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Subset a dataframe between 2 dates

Tags:

date

r

subset

I am working with daily returns from a Brazilian Index (IBOV) since 1993, I am trying to figure out the best way to subset for periods between 2 dates.

The data frame (IBOV_RET) is as follows :

head(IBOV_RET)         DATE    1D_RETURN 1 1993-04-28 -0.008163265 2 1993-04-29 -0.024691358 3 1993-04-30  0.016877637 4 1993-05-03  0.000000000 5 1993-05-04  0.033195021 6 1993-05-05 -0.012048193 ... 

I set 2 variables DATE1 and DATE2 as dates

DATE1 <- as.Date("2014-04-01") DATE2 <- as.Date("2014-05-05") 

I was able to create a new subset using this code:

TEST <- IBOV_RET[IBOV_RET$DATE >= DATE1 & IBOV_RET$DATE <= DATE2,] 

It worked, but I was wondering if there is a better way to subset the data between 2 date, maybe using subset.

like image 515
RiskTech Avatar asked May 13 '14 03:05

RiskTech


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1 Answers

As already pointed out by @MrFlick, you dont get around the basic logic of subsetting. One way to make it easier for you to subset your specific data.frame would be to define a function that takes two inputs like DATE1 and DATE2 in your example and then returns the subset of IBOV_RET according to those subset parameters.

myfunc <- function(x,y){IBOV_RET[IBOV_RET$DATE >= x & IBOV_RET$DATE <= y,]}  DATE1 <- as.Date("1993-04-29") DATE2 <- as.Date("1993-05-04")  Test <- myfunc(DATE1,DATE2)      #> Test #        DATE  X1D_RETURN #2 1993-04-29 -0.02469136 #3 1993-04-30  0.01687764 #4 1993-05-03  0.00000000 #5 1993-05-04  0.03319502 

You can also enter the specific dates directly into myfunc:

myfunc(as.Date("1993-04-29"),as.Date("1993-05-04")) #will produce the same result 
like image 117
talat Avatar answered Sep 21 '22 18:09

talat