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Data Analytics Corp.-2

Date formats

Hi,

I imported an excel table (using read.csv) of Dow Jones monthly average
closings where the first variable is a date as a character string such
as "01OCT1928". How do I convert this to a date variable so I can plot
monthly average closings against date using ggplot2?

Thanks,

Walt

________________________

Walter R. Paczkowski, Ph.D.
Data Analytics Corp.
44 Hamilton Lane
Plainsboro, NJ 08536
________________________
(V) 609-936-8999
(F) 609-936-3733
[hidden email]
www.dataanalyticscorp.com

______________________________________________
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and provide commented, minimal, self-contained, reproducible code.

David Winsemius

Re: Date formats

On Jun 19, 2012, at 8:00 AM, Data Analytics Corp. wrote:

> Hi,
>
> I imported an excel table (using read.csv) of Dow Jones monthly
> average closings where the first variable is a date as a character
> string such as "01OCT1928". How do I convert this to a date
> variable so I can plot monthly average closings against date using
> ggplot2?

?strptime # has the format specs that you can use with ...
?as.Date

--
David Winsemius, MD
West Hartford, CT

______________________________________________
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miguel manese

Re: Date formats

In reply to this post by Data Analytics Corp.-2

Hi Walt,

as.Date("01OCT1928", "%d%b%Y") works for me. See also ?strftime

Regards,

Jon

On Tue, Jun 19, 2012 at 8:00 PM, Data Analytics Corp.
<[hidden email]> wrote:

> Hi,
>
> I imported an excel table (using read.csv) of Dow Jones monthly average
> closings where the first variable is a date as a character string such as
> "01OCT1928". How do I convert this to a date variable so I can plot monthly
> average closings against date using ggplot2?
>
> Thanks,
>
> Walt
>
> ________________________
>
> Walter R. Paczkowski, Ph.D.
> Data Analytics Corp.
> 44 Hamilton Lane
> Plainsboro, NJ 08536
> ________________________
> (V) 609-936-8999
> (F) 609-936-3733
> [hidden email]
> www.dataanalyticscorp.com
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

arun kirshna

Re: Date formats

In reply to this post by Data Analytics Corp.-2

Hi,

Try this:
str1<-c("01OCT1928","02OCT1928","03OCT1928","04OCT1928")
strptime(str1,"%d%b%Y")
[1] "1928-10-01" "1928-10-02" "1928-10-03" "1928-10-04"

#or you can use this:

x<-as.Date(str1,format="%d%b%Y")
x
[1] "1928-10-01" "1928-10-02" "1928-10-03" "1928-10-04"

A.K.

----- Original Message -----
From: Data Analytics Corp. <[hidden email]>
To: [hidden email]
Cc:
Sent: Tuesday, June 19, 2012 8:00 AM
Subject: [R] Date formats

Hi,

I imported an excel table (using read.csv) of Dow Jones monthly average closings where the first variable is a date as a character string such as "01OCT1928". How do I convert this to a date variable so I can plot monthly average closings against date using ggplot2?

Thanks,

Walt

________________________

Walter R. Paczkowski, Ph.D.
Data Analytics Corp.
44 Hamilton Lane
Plainsboro, NJ 08536
________________________
(V) 609-936-8999
(F) 609-936-3733
[hidden email]
www.dataanalyticscorp.com

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Rui Barradas

Re: Date formats

In reply to this post by Data Analytics Corp.-2

Hello,

Try

as.Date("01OCT1928", format="%d%b%Y")
[1] "1928-10-01"

Note that though probably not a problem to you, this is locale specific.
In Portugal, the string corresponding to the same date would be
"01OUT1928". The variable to set using Sys.setlocale() would be LC_TIME.

For date formats the help page you want is

help("strptime")
?strptime

Hope this helps,

Rui Barradas

Em 19-06-2012 13:00, Data Analytics Corp. escreveu:

> Hi,
>
> I imported an excel table (using read.csv) of Dow Jones monthly average
> closings where the first variable is a date as a character string such
> as "01OCT1928". How do I convert this to a date variable so I can plot
> monthly average closings against date using ggplot2?
>
> Thanks,
>
> Walt
>
> ________________________
>
> Walter R. Paczkowski, Ph.D.
> Data Analytics Corp.
> 44 Hamilton Lane
> Plainsboro, NJ 08536
> ________________________
> (V) 609-936-8999
> (F) 609-936-3733
> [hidden email]
> www.dataanalyticscorp.com
>
> ______________________________________________
> [hidden email] mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

arun kirshna

Re: Date formats

In reply to this post by arun kirshna

Hi,

Since you need the monthly averages, I thought it might be helpful to have the month and the year alone in the plot when compared to the whole date.

Try this:
str2<-c("01OCT1928","01NOV1928","01DEC1928","01JAN1929")
x1<-as.Date(str2,format="%d%b%Y")
library(zoo)as.yearmon(x1)

[1] "Oct 1928" "Nov 1928" "Dec 1928" "Jan 1929"

A.K.

----- Original Message -----
From: arun <[hidden email]>
To: "[hidden email]" <[hidden email]>
Cc: R help <[hidden email]>
Sent: Tuesday, June 19, 2012 7:04 PM
Subject: Re: [R] Date formats

Hi,

Try this:
str1<-c("01OCT1928","02OCT1928","03OCT1928","04OCT1928")
strptime(str1,"%d%b%Y")
[1] "1928-10-01" "1928-10-02" "1928-10-03" "1928-10-04"

#or you can use this:

x<-as.Date(str1,format="%d%b%Y")
x
[1] "1928-10-01" "1928-10-02" "1928-10-03" "1928-10-04"

A.K.

----- Original Message -----
From: Data Analytics Corp. <[hidden email]>
To: [hidden email]
Cc:
Sent: Tuesday, June 19, 2012 8:00 AM
Subject: [R] Date formats

Hi,

I imported an excel table (using read.csv) of Dow Jones monthly average closings where the first variable is a date as a character string such as "01OCT1928". How do I convert this to a date variable so I can plot monthly average closings against date using ggplot2?

Thanks,

Walt

________________________

Walter R. Paczkowski, Ph.D.
Data Analytics Corp.
44 Hamilton Lane
Plainsboro, NJ 08536
________________________
(V) 609-936-8999
(F) 609-936-3733
[hidden email]
www.dataanalyticscorp.com

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

______________________________________________
[hidden email] mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.