[R] need to delete by time, not date

[Adele_Thompson at cargill.com]

I am already using that to combine the date and time (I had it in the code, but took it out for the post to simplify it), but I still have the problem where I want to remove any time before 6am across all dates.

-----Original Message-----
From: clint at ecy.wa.gov [mailto:clint at ecy.wa.gov] 
Sent: Tuesday, May 10, 2011 10:15 AM
To: Thompson, Adele - Adele_Thompson at cargill.com
Cc: r-help at r-project.org
Subject: Re: [R] need to delete by time, not date

You may be happy using:

strptime(paste(Date,Time,sep=" "),"%m/%d/%y %H:%M")$hour

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On Tue, 10 May 2011, Schatzi wrote:

> I have a matrix where one column has a date and another column has a time. I
> need to delete all times before 6am. I had combined the Date and Time column
> into DateTime.
>
> Mat1:
> Weight     Date  Time
> 7.6 04/28/11 09:03
> 8.4 04/29/11 03:11
> 8.6 04/29/11 05:32
> 8.6 04/29/11 09:53
> 1.4 05/01/11 19:52
>
> I tried just picking up the time:
>
> as.POSIXct(Mat1$Time, format = "%H:%M")
>
> but this assigns the time value today's date.
>
> The final matrix should look like:
> Weight     Date  Time
> 7.6 04/28/11 09:03
> 8.6 04/29/11 09:53
> 1.4 05/01/11 19:52
>
>
> -----
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