> > I am looking for a more elegant way to write below code. > > #Simulation results have different dimensions > mysim <- lapply(1:10, function(y) { > two.mat <- matrix(rnorm(4), nrow = 2) > four.mat <- matrix(rnorm(16), nrow = 4) > list(two.mat = two.mat, four.mat = four.mat) #results with different dimensions > }) > > #Collect different components of simulation results > #Is it possible to do this with implicit loops? > mat2 <- matrix(nrow = 2, ncol = 1) > mat4 <- matrix(nrow = 4, ncol = 1) > for (mat.list in mysim) { > mat2 <- cbind(mat2, mat.list[["two.mat"]]) > mat4 <- cbind(mat4, mat.list[["four.mat"]]) > } > mat2 <- mat2[,-1] > mat4 <- mat4[,-1]
Is this what you want: ## This cbinds all the 2 matrix components of mysim ## producing a 2 x 20 matrix do.call(cbind,lapply(mysim,`[[`,1)) ## Change the 1 to a 2 to cbind the other components. Cheers, Bert Tha On Thu, Jan 26, 2023 at 7:33 PM Naresh Gurbuxani < naresh_gurbuxani at hotmail.com> wrote:> > > > I am looking for a more elegant way to write below code. > > > > #Simulation results have different dimensions > > mysim <- lapply(1:10, function(y) { > > two.mat <- matrix(rnorm(4), nrow = 2) > > four.mat <- matrix(rnorm(16), nrow = 4) > > list(two.mat = two.mat, four.mat = four.mat) #results with different > dimensions > > }) > > > > #Collect different components of simulation results > > #Is it possible to do this with implicit loops? > > mat2 <- matrix(nrow = 2, ncol = 1) > > mat4 <- matrix(nrow = 4, ncol = 1) > > for (mat.list in mysim) { > > mat2 <- cbind(mat2, mat.list[["two.mat"]]) > > mat4 <- cbind(mat4, mat.list[["four.mat"]]) > > } > > mat2 <- mat2[,-1] > > mat4 <- mat4[,-1] > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. >[[alternative HTML version deleted]]
Elegance is in the eyes of the beholder...
extractor <- function( simlist, sim_name ) {
do.call(
cbind
, lapply(
simlist
, function( r ) r[[ sim_name ]]
)
)
}
extractor( mysim, "two.mat" )
... but using do.call will be much more memory efficient than successive cbind
operations.
On January 26, 2023 7:33:25 PM PST, Naresh Gurbuxani <naresh_gurbuxani at
hotmail.com> wrote:>>
>> I am looking for a more elegant way to write below code.
>>
>> #Simulation results have different dimensions
>> mysim <- lapply(1:10, function(y) {
>> two.mat <- matrix(rnorm(4), nrow = 2)
>> four.mat <- matrix(rnorm(16), nrow = 4)
>> list(two.mat = two.mat, four.mat = four.mat) #results with different
dimensions
>> })
>>
>> #Collect different components of simulation results
>> #Is it possible to do this with implicit loops?
>> mat2 <- matrix(nrow = 2, ncol = 1)
>> mat4 <- matrix(nrow = 4, ncol = 1)
>> for (mat.list in mysim) {
>> mat2 <- cbind(mat2, mat.list[["two.mat"]])
>> mat4 <- cbind(mat4, mat.list[["four.mat"]])
>> }
>> mat2 <- mat2[,-1]
>> mat4 <- mat4[,-1]
>
>______________________________________________
>R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.
--
Sent from my phone. Please excuse my brevity.
I would use replicate() to do an operation with random numbers repeatedly:
```
mysim <- replicate(10, {
two.mat <- matrix(rnorm(4), 2, 2)
four.mat <- matrix(rnorm(16), 4, 4)
list(two.mat = two.mat, four.mat = four.mat)
})
```
which should give you a matrix-list. You can slice this matrix-list
just like normal, then cbind it in one step:
```
two.mat <- do.call("cbind", mysim["two.mat", ])
four.mat <- do.call("cbind", mysim["four.mat", ])
```
On Thu, Jan 26, 2023 at 10:33 PM Naresh Gurbuxani
<naresh_gurbuxani at hotmail.com> wrote:>
> >
> > I am looking for a more elegant way to write below code.
> >
> > #Simulation results have different dimensions
> > mysim <- lapply(1:10, function(y) {
> > two.mat <- matrix(rnorm(4), nrow = 2)
> > four.mat <- matrix(rnorm(16), nrow = 4)
> > list(two.mat = two.mat, four.mat = four.mat) #results with
different dimensions
> > })
> >
> > #Collect different components of simulation results
> > #Is it possible to do this with implicit loops?
> > mat2 <- matrix(nrow = 2, ncol = 1)
> > mat4 <- matrix(nrow = 4, ncol = 1)
> > for (mat.list in mysim) {
> > mat2 <- cbind(mat2, mat.list[["two.mat"]])
> > mat4 <- cbind(mat4, mat.list[["four.mat"]])
> > }
> > mat2 <- mat2[,-1]
> > mat4 <- mat4[,-1]
>
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.