.local（x，...）中的错误：不是有效的子集

Question

我们在Ubuntu上运行的实验室中有一个24核HP工作站。我们正在使用RStudio并使用并行计算包。以下是我们的代码。

但是，我们总是得到错误消息：.local（x，...）中的错误：不是有效的子集

setwd("/home/physics/Documents/PNU OJT/January")
getwd()
library(RNetCDF)
library(ncdf4)
library(raster)
library(sp)
library(rasterVis)
library(chron)
library(RColorBrewer)
library(lattice)
library(maptools)
library(parallel)
library(rgdal)
library(rgeos)

f <- function(s){ 
    for(i in 1:5){
        mask(s, PHL[PHL@data$OBJECTID== i,])
        MeanPW<- cellStats(mask(s, PHL[PHL@data$OBJECTID== i,]),   
            stat=mean, na.rm=TRUE)
        if (is.na(MeanPW)) (MeanPW<-NaN) 
        MeanPW<-toString(MeanPW)
        date <- substr(list.files(pattern= ".nc")[O], 15, 17)
        date <- as.numeric(date)
        date2 <- as.Date(date, origin = "2002/12/31")
        date1 <- format(date2, "%Y/%b/%d")
        date2 <- as.character(date2)
        year <- substr(date1, 1, 4)
        month <- substr(date1, 6, 8)
        month_name <- substr(date2, 6, 7)
        season <- if (as.numeric(month_name) < 06 | 
            as.numeric(month_name)==12) {"Dry"} else("Wet")
        Table <- cbind(date2, year, month, season, MeanPW, 
           matrix(Classification$Classification)[i], 
           PHL@data$NAME_2[1:length(PHL@data$OBJECTID)], 
           matrix(Region$Region)[1:length(PHL@data$OBJECTID)])
        write.table(Table, paste("Urban", 13, ".csv", sep=""), sep=",", 
           append=TRUE)
    }
    return(Table)
}

cl <- makeCluster(16)

PHL <- readRDS("PHL_adm2.rds")
Classification <- read.csv("Classification.csv")
Region <- read.csv("Region.csv")
PHL@data <- cbind(PHL@data, Classification, Classification$Region)
M <- list.files(pattern= ".nc")
s <- raster(nrow=1800, ncol=3600)

for(O in 1:2){
    Dataname <- M[O]
    AlltheFiles <- open.nc(Dataname)
    read.nc(AlltheFiles)
    PWV <- raster(Dataname)
    PW_PHL <- crop(PWV, PHL)
    s <- resample(PW_PHL, s)
    s <- crop(s, PHL)
    s <- mask(s, PHL)
    clusterApply(cl, s, f)
}

我希望你能帮助我们。