Question

我有一个[Int]数组，我需要检查所有与另一个元素没有相同值的元素。我想要插入新数组的那些非相同元素。

########################################################################################
## create tables with summary statistic's###############################################
########################################################################################

setwd("C:/Data/nih/data/output/csv/merge")            #choose destination folder

for (result in esc.micro@results){
  print(as.character(result$areaid))                  #print each file name into console as script runs
  census.name <- as.character(result$areaid)          #derive census tract from area ID

  #create table for each census tract using summary statistics
  table.unique <- c(mean(result$selection$BMI, na.rm = TRUE),sum(result$selection$female), sum(result$selection$male), 
                   sum(result$selection$diabet),sum(result$selection$white), sum(result$selection$black),
                   sum(result$selection$indian), sum(result$selection$asian), sum(result$selection$pacific),
                   sum(result$selection$other), sum(result$selection$mixed))
  table.unique <- c(census.name,table.unique)         #combine census tract as column to summary stats
  col.names <- c("areaID","BMI","female","male","diabet","white","black","indian","asian","pacific","other","mixed")
  table.unique <- as.numeric(table.unique)   
  table.unique <-as.data.frame(t(table.unique))       #turn comlums into rows
  names(table.unique) <- col.names                    #add column names
  write.csv(table.unique, file = paste(census.name,".csv", sep=''))         #write csv to output folder
}

#merge all files into single data frame

multmerge = function(mypath){
  filenames=list.files(path=mypath, full.names=TRUE)
  datalist = lapply(filenames, function(x){read.csv(file=x,header=TRUE)})
  Reduce(function(x,y) {merge(x,y)}, datalist)
}

all.tracts <- multmerge("C:/Data/nih/data/output/csv/merge")

希望很清楚，谢谢

Answer 1

这可以在一行中完成：

let numbers = [1, 1, 2, 3, 4, 4] // Here it is values 2,3

let uniques = Set(numbers).filter{ (n) in numbers.filter{$0==n}.count == 1 }

<强>更新

使用Swift 4，您还可以使用字典构造函数来执行此操作：

let uniques = Dictionary(grouping:numbers){$0}.filter{$1.count==1}.map{$0.0}

Answer 2

你可以先检查一下你的数组中是否有多个数字，然后插入一个集合，否则追加该集合不包含它的元素：

let numbers = [1, 1, 2, 3, 4, 4] // Here it is values 2,3
var repeats: Set<Int> = []
var uniques: [Int] = []
for (index, number) in numbers.enumerated() {
    if numbers[(numbers.index(index, offsetBy: 1, limitedBy: numbers.endIndex) ?? numbers.endIndex)..<numbers.endIndex].contains(number) {
        repeats.insert(number)
    } else if !repeats.contains(number) {
        uniques.append(number)
    }
}

uniques   // 2,3

Answer 3

我会使用2套：

var seenOnce: Set<Int> = []
var seenMorethanOnce: Set<Int> = []
let input = [1, 1, 2, 3, 4, 4]

for number in input
{
    if seenMorethanOnce.contains(number)
    {
        // Skip it since it's already been detected as a dupe.
    }
    else if seenOnce.contains(number)
    {
        // We saw it once, and now we have a dupe.
        seenOnce.remove(number)
        seenMorethanOnce.insert(number)
    }
    else
    {
        // First time seeing this number.
        seenOnce.insert(number)
    }
}

当for循环结束时，seenOnce设置将包含您的值，如果您愿意，可以轻松地将其转换为数组。

Swift 3 - 检查，有多少相同元素的数组内容

3 个答案: