R语言因子化含缩写的调查响应时语法错误的解决方法咨询

问题场景 #

在将赴约时间调查数据转为有序因子时，因因子水平里的I'm lucky to remember the appointment exists!包含单引号，而代码用单引号分隔水平字符串，导致R解析出错，报错信息如下：

Error: unexpected symbol in "factor_appointments <- factor(appointments, order = TRUE, levels =c('10 minutes early','5 minutes early','Precisely on time','A few minutes late','I'm"

下面是三种可行的解决方法：

方法1：用双引号包裹包含单引号的字符串 #

R允许混用单双引号定义字符串，用双引号包裹带单引号的内容，可避免解析冲突：

factor_appointments <- factor(appointments, order = TRUE, 
   levels =c('10 minutes early','5 minutes early',
   'Precisely on time','A few minutes late',
    "I'm lucky to remember the appointment exists!", ''))
factor_appointments
summary(factor_appointments)

方法2：转义字符串里的单引号 #

在单引号前加反斜杠\转义，明确告诉R这是字符串的一部分，而非结束标记：

factor_appointments <- factor(appointments, order = TRUE, 
   levels =c('10 minutes early','5 minutes early',
   'Precisely on time','A few minutes late',
    'I\'m lucky to remember the appointment exists!', ''))
factor_appointments
summary(factor_appointments)

方法3：使用R 4.0+支持的原始字符串 #

用r"(...)"格式包裹字符串，内部的单引号无需转义，写法更直观：

factor_appointments <- factor(appointments, order = TRUE, 
   levels =c('10 minutes early','5 minutes early',
   'Precisely on time','A few minutes late',
    r"(I'm lucky to remember the appointment exists!)", ''))
factor_appointments
summary(factor_appointments)

内容的提问来源于stack exchange，提问作者Cassandra Strand