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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>I just obtained the latest release of data.table, and immediately went to see what’s new. The help on := was just what I was looking for. It cleared up things nicely for me, the RHS/LHS issue was very helpful, and the examples were the usual good stuff--simple, and they get a variety of ideas across succinctly. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Minor note:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'> DT[a>"A",b:=d*2L] # subassign to b using d where a>"A"<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>does not work: a is a factor, not character.<o:p></o:p></span></p></div></body></html>