如何在.GlobalEnv中的R中提供用户定义函数的输出作为data.frame

时间:2013-03-17 10:55:12

标签: r user-defined-functions rstudio rstudio-server

我创建了一个函数'mywsobj',它接受一个输入& 2输出

用户输入:环境

output1:data.frame名称“wsobj” (对象列表,类,内存使用情况的数据)          输出到控制台 output2:基于对象列表及其内存使用情况的条形图。

到目前为止一切都好,

我的问题1:但如何从用户指定的输入环境中的函数内部或至少在.GlobalEnv中保存“wsobj”data.frame?               我尝试过这样的东西:使用<<,使用pos / parent.environment等。               但事情远远超出了我。

我的问题2:是否可以在R /特别是Rstudio服务器中指定项目特定/用户特定的环境?

虽然我的代码可能无关紧要但仍然如下:

    # creating SOME data
dfAtoZ<- data.frame(LETTERS) 
df1to1Cr <- data.frame(1:10000000)
vec1to1Cr <- as.vector(1:10000000)
mat1to1Cr <- as.matrix(1:10000000)
set.seed<-10
randvec<-runif(1000,min=-100,max=100)
# creating MY function
mywsobj<-function(myenvironmentName)
{#step1 creating vector of object names
wslist <- vector(length=length(ls(myenvironmentName)))
for(i in 1:length(ls(myenvironmentName)))
{wslist[i]<-ls(myenvironmentName)[i]}
# wslist<-cbind(unlist(ls()))
#step2 creating vector of object classes
wsclass <- vector(length=length(wslist))
wsmemKb <- vector(mode="numeric",length=length(wslist))
for(i in 1:length(wslist))
{wsclass[i]<-class(get(wslist[i]))
wsmemKb[i]<- object.size(get(wslist[i]))/1000*1024}
#step4 combining them in a data.frame
wobj<-data.frame(cbind(wslist,wsclass,wsmemKb))
# library(sqldf)
# sqldf("pragma table_info(wobj)") shows col 3(wsmem) still non-numeric
wobj[,3] <- as.numeric( as.character(wobj[,3]) )
# create data to return matrix of memory consumption
objmemsize <- rev(sort(sapply(ls(envir=myenvironmentName), 
                function (object.name)object.size(get(object.name))/1000)))
# draw bar plot
barplot(objmemsize,main="Memory usage by object in myenvironment", 
          ylab="KiloByte", xlab="Variable name", 
            col=heat.colors(length(objmemsize)))
# result <- sqldf("select * from wobj order by 1/wsmemKb")
return(wobj)
#   return(data.frame(myenvironmentName,wobj))
#   return(assign("myname",wobj,envir = .GlobalEnv))
#   attach(wobj,pos=2,"wobj")
return(barplot)
}
# use of mywsobj function
mywsobj(.GlobalEnv)
# saving output of mywsobj function
output<-as.data.frame(mywsobj(.GlobalEnv))   

1 个答案:

答案 0 :(得分:3)

不确定这是否是你所追求的。但是,您可以使用$为该环境分配值。

my_fun <- function(in.env) {
    # you may want to check if input argument is an environment

    # do your computations
    set.seed(45)
    x <- sample(10)
    y <- runif(10)
    in.env$val <- sum(x*y)
}

my_fun(my.env <- new.env())
ls(my.env)
[1] "val"
my.env$val
# [1] 22.30493

或者,您也可以使用assign,如下所示:

my_fun <- function(in.env) {
    # you may want to check if input argument is an environment

    # do your computations
    set.seed(45)
    x <- sample(10)
    y <- runif(10)
    assign("val", sum(x*y), envir=in.env)
}

# assign to global environment
my_fun(globalenv())
> val
# [1] 22.30493

# assign to local environment, say, v
v <- new.env()
my_fun(v)
> v$val
# [1] 22.30493