How to generate fixed values for month and day in R lan…

In R language, you can generate dates with fixed month and day values using the date function as.Date() and time function as.POSIXct().

Here are some sample codes for generating a date with the month and day as April 15th.

# 生成当前年份的4月15日的日期
current_year <- as.numeric(format(Sys.Date(), "%Y")) # 获取当前年份
fixed_date <- as.Date(paste(current_year, "04-15", sep = "-")) # 生成日期
print(fixed_date)

# 生成特定年份的4月15日的日期
specific_year <- 2022 # 指定年份
fixed_date <- as.Date(paste(specific_year, "04-15", sep = "-")) # 生成日期
print(fixed_date)

The result displayed is:

[1] "2022-04-15"

In the above code, the current year is obtained using as.numeric(format(Sys.Date(), “%Y”)), and then combined with a fixed month and day using the paste() function to create a string. Next, the string is converted to a date format using as.Date().

If you need to create dates with times, you can use the as.POSIXct() function. Here is an example code for generating a date and time for 10 AM on April 15th.

# 生成当前年份的4月15日上午10点的日期和时间
current_year <- as.numeric(format(Sys.Date(), "%Y")) # 获取当前年份
fixed_datetime <- as.POSIXct(paste(current_year, "04-15 10:00:00", sep = "-")) # 生成日期和时间
print(fixed_datetime)

# 生成特定年份的4月15日上午10点的日期和时间
specific_year <- 2022 # 指定年份
fixed_datetime <- as.POSIXct(paste(specific_year, "04-15 10:00:00", sep = "-")) # 生成日期和时间
print(fixed_datetime)

The output/result is:

[1] "2022-04-15 10:00:00 CST"

In the above code, the paste() function is used to combine the year, month/day, and hour/minute/second into a string, and then the as.POSIXct() function is used to convert the string into a date and time format.