<div>Can anyone give me an example of how to use hash table to do joins? For example, </div>
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<div>a <- matrix(c(1:14), ncol = 2, dimnames = list(NULL, c('id','value')))</div>
<div>b <- matrix(0, ncol = 2, nrow = 30, dimnames = list(NULL, c('id', 'value')))</div>
<div>b[,1] <- sample(c(1:7), size = 30, replace = T)</div>
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<div>I need to populate b[,2] with the values in a[,2] by matching b[,1] and a[,1]. Does anyone know how I can do this by using hash table in Rcpp? Thank you.</div>
<div><br clear="all"><br>-- <br>Aileen L.</div>
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<font color="#993399">Being happy doesn't mean you're perfect. It just means you've decided to look beyond the imperfectio</font><font color="#cc33cc">ns- <a style="PADDING-BOTTOM:0px;MARGIN:0px;PADDING-LEFT:0px;PADDING-RIGHT:0px;TEXT-DECORATION:none;PADDING-TOP:0px" href="http://www.boardofwisdom.com/default.asp?topic=1010&search=K%2EB+Indiana+%28age+14%29" target="_blank">K.B Indiana (age 14)</a></font></h2>
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