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<p style="margin-top:0; margin-bottom:0">dear members, </p>
<p style="margin-top:0; margin-bottom:0"> I came to know from stackoverflow that the following references a row in a matrix in C++:</p>
<p style="margin-top:0; margin-bottom:0">M[2] references 2nd row of the Matrix.</p>
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<p style="margin-top:0; margin-bottom:0">I am using Rcpp to write C++ code in R.</p>
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<p style="margin-top:0; margin-bottom:0">However, I ended up with the following inconsistency:</p>
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<div>> M</div>
<div> x y z</div>
<div>[1,] 1 1 1</div>
<div>[2,] 2 2 2</div>
<div>[3,] 3 3 3</div>
<div>[4,] 4 4 4</div>
<div>[5,] 5 5 5</div>
<div>[6,] 6 6 6</div>
<div>> cppFunction('IntegerVector tccp3(IntegerMatrix M) { IntegerVector x = M[2]; return x;}')</div>
<div>> tccp3(M)</div>
<div>[1] 0 0 0</div>
<div>> cppFunction('IntegerVector tccp4(IntegerMatrix M) { IntegerVector x = M[1]; return x;}')</div>
<div>> tccp4(M)</div>
<div>[1] 0 0</div>
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<div>tccp3 should return (3,3,3) and tccp4 should return (2,2,2). Can you please shed light on what is going on?</div>
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<div>very many thanks for your time and effort....</div>
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<div>Yours sincerely,</div>
<div>AKSHAY M KULKARNI</div>
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