I use iruby on jupyter. In ipython, one can obtain last evaluated value by local variable _. Is it possible to do somehow achieve it in iruby?
I think you have just found another IRuby bug.
Thank you for finding this.
https://github.com/SciRuby/iruby/issues/245
Related
I am trying use simple slice operator as follows, but the result is not correct.
arr = c(1,2,3,4,5,6,7)
arr[2:2+3]
I expected to get the sliced array 2,3,4,5 but instead I get 5. Does R interpret arr[2:2+3] as arr[2:2]+3 ? If so, then why?
The correct version of slice would be arr[2:(2+3)], right?
As #camille pointed out in the comment section, the reason of failure is due to the order of operations!
I am trying to use update function on survey.design object. For instance, I want to create a variable that is the mean of 4 other variables, as follows
x1<-runif(3)
x2<-runif(3)
x3<-runif(3)
population=10000
testdf<-data.frame(x1,x2,x3,population)
testsvy<-svydesign(id=~1,weights=c(30,30,30),data=testdf)
testsvy<-update(testsvy,avg=mean(c(x1,x2,x3)))
However this returns a vector of the same number for every person. There must be something wrong. Alternatively I can modify on test$variables, but I don't feel that this is the easiest way...
OK I got the answer myself... Hope that it could be simpler since I type the object names three times...
testsvy<-update(testsvy,avg2=rowMeans(testsvy$variables[,c("x1","x2","x3")],na.rm=TRUE))
So I imported the file and saved it as Purity and its clearly imported. I tried t-test but it doesn't recognize my variables. I tried using the names function to retrieve the variable names and its exactly what I'm entering, V1 and V2. I also tried with Lab-1 and Lab-2. I also tried just using dataset=Purity, all to no avail.
I took a screenshot so as to show code and that data is in the studio, can anyone tell me why this is not working?
apologies if this is painfully obvious I was only introduced to R for stats last week and am still a beginner, also don't have much experience with programming in general. I have looked at other similar problems but just cant see why mine aren't being recognised and others are.
You've got 2 issues here:
1). You don't show how you imported the dataset but you need to either remove the first row or (better) name the columns correctly. I'm assuming you imported the data with read.table(). If so, then include the argument header = TRUE when you import the data.
2). You need to tell R where you want it to get Lab-1 and Lab-2 from.
with(Purity, t.test(Lab-1, Lab-2, paired = TRUE))
r is case sensitive. It looks like your script is using a lowercase 'v" when its an upper case "V" in your variable names.
The problem is in the way you have named your variable. r doesn't recognise the hyphen (-) as a legitimate part of a variable name. Try using underscore (_) instead.
I am writing a vector to a file in R. However the output comes on 2 lines. I wanted all the values to come on a single line. Can you let me know how to fix this
write(value,file=fileconn,append=TRUE,sep="\t")
The o/p comes as follows
1777.167 1825.167 1873.167 1921.167 1969.167
2017.167
Regards
Ganesh
I'm not sure write() is probably not the best choice, but if you want to use it, it might be a good idea to check the ?write help file. It does have an ncolumns= parameter which defaults to 5 for simple numeric vectors.
I would think cat() would be a better solution for just dumping numeric vectors.
This sounds like a silly question, but I really can't find an answer around.
I'm using Scilab to evaluate two methods in terms of performace. However, every time I tell Scilab to calculate anything, it will print the results. Since I'm using large matrices, it spends much more time printing the results than doing the calculations, so I'm having a hard time telling how long is each method actually taking.
Can I get Scilab to compute something without printing the result?
That is, instead of
-->B = A'*A
A =
1. 2. 3.
2. 4. 6.
3. 6. 9.
-->
I'd like it to do
-->B = A'*A
-->
Also simply adding a semicolon works
-->B = A'*A;
-->
Well, I finally found the right query. When I searched for 'scilab silent', one of the results (not the first) was this:
http://help.scilab.org/docs/5.3.3/en_US/mode.html
Function mode(k) lets you choose how Scilab will behave in terms of variable display. The following call will temporarily hide results:
mode(-1)
Whereas this will get you back to the default option:
mode(2)
The documentation is confusing, though.
Please notices that mode does not used at prompt, only in an exec-file or a scilab function.
Aside from the awful English, this notice seems to be outdated. This function worked perfectly for me on the prompt.