<div dir="ltr">I'm a little puzzled by your question. Could you use a reference instead of instantiating a new copy?</div><div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Feb 19, 2013 at 3:19 PM, Ken Williams <span dir="ltr"><<a href="mailto:Ken.Williams@windlogics.com" target="_blank">Ken.Williams@windlogics.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div class="im"><br>
<br>
> -----Original Message-----<br>
> From: Yan Zhou [mailto:<a href="mailto:zhouyan@me.com">zhouyan@me.com</a>]<br>
> Sent: Tuesday, February 19, 2013 5:10 PM<br>
> To: Dirk Eddelbuettel<br>
> Cc: Ken Williams; <a href="mailto:rcpp-devel@lists.r-forge.r-project.org">rcpp-devel@lists.r-forge.r-project.org</a><br>
> Subject: Re: [Rcpp-devel] Efficient DataFrame access by row & column<br>
><br>
> The most inefficient part I see is the creation of a new NumericVector inside<br>
> the inner most loop. You copied each column n times, of which n-1 times are<br>
> unnecessary.<br>
<br>
</div>That's what I suspected. So is there no way to access elements of a DataFrame without copying columns to a new vector first?<br>
<span class="HOEnZb"><font color="#888888"><br>
-Ken<br>
</font></span><div class="im HOEnZb"><br>
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