reading in time series

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reading in time series

tluedeke
This is causing me great consternation, and I've spent too much time floundering around on it.

My data is in the form of columns in Excel, with the first column being in m/dd/yyyy hh:mm format.  The spreadsheet is complicated (headers, merged cells, lines w/o data); so I've tried various ways of exporting the data into a text file for the R processing - CSV, spaced, etc.  For example:

3/23/2010 20:55  -0.106559999  -0.121454561  -0.120300002  -0.111680001  -0.122429997
3/23/2010 21:25  -0.099166997  -0.114189997  -0.112879999  -0.104647976  -0.114720002
.
.

- or -

3/23/2010 20:55,  -0.106559999,  -0.121454561,  -0.120300002,  -0.111680001,  -0.122429997
3/23/2010 21:25,  -0.099166997,  -0.114189997,  -0.112879999,  -0.104647976,  -0.114720002
.
.

I can't seem to get R to recognize this data as a time/data column in m/dd/yyyy hh:mm format followed by columns of data.  There was a post on an analogous topic a couple of years ago, but none of the proposed (and quite complicated) solutions seemed to work for me.

Anyone know how to handle this?
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Re: reading in time series

Mogguy
You have to tell R that a column has date/time content. Here is an example:

test<-"3/23/2010 20:55" #this is your format
as.POSIXct(test, format="%m/%d/%Y %H:%M") #with the format parameter you
tell R how to interpret your data

_______________________
Moritz Grenke
http://www.360mix.de

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Re: reading in time series

jholtman
In reply to this post by tluedeke
Is this what you are trying to do:

> x <- read.table(textConnection("3/23/2010 20:55,  -0.106559999,  -0.121454561,  -0.120300002,  -0.111680001,-0.122429997
+ 3/23/2010 21:25,  -0.099166997,  -0.114189997,  -0.112879999,
-0.104647976,-0.114720002"), sep = ',', as.is = TRUE)
> closeAllConnections()
> x
               V1        V2         V3       V4         V5       V6
1 3/23/2010 20:55 -0.106560 -0.1214546 -0.12030 -0.1116800 -0.12243
2 3/23/2010 21:25 -0.099167 -0.1141900 -0.11288 -0.1046480 -0.11472
> str(x)
'data.frame':   2 obs. of  6 variables:
 $ V1: chr  "3/23/2010 20:55" "3/23/2010 21:25"
 $ V2: num  -0.1066 -0.0992
 $ V3: num  -0.121 -0.114
 $ V4: num  -0.12 -0.113
 $ V5: num  -0.112 -0.105
 $ V6: num  -0.122 -0.115
> # convert to POSIXct
> x$V1 <- as.POSIXct(x$V1, format = "%m/%d/%Y %H:%M")
> x
                   V1        V2         V3       V4         V5       V6
1 2010-03-23 20:55:00 -0.106560 -0.1214546 -0.12030 -0.1116800 -0.12243
2 2010-03-23 21:25:00 -0.099167 -0.1141900 -0.11288 -0.1046480 -0.11472
> str(x)
'data.frame':   2 obs. of  6 variables:
 $ V1: POSIXct, format: "2010-03-23 20:55:00" "2010-03-23 21:25:00"
 $ V2: num  -0.1066 -0.0992
 $ V3: num  -0.121 -0.114
 $ V4: num  -0.12 -0.113
 $ V5: num  -0.112 -0.105
 $ V6: num  -0.122 -0.115
>


On Thu, Jan 20, 2011 at 3:04 AM, tluedeke <[hidden email]> wrote:

>
> This is causing me great consternation, and I've spent too much time
> floundering around on it.
>
> My data is in the form of columns in Excel, with the first column being in
> m/dd/yyyy hh:mm format.  The spreadsheet is complicated (headers, merged
> cells, lines w/o data); so I've tried various ways of exporting the data
> into a text file for the R processing - CSV, spaced, etc.  For example:
>
> 3/23/2010 20:55  -0.106559999  -0.121454561  -0.120300002  -0.111680001
> -0.122429997
> 3/23/2010 21:25  -0.099166997  -0.114189997  -0.112879999  -0.104647976
> -0.114720002
> .
> .
>
> - or -
>
> 3/23/2010 20:55,  -0.106559999,  -0.121454561,  -0.120300002,  -0.111680001,
> -0.122429997
> 3/23/2010 21:25,  -0.099166997,  -0.114189997,  -0.112879999,  -0.104647976,
> -0.114720002
> .
> .
>
> I can't seem to get R to recognize this data as a time/data column in
> m/dd/yyyy hh:mm format followed by columns of data.  There was a post on an
> analogous topic a couple of years ago, but none of the proposed (and quite
> complicated) solutions seemed to work for me.
>
> Anyone know how to handle this?
> --
> View this message in context: http://r.789695.n4.nabble.com/reading-in-time-series-tp3225481p3225481.html
> Sent from the R help mailing list archive at Nabble.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.
>



--
Jim Holtman
Data Munger Guru

What is the problem that you are trying to solve?

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