用 R 语言将月份映射到季节

Question

我是 R 编程新手。实际上，我想根据月份绘制季节（如冬季、夏季、季风、季风后）。我试过下面的代码。请指导我。

ifelse((air_quality$Month %in% c('12','01','02','04')),air_quality$Seasons = 'Winter',
ifelse((air_quality$Month %in% c('04','05','06')),air_quality$Seasons = 'Summer',
ifelse((air_quality$Month %in% c('07','08','09')),air_quality$Seasons = 'Monsoon','Post Monsoon')))

提前致谢。 美联社

Answer 1

您的示例中的“04”看起来既属于“冬天”又属于“夏天”。 如果我们假设一个月只属于一个季节并且季节是冬季、夏季、季风和后季风，那么您可以将月份转换为季节的方法之一是：

library(stringr) # to produce strings padded with zeros 
air_quality <- data.frame(Month = str_pad(sample(1:12,12, replace=FALSE),
                                          width = 2, 
                                          side = "left", pad="0"))

# Create a mapping vector and print it
( seasons <- c( rep("Winter",2), 
                rep("Summer",3), 
                rep("Monsoon",3), 
                rep("Postmonsoon",3), 
                "Winter") )
#[1] "Winter"      "Winter"      "Summer"      "Summer"      "Summer"      "Monsoon"     "Monsoon"    
#[8] "Monsoon"     "Postmonsoon" "Postmonsoon" "Postmonsoon" "Winter"     

air_quality$Seasons <- seasons[ as.numeric(air_quality$Month) ]
air_quality
#    Month     Seasons
# 1     07     Monsoon
# 2     06     Monsoon
# 3     11 Postmonsoon
# 4     01      Winter
# 5     05      Summer
# 6     09 Postmonsoon
# 7     03      Summer
# 8     08     Monsoon
# 9     10 Postmonsoon
# 10    02      Winter
# 11    04      Summer
# 12    12      Winter