Para substituir todos os valores de ND por zero ou outro conteúdo é necessário transformar dados a partir de um conjunto de dados de entrada para um conjunto de dados de saída utilizando a funçãorxDataStep.Um script de exemplo para substituir todos os ND no ficheiro xdf "AirlineDemoSmall.xdf" é apresentado abaixo:
# Create a data frame with missing valuesset.seed(17)myDataF <- data.frame(x = rnorm(100), y = runif(100), z = rgamma(100, shape = 2))xmiss <- seq.int(from = 5, to = 100, by = 5)ymiss <- seq.int(from = 2, to = 100, by = 5)myDataF$x[xmiss] <- NAmyDataF$y[ymiss] <- NA# Convert into a xdfmyDataNA<-file.path(getwd(),"myDataNA.xdf")trsfxdf<-rxDataStep(inData=myDataF,outFile=myDataNA,overwrite=TRUE)writeLines("\n\nXdf Generated with random NA values")print(rxGetInfo(myDataF, n = 15)$data) # Test ouput data #### Use from here if there is an existing xdf.## replace myDataNA with your xdf file##writeLines("\n\nVariables that contains NA values (Missing Observations)")(mySum <- rxSummary(~., data = myDataNA)$sDataFrame)# Find variables that are missingtransVars <- mySum$Name[mySum$MissingObs > 0]print(transVars) #Test detected variables# create a function to replace NA vals with meanNAreplace <- function(dataList) { replaceFun <- function(x) { x[is.na(x)] <- replaceValue return(x) } dataList <- lapply(dataList, replaceFun) return(dataList)}#myDataRMV<-file.path(getwd(),"myDataRMV.xdf") # Replace Missing Value trsfxdf<- rxDataStep(inData = myData1, outFile = myDataRMV, transformFunc = NAreplace, transformVars = transVars, transformObjects = list(replaceValue = "REPLACED MISSING VALUE"), overwrite=TRUE)writeLines("\n\nTransformed xdf with NA replaced by Value")print(rxGetInfo(myDataRMV, n=15)$data) # Test output data
