大家好，我想要在R里用Maxent模型，但总是提示文件不存在
以下是我的代码

maxent <- ("maxent.jar")

outdir <- ("OutputDirectory")

gridfolder <- ("D:/TIFF/asc")

occurrencelocations<-("VariablesAtArtemisiaannua.csv")

backgroundlocations<-("VariablesAtArtemisiaannuaBg.csv")

additionalargs="autorun=true,plots=true,writeplotdata=true,visible=false,randomseed=true,writebackgroundpredictions=false,replicates=10,replicatetype=subsample,randomtestpoints=50,redoifexists,writemess=false,writeclampgrid=true,askoverwrite=false,pictures=true,outputgrids=true,outputformat=raw"

contributionthreshold <- 5

correlationthreshold <- 0.9

betamultiplier=seq(2,6,0.5)

library("MaxentVariableSelection")

VariableSelection(maxent,outdir,gridfolder,occurrencelocations,backgroundlocations,additionalargs,contributionthreshold,correlationthreshold,betamultiplier)

R提示错误

Error in .rasterObjectFromFile(x, band = band, objecttype = "RasterLayer",  :

  Cannot create a RasterLayer object from this file. (file does not exist)

我想请问是哪个文件出了问题，该怎么解决呢
谢谢大家