2016-12-26 25 views
1

我在下面的示例代碼中使用了foreach和doParallel。將全局和函數環境中的對象導出到集羣

library(foreach) 
    library(doParallel) 
    clusters = makeCluster(4) 
    registerDoParallel(clusters) 


    fun1 <- function(param1, param2, param3) 
    { 
    param4 = param1+param2 
    param5 = param2+param3 
    param6 = param3+param1 
    print(ls(envir = environment())) 
    print(ls(envir = .GlobalEnv)) 
    # clusterExport(cl = clusters, varlist = ls(), envir = environment()) 
    clusterExport(cl = clusters, varlist = ls(), envir = .GlobalEnv) 
    mmm = foreach(i = 1:length(param1), .combine = rbind) %dopar% fun2(i, param4, param5, param6) 
    print(mmm) 
    } 

    fun2 <- function(i, param4, param5, param6) 
    { 
    j = param4[i] * param5[i] * param6[i] 
    } 

    param1 = 1:10 
    param2 = 2:11 
    param3 = 3:12 
    fun1(param1, param2, param3) 

在clusterExport的ENVIR說法,當我使用ENVIR = .GlobalEnv,我得到的錯誤

**"Error in get(name, envir = envir) : object 'param4' not found"**

當我使用ENVIR =環境(),錯誤是

**"Error in fun2(i, param4, param5, param6) : task 1 failed - "could not find function "fun2"""**

我的問題是如何能在全球所有對象以及功能環境導出到一個集羣。

回答

0

當你在一個函數中,你不需要手動導出你需要的對象。但是如果您想讓foreachfun1中訪問,您必須通過fun2fun1。 所以,只需要:

fun1 <- function(param1, param2, param3, fun2) 
{ 
    param4 = param1+param2 
    param5 = param2+param3 
    param6 = param3+param1 
    mmm = foreach(i = 1:length(param1), .combine = rbind) %dopar% { 
    fun2(i, param4, param5, param6) 
    } 
    print(mmm) 
} 

fun1(param1, param2, param3, fun2)