Le 20/03/2018 à 12:10, akshay kulkarni a écrit :
dear members,
I came to know from stackoverflow that the
following references a row in a matrix in C++:
M[2] references 2nd row of the Matrix.
SO is too big to check this assertion by ourself. Do you have a link?
I am using Rcpp to write C++ code in R.
However, I ended up with the following inconsistency:
> M
x y z
[1,] 1 1 1
[2,] 2 2 2
[3,] 3 3 3
[4,] 4 4 4
[5,] 5 5 5
[6,] 6 6 6
> cppFunction('IntegerVector tccp3(IntegerMatrix M) { IntegerVector x = M[2];
return x;}')
Try
cppFunction('IntegerVector tccp3(IntegerMatrix M) { IntegerVector x = M(2,_);
return x;}')
Best,
Serguei.
> tccp3(M)
[1] 0 0 0
> cppFunction('IntegerVector tccp4(IntegerMatrix M) { IntegerVector x = M[1];
return x;}')
> tccp4(M)
[1] 0 0
tccp3 should return (3,3,3) and tccp4 should return (2,2,2). Can you please
shed light on what is going on?
very many thanks for your time and effort....
Yours sincerely,
AKSHAY M KULKARNI
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