[R] need more help.... Re: iterating over a data frame the R way?

[donahchoo at me.com]

Hum.  data.frame was left off.  Trying again...

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On Jan 1, 2010, at 10:20 AM, donahchoo at me.com wrote:

> Okay, I don't know if I'm blocking because of my other programming  
> language experience of if I'm just being dense.
>
> I have a data.frame with high,open,low,last,day, and start_time time  
> columns.  What I want to do is get all the rows with the same day  
> and process each of those columns.  If I was able to run a query  
> against the data.frame I would be want something like:
>
> result = all the rows where the day is equal to 2007-12-05
>
> Then I would want get max(result["high"]), min(result["low"])
>
> How do I do this?  I tired sqldf, but its complaining about  
> libtcl0.5.8 not being found.  I'm on OS X 10.5.8 and haven't yet  
> tired to install a new version of tcl in /usr/local.
>
> Here's the dataframe:
>
>
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