I would really like to use. I would like
the spreadsheet to recalculate very fast and wondered if it
would make sense to use LLVM to calculate the cell values
quickly. Each cell of a spreadsheet
2007 Jun 27
1
inherits() and virtual classes
Hi
How do I test for an object having a particular virtual class?
In the following, "onion" is a virtual class, and "octonion" is
a non-virtual class contained in onion. The last call
to inherits() gives FALSE [R-2.5.0], when inherits.Rd led
me to expect TRUE.
setClass("onion",
representation = "VIRTUAL"
)
2015 Aug 21
3
Would a spreadsheet be a good project using LLVM?
Mats,
Thanks for your feedback. I guess I should elaborate on one
of the features I would like to implement. In today's
spreadsheets if you want to crunch a lot of data, you
usually put the data in rows and put expressions in cells to
the right of the data and repeat those cells for every row
of the data. I would like to create a spreadsheet system
that can process the same quantity of
2007 Dec 19
3
array addition
Hi
suppose I have two arrays x1,x2 of dimensions a1,b1,c1 and
a2,b2,c2 respectively.
I want x = x1 "+" x2 with dimensions c(max(a1,a2), max(b1,b2),max
(c1,c2))
with
x[a,b,c] = x1[a1,b1,c1] + x2[a2,b2,c2] if a <=min(a1,a2) , b<=min
(b1,b2), c<=min(c1,c2)
and the other bits either x1 or x2 or zero according to whether the
coordinates
are "in range" for
2005 Oct 05
2
eliminate t() and %*% using crossprod() and solve(A,b)
Hi
I have a square matrix Ainv of size N-by-N where N ~ 1000
I have a rectangular matrix H of size N by n where n ~ 4.
I have a vector d of length N.
I need X = solve(t(H) %*% Ainv %*% H) %*% t(H) %*% Ainv %*% d
and
H %*% X.
It is possible to rewrite X in the recommended crossprod way:
X <- solve(quad.form(Ainv, H), crossprod(crossprod(Ainv, H), d))
where quad.form() is a little
2004 Oct 26
1
persp(), scatterplot3d(), "..." argument
Hello list.
I very often need 3d scatterplots, and use scatterplot3D quite a lot.
I am trying to modify persp() to plot scatterplots, and make use of
the theta and phi arguments that persp() offers. I am having some
difficulty passing the correct arguments to persp().
Here is my function so far. Much of it is copied from the persp() manpage.
points3d <- function(x,y,z,
2004 Oct 26
1
persp(), scatterplot3d(), "..." argument
Hello list.
I very often need 3d scatterplots, and use scatterplot3D quite a lot.
I am trying to modify persp() to plot scatterplots, and make use of
the theta and phi arguments that persp() offers. I am having some
difficulty passing the correct arguments to persp().
Here is my function so far. Much of it is copied from the persp() manpage.
points3d <- function(x,y,z,
2004 Oct 01
2
multiple dimensional diag()
Hi
I have two arbitrarily dimensioned arrays, "a" and "b", with
length(dim(a))==length(dim(b)). I want to form a sort of
"corner-to-corner" version of abind(), or a multidimensional version
of blockdiag().
In the case of matrices, the function is easy to write and if
a=matrix(1,3,4) and b=matrix(2,2,2), then adiag(a,b) would return:
[,1] [,2] [,3] [,4] [,5]
2009 Jan 13
2
particulars of importing/loading libraries
Dear List:
Sorry for posting maybe a trivial question, but I have a basic
understanding problem. If I have say pack1 and pack2, two R packages,
and pack2 depends on and imports pack1 fully (as in the code below), is
there a way to make all the functionality of pack1 available for the
global and other environments (not only for the functions called from
withing pack2) by loading pack2 only? I
2008 Apr 07
3
Overriding axis formatting with custom Axis method, Axis.numeric etc
Dear list:
I would like to override the default way R formats plot axes with a
custom method(s). Obviously I would prefer to define it as general as
possible avoiding writing a custom method for each individual class
where possible.
The plot.default method (and I assume other methods as well) calls
Axis(...) to produce the axis layout depending on data. In this sense it
seems reasonable to
2005 Feb 07
4
proportional matrix rows
Hi
I have a two-column integer matrix like this:
R> jj
[,1] [,2]
[1,] -1 1
[2,] -2 2
[3,] -7 6
[4,] -8 7
[5,] -6 5
[6,] -9 8
[7,] -5 4
[8,] 3 -3
[9,] -10 9
[10,] -4 3
I want a diagnostic that detects whether a row is a multiple of
the first row or not. In this case, this would be rows 1,2, and 8.
How to do this