Displaying 20 results from an estimated 1200 matches similar to: "Wildcard for indexing?"
2015 Aug 31
2
alloca combining, not (yet) possible ?
Hello
since my broad RFC request didn't catch any responses, let me get a bit
more into the nitty-gritty:
I tried to get llvm (3.7) to optimize superflous allocas away, but so
far I haven't figured out how. Is there no optimizer for this ? Should I
adorn something with some attributes ? As far as I can tell no, but I am
no llvm expert...
For what I want to do, i will probably have a
2015 Aug 31
2
alloca combining, not (yet) possible ?
Caldarale, Charles R schrieb:
> You have not provided us with the declaration for f(). Unless its argument is marked with the nocapture attribute, the compilation of g() cannot assume that f() has not retained a pointer to the x struct and is using it in the second call.
>
thanks a lot for the input. Yes, I forgot to that. The C function
declaration would have been
void f( struct a_b
2015 Aug 28
2
RFC: alloca -- specify rounding factor for allocation (and more)
Hi
sorta piggybacking on the other thread. I am looking for some feedback
on how to implement the following idea in llvm.
The really short version of the idea is this:
* I want to alloca a field (record/struct), so that its size is an even
multiple of 64 bytes. [^1]
* This allocaed field will be exclusively used as an argument to functions
* llvm should be aware of the extra bytes and should
2017 Aug 04
2
Why is as.function() slower than eval(call("function"())?
(Apologies if this is better suited for R-help.)
On my system (macOS Sierra, late 2014 MacBook Pro; R 3.4.1, Homebrew build), I found that it is faster to construct a function using eval(call("function", ...)) than using as.function(list(...)). Example:
make_fn_1 <- function(a, b) eval(call("function", a, b), env = parent.frame())
make_fn_2 <- function(a, b)
2012 Oct 14
4
listing the files in a directory using regular expressions
Hi Experts,
This might be silly question that I am asking, but no way as I am new to
R.
I want to list the files in a directory using regular expression like
A_B*_C*.csv etc.
How to make this possible in R ?
I tried like this list.files(dir=".", pattern="A_B*_C*.csv") but this gives
no output, whereas list.files(.... pattern="*.csv") giving all the .csv
files in
2011 Dec 06
5
Argument validation within functions
Hi,
I just started with writing functions in R and so some questions popped up.
I provide some values as argument to my function such as:
function(a,b,c){}
Now i want that the function first checks if the arguments are valid for the function. E.g argument "a" has to be a number in the range 0-1. How can that easily done?
So far I have:
a <- as.numeric(a)
if(0 <= a &&
2012 Feb 03
2
Assigning objects to variable and variable to list in a for loop
Hello,
I want to use a for loop for repeadely calculating
a maxent model (package dismo, function maxent()) which
creates an object of the class maxent (S4).
I want to collect all the resulting object in a list.
I tried to simplify my for loop to explain what I want.
There are two problems/questions:
1) How can I create the new variables in the loop (using paste) and assign the objects
2) How
2011 Aug 15
2
Extracting information from lm results (multiple model runs)
Just to inform:
I posted that before in R-sig-ecology but as it might be interesting also for other useRs, I post it also to the general r-user list:
Hello Alexandre,
thank you very much. I also found another way to extract summarizing information from lm results over e.g. 1000 repeated model runs:
results2 <- t(as.data.frame(results))
summary(results2)
Although some questions popped up in
2012 May 31
3
Remove columns from dataframe based on their statistics
Hi,
I have a dataframe and want to remove columns from it
that are populated with a similar value (for the total
column) (the variation of that column is 0). Is there an
easier way than to calculate the statistics and then
remove them by hand?
A <- runif(100)
B <- rep(1,100)
C <- rep(2.42,100)
D <- runif(100)
df <- data.frame(A,B,C,D) # if want to conditionally remove column B and
2011 May 19
1
Feature request: extend functionality of 'unlist()' by args 'delim=c("/", "_", etc.)' and 'keep.special=TRUE/FALSE'
Dear list,
I hope this is the right place to post a feature request. If there's
exists a more formal channel (e.g. as for bug reports), I'd appreciate a
pointer.
I work a lot with named nested lists with arbitrary degrees of
"nestedness". In order to retrieve the names and/or values of "bottom
layer/bottom tier", I love the functionality of 'unlist()', or
2006 May 17
2
Association data clobbering (foreign keys too?)
