如何使用 R 将年度数据转换为月度数据？

Question

我有 2000-2015 年 15 年的 GDP 年度数据。我想将此数据转换为只有月份和年份的月度数据。

我只想将那一年的值复制到所有月份。我怎么能在 R.e.g 中做到这一点2010 年的值为 1708。我想为 2010 年的所有月份复制相同的值。

我的数据：

> str(gdpnew)
'data.frame':   16 obs. of  3 variables:
 $ X    : int  1 2 3 4 5 6 7 8 9 10 ...
 $ Date : Date, format: "2000-12-31" "2001-12-31" "2002-12-31" ...
 $ Value: num  477 494 524 618 722 ...

> head(gdpnew)
  X       Date   Value
1 1 2000-12-31 476.636
2 2 2001-12-31 493.934
3 3 2002-12-31 523.768
4 4 2003-12-31 618.369
5 5 2004-12-31 721.589
6 6 2005-12-31 834.218
>

Answer 1

显然你想要交叉连接：

DT <- read.table(text = "  X       Date   Value
1 1 2000-12-31 476.636
2 2 2001-12-31 493.934
3 3 2002-12-31 523.768
4 4 2003-12-31 618.369
5 5 2004-12-31 721.589
6 6 2005-12-31 834.218", header = TRUE)

library(data.table)
setDT(DT)

DT[, Date := as.IDate(Date)]
DT[, year := year(Date)]
setkey(DT, year)
DT1 <- DT[CJ(year, month = 1:12)]
print(DT1)

#    X       Date   Value year month
# 1: 1 2000-12-31 476.636 2000     1
# 2: 1 2000-12-31 476.636 2000     2
# 3: 1 2000-12-31 476.636 2000     3
# 4: 1 2000-12-31 476.636 2000     4
# 5: 1 2000-12-31 476.636 2000     5
# 6: 1 2000-12-31 476.636 2000     6
# 7: 1 2000-12-31 476.636 2000     7
# 8: 1 2000-12-31 476.636 2000     8
# 9: 1 2000-12-31 476.636 2000     9
#10: 1 2000-12-31 476.636 2000    10
#11: 1 2000-12-31 476.636 2000    11
#12: 1 2000-12-31 476.636 2000    12
#13: 2 2001-12-31 493.934 2001     1
#14: 2 2001-12-31 493.934 2001     2
#15: 2 2001-12-31 493.934 2001     3
#16: 2 2001-12-31 493.934 2001     4
#17: 2 2001-12-31 493.934 2001     5
#18: 2 2001-12-31 493.934 2001     6
#19: 2 2001-12-31 493.934 2001     7
#20: 2 2001-12-31 493.934 2001     8
#21: 2 2001-12-31 493.934 2001     9
#22: 2 2001-12-31 493.934 2001    10
#23: 2 2001-12-31 493.934 2001    11
#24: 2 2001-12-31 493.934 2001    12
#25: 3 2002-12-31 523.768 2002     1
#26: 3 2002-12-31 523.768 2002     2
#27: 3 2002-12-31 523.768 2002     3
#28: 3 2002-12-31 523.768 2002     4
#29: 3 2002-12-31 523.768 2002     5
#30: 3 2002-12-31 523.768 2002     6
#31: 3 2002-12-31 523.768 2002     7
#32: 3 2002-12-31 523.768 2002     8
#33: 3 2002-12-31 523.768 2002     9
#34: 3 2002-12-31 523.768 2002    10
#35: 3 2002-12-31 523.768 2002    11
#36: 3 2002-12-31 523.768 2002    12
#37: 4 2003-12-31 618.369 2003     1
#38: 4 2003-12-31 618.369 2003     2
#39: 4 2003-12-31 618.369 2003     3
#40: 4 2003-12-31 618.369 2003     4
#41: 4 2003-12-31 618.369 2003     5
#42: 4 2003-12-31 618.369 2003     6
#43: 4 2003-12-31 618.369 2003     7
#44: 4 2003-12-31 618.369 2003     8
#45: 4 2003-12-31 618.369 2003     9
#46: 4 2003-12-31 618.369 2003    10
#47: 4 2003-12-31 618.369 2003    11
#48: 4 2003-12-31 618.369 2003    12
#49: 5 2004-12-31 721.589 2004     1
#50: 5 2004-12-31 721.589 2004     2
#51: 5 2004-12-31 721.589 2004     3
#52: 5 2004-12-31 721.589 2004     4
#53: 5 2004-12-31 721.589 2004     5
#54: 5 2004-12-31 721.589 2004     6
#55: 5 2004-12-31 721.589 2004     7
#56: 5 2004-12-31 721.589 2004     8
#57: 5 2004-12-31 721.589 2004     9
#58: 5 2004-12-31 721.589 2004    10
#59: 5 2004-12-31 721.589 2004    11
#60: 5 2004-12-31 721.589 2004    12
#61: 6 2005-12-31 834.218 2005     1
#62: 6 2005-12-31 834.218 2005     2
#63: 6 2005-12-31 834.218 2005     3
#64: 6 2005-12-31 834.218 2005     4
#65: 6 2005-12-31 834.218 2005     5
#66: 6 2005-12-31 834.218 2005     6
#67: 6 2005-12-31 834.218 2005     7
#68: 6 2005-12-31 834.218 2005     8
#69: 6 2005-12-31 834.218 2005     9
#70: 6 2005-12-31 834.218 2005    10
#71: 6 2005-12-31 834.218 2005    11
#72: 6 2005-12-31 834.218 2005    12
#    X       Date   Value year month

您可能需要设置 allow.cartesian = TRUE。

如何使用 R 将年度数据转换为月度数据？

How to convert annual data to monthly data using R?

r

economics

bigdata