<div dir="ltr">Thanks! That's about 2-3x faster. I wasn't familiar with stack/unstack. Now I have another tool.<div><br></div><div>Cheers,</div><div>e.</div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div><br></div>----<div><br><b>Eric Archer, Ph.D.</b></div><div><b><br></b>Southwest Fisheries Science Center (NMFS/NOAA)<br>8901 La Jolla Shores Drive<br>La Jolla, CA 92037 USA<br>858-546-7121 (work)<br>858-546-7003 (FAX)<br><br><span style="font-size:12.8px">Marine Mammal Genetics Group: </span><a href="http://swfsc.noaa.gov/mmtd-mmgenetics" style="font-size:12.8px" target="_blank" rel="nofollow" link="external">swfsc.noaa.gov/mmtd-mmgenetics</a><br style="font-size:12.8px"><span style="font-size:12.8px">GitHub: </span><a href="https://github/ericarcher" style="font-size:12.8px" target="_blank" rel="nofollow" link="external">github/ericarcher</a><br><br>&</div><div><br><div>Adjunct Professor, Marine Biology</div><div>Scripps Institution of Oceanography</div><div>University of California, San Diego</div><div><a href="http://profiles.ucsd.edu/frederick.archer" target="_blank" rel="nofollow" link="external">http://profiles.ucsd.edu/frederick.archer</a><br></div><div><br></div><br>"<i>The universe doesn't care what you believe.<br> The wonderful thing about science is that it<br> doesn't ask for your faith, it just asks<br> for your eyes.</i>" - Randall Munroe<br><br>"<i>Lighthouses are more helpful than churches.</i>"<br> - Benjamin Franklin<br><br> "<i>...but I'll take a GPS over either one.</i>"<br> - John C. "Craig" George </div></div></div></div></div></div></div></div></div></div></div></div></div></div>
<br><div class="gmail_quote">On Wed, Nov 23, 2016 at 11:11 AM, nachti [via R] <span dir="ltr"><<a href="/user/SendEmail.jtp?type=node&node=4726779&i=0" target="_top" rel="nofollow" link="external">[hidden email]</a>></span> wrote:<br><blockquote style='border-left:2px solid #CCCCCC;padding:0 1em' class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Try this:
<br><br>t1 <- dt[, unlist(.SD), by = id]
<br>t(unstack(t1, form = V1 ~ id))
<br><br>(I think you get done with the colnames yourself ...)
<br><br>Cheers,
<br>~g
<br>
<br>
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