Can someone please confirm or correct the following statements?
If I have the following tables
create table as (id int, [...], b_id int);
create table bs (id int, [...], a_id int);
create table as_bs (a_id int, b_id int);
and the associations woould be defined like this
class A << ...
habtm :bs
belongs_to :b
end
so my Model A has a habtm collection of Bs *plus* a direct
2012 Jun 08
4
Sort 1-column dataframe with rownames
Hi,
I have a 1-column dataframe with rownames and I want to sort it
based on the single column. The typical procedure that is recommended
in diverse posts is to use order in the index. But that "destroys" my
dataframe structure. Probabaly it is a very simple solution. Here is a
short reproducable example:
x <- c(1,3,51,2,34,44,12,33,2,8)
df <- data.frame(x)
rownames(df) <-
2013 Mar 02
3
if value is in vector, perform this function
Hi,
I'm trying to set up R to run a simulation of two populations in which every 3.5 days, the initial value of one of the populations is reset to 1.5. I'm simulation an experiment we did in which we fed Daphnia populations twice a week with algae, so I want the initial value of the algal population to reset to 1.5 twice a week to simulate that feeding. I've use for loops and if/else
2011 Aug 15
2
MCMC regress, using runif()
Hello,
just to follow up a question from last week. Here what I've done so far (here an example):
library(MCMCpack)
Y=c(15,14,23,18,19,9,19,13)
X1=c(0.2,0.6,0.45,0.27,0.6,0.14,0.1,0.52)
X2a=c(17,22,21,18,19,25,8,19)
X2b=c(22,22,29,34,19,26,17,22)
X2 <- function()runif(length(X2a), X2a, X2b)
model1 <- MCMCregress(Y~X1+X2())
summary(model1)
but I am not sure if my X2-function is
2017 Apr 09
2
[Bug] FTS invalid address parsing
Hi,
i found another bug in FTS while parsing
quoted-printable/base64-encoded sender's name inside 'From' header
(again, i was figuring out why some of messages cannot be searched).
Header: From: =?UTF-8?Q?A=2CB?= <test at example.com>
Data send to Solr by Dovecot: <field name="from">A@, B
&lt;test at example.com&gt;</field>
Header:
2010 Oct 26
4
divide column in a dataframe based on a character
Hello,
If I have a dataframe:
example(data.frame)
zz<-c("aa_bb","bb_cc","cc_dd","dd_ee","ee_ff","ff_gg","gg_hh","ii_jj","jj_kk","kk_ll")
ddd <- cbind(dd, group = zz)
and I want to divide the column named group by the "_", how would I do this?
so instead of the first row being
x
2007 Sep 09
2
Batch mode scenario ("use case")
Hello,
I came up with this scenario of the use of batch mode while
thinking of back-up schemes to use for myself. However, it could
be that the last step needed in this scenario is not supported by
rsync! Here's the scenario:
At one time, /c/home/wer/work and /e/gold had identical content
and were really huge (say, 200 GBytes).
After some complex, intricate work, Mr. Wer
2011 Nov 24
2
dataframe indexing by number of cases per group
Hello,
assume we have following dataframe:
group <-c(rep("A",5),rep("B",6),rep("C",4))
x <- c(runif(5,1,5),runif(6,1,10),runif(4,2,15))
df <- data.frame(group,x)
Now I want to select all cases (rows) for those groups
which have more or equal 5 cases (so I want to select
all cases of group A and B).
How can I use the indexing for such questions?
df[??]...
2012 May 11
2
text(): combine expression and line break
Hi,
I would like to plot some extra text in my plot.
This should be a two line text including a special character (sigma).
I tried so far a to use expression in combination with paste and "\n"...
but I can't get the line break...
Here what I've done so far:
plot(1,type="n", xaxt='n', yaxt='n', ann=FALSE)
text(1,1,labels=expression(paste(sigma,"\n
2011 Nov 03
2
variable transformation for lm
Hello,
I am doing a simple regression using lm(Y~X).
As my response and my predictor seemed to be skewed
and I can't meet the model assumptions. Therefore
I need to transform my variables.
I wanted to ask what is the preferred way to find out
if predictor and/or response needs to be transformed
and if yes how (log-transform?).
I found a procedure in "A modern approach to Regressoin
in