search for: jevalarray

I haven't had time to try using R for over a year, but have a colleage who wants to. We work with time series and our current version of our calendar-time subroutines in java converts both directions between linear time and calendar. We have used calendar time since year 1965 starting out then with Fortran. Calendar time can be CnYrMoDa | CnYrMoDaHr | CnYrMoDaHrMn | CnYrMoDaHrMnSc |

...00] 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 ... > $ V2: chr [1:1000000] "X0" "X1" "X2" "X3" ... > > For comparison using Java directly (includes both generation and reading into R): > >> system.time(temp <- lapply(J("A")$direct(), .jevalArray)) > user system elapsed > 0.962 0.186 0.494 > > So the JSON route is very roughly ~13x slower than using Java directly. Obviously, this will vary by data set type etc. since there is R overhead involved as well: for example, if you have only numeric variables, the JSON route i...

Bare test code: My simple Java test class source and R test code follow: public class RJavTest { public static void main(String[]args) { RJavTest rJavTest=new RJavTest(); } public final static String conStg="testString"; public final static double con0dbl=10000001; public final static double[]con1Arr=new double[] { 10001,10002,10003,10004,10005,10006 }; public final static

...= m + 10] Here the JTest class has a method named myfunc that accepts a double[][] and returns a double[][]. It simply adds 10 to every element. The parameter 'evalArray' is confusing because when evalArray=TRUE the result is NOT evaluated (a list is returned that you then have to apply .jevalArray to do get the answer). There seems to be an option to have a java reference returned instead of the actual matrix. Can the R side manipulate the matrix (on the java side) through this reference? Thanks, Dominick [[alternative HTML version deleted]]

Hi Folks, If you need to send data from Java to R you may consider using the JDataFrame API -- which is used to convert data into JSON which then can be converted into a data frame in R. Here's the project page: https://coherentlogic.com/middleware-development/jdataframe/ and here's a partial example which demonstrates what the API looks like: String result = new JDataFrameBuilder()

Hello, I have a 2D array of type double in java and I want to pass this data to R in order to compute some statistics. Can anyone help me with this ? Jose -- View this message in context: http://r.789695.n4.nabble.com/passing-a-2D-array-from-Java-to-R-tp3387933p3387933.html Sent from the R devel mailing list archive at Nabble.com.

...2 $ V1: num [1:1000000] 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 ... $ V2: chr [1:1000000] "X0" "X1" "X2" "X3" ... For comparison using Java directly (includes both generation and reading into R): > system.time(temp <- lapply(J("A")$direct(), .jevalArray)) user system elapsed 0.962 0.186 0.494 So the JSON route is very roughly ~13x slower than using Java directly. Obviously, this will vary by data set type etc. since there is R overhead involved as well: for example, if you have only numeric variables, the JSON route is 30x slower on r...

...1 1.2 1.4 1.6 1.8 ... >> $ V2: chr [1:1000000] "X0" "X1" "X2" "X3" ... >> >> For comparison using Java directly (includes both generation and reading into R): >> >>> system.time(temp <- lapply(J("A")$direct(), .jevalArray)) >> user system elapsed >> 0.962 0.186 0.494 >> >> So the JSON route is very roughly ~13x slower than using Java directly. Obviously, this will vary by data set type etc. since there is R overhead involved as well: for example, if you have only numeric variables, t...