Question

我有以下数据框

name                surname 
Mr. William John    Mellors
Miss. Wendla Maria  Heininen
Mrs. Sandra         Gonzalez

这取决于＆＃34; name＆＃34;专栏说＆＃34; Mrs＆＃34; ＆＃34;小姐＆＃34; ＆＃34;女士＆＃34;我必须为名为＆＃34; title＆＃34;

的新专栏分配一个或另一个值

例如对于＆＃34; MS＆＃34; ，是已婚男人，因为＆＃34;小姐＆＃34;未婚的女性，或者＃34; Mrs＆＃34;已婚妇女。

这是输出数据集。

 name                surname      title
Mr. William John    Mellors       married men
Miss. Wendla Maria  Heininen      not married women
Mrs. Sandra         Gonzalez      married women

我不知道是否有功能，或使用ifelse并将其分配到我的第一个数据帧。

代码无效，

#dataframe loading
titanic <- read.table("C:/Users/sergio.urrea/Downloads/titanic.csv", header = TRUE, sep = ";")

titanic$title<-ifelse(titanic$name="Master","Hombre soltero",
                    ifelse(titanic$name="Miss","Mujer soltera"))

由于

Answer 1

假设您的data.frame被调用＆＃34; df＆＃34;

df[grepl("^Mr.$",df$name),3] = "married men"
df[grepl("^Miss.$",df$name),3] = "not married women"
df[grepl("^Mrs.$",df$name),3] = "married women"

您还可以明确地参考第3列并保护这些＆＃34;。＆＃34;

df[grepl("^Mr\\.$",df$name),]$title = "married men"
df[grepl("^Miss\\.$",df$name),]$title = "not married women"
df[grepl("^Mrs\\.$",df$name),]$title = "married women"

Answer 2

使用dplyr中的str_detect()和stringr：

library(dplyr)
    library(stringr)

    df = data.frame(name = c("Mr. William John", "Miss. Wendla Maria", "Mrs. Sandra"), 
                        surname  = c(" Mellors", "Heininen", "Gonzalez")) 


        df %>% mutate(title = ifelse(str_detect(name, "Mr."), "married men",
                                     ifelse(str_detect(name, "Mrs."), "married woman",  "not married woman")))

                   name  surname             title
    1   Mr. William John  Mellors       married men
    2 Miss. Wendla Maria Heininen not married woman
    3        Mrs. Sandra Gonzalez       married men

Answer 3

使用ifelse方法：

extern "C" {
    static mut a: [i32; 10];
}

fn set_a(val: i32, index: usize) {
    unsafe {
        a[index] = val;
    }
}

fn get_a(index: usize) -> i32 {
    unsafe { a[index] }
}

基于其他列创建列数据集

3 个答案: