[R] Query about calculating the monthly average of daily data columns

[Rui Barradas]

Hello,

Inline.

Às 17:33 de 12/09/19, Bert Gunter escreveu:
> But she wants *monthly* averages, Rui. 

Thanks, my mistake.

Ergo ave() or tidyData
> equivalent, right?

Maybe. But ave() returns as many values as the input length, this seems 
more suited for tapply or aggregate.


I will first create an example data set.

set.seed(1234)
start <- as.Date("03-01-1994", "%d-%m-%Y")
end <- as.Date("29-12-2000", "%d-%m-%Y")
date <- seq(start, end, by = "day")
date <- date[as.integer(format(date, "%u")) %in% 1:5]
df1 <- data.frame(date,
                   CountryA = rnorm(length(date)),
                   CountryB = rnorm(length(date)))


Now the averages by month

month <- zoo::as.yearmon(df1[[1]])
aggA <- aggregate(CountryA ~ month, df1, mean)
aggB <- aggregate(CountryB ~ month, df1, mean)
MonthReturns <- merge(aggA, aggB)
head(MonthReturns)


Final clean up.

rm(date, month, aggA, aggB)


Hope this helps,

Rui Barradas
> 
> -- Bert
> 
> On Thu, Sep 12, 2019 at 8:41 AM Rui Barradas <ruipbarradas using sapo.pt 
> <mailto:ruipbarradas using sapo.pt>> wrote:
> 
>     Hello,
> 
>     Please include data, say
> 
>     dput(head(data, 20))  # post the output of this
> 
> 
>     But, is the problem as simple as
> 
>     rowMeans(data[2:3], na.rm = TRUE)
> 
>     ?
> 
>     Hope this helps,
> 
>     Rui Barradas
> 
> 
>     Às 15:53 de 12/09/19, Subhamitra Patra escreveu:
>      > Dear R-users,
>      >
>      > I have daily data from 03-01-1994 to 29-12-2000. In my datafile,
>     he first
>      > column is date and the second and third columns are the returns
>     of the
>      > country A, and B. Here, the date column is same for both
>     countries. I want
>      > to calculate the monthly average of both country's returns by
>     using a loop,
>      > and then, I want to export the results into excel.
>      >
>      > Please help me in this regard.
>      >
>      > Please find the attached datasheet.
>      >
>      > Thank you.
>      >
> 
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