Re: [ublas] Problem with nested products

Subject: Re: [ublas] Problem with nested products
From: Umut Tabak (u.tabak_at_[hidden])
Date: 2010-12-20 11:55:58

On 12/20/2010 05:49 PM, Michael Wand wrote:
> #include<boost/numeric/ublas/matrix.hpp>
> #include<boost/numeric/ublas/vector.hpp>
> #include<boost/numeric/ublas/io.hpp>
>
> namespace ublas = boost::numeric::ublas;
>
> // Take a matrix A and a row vector B
> void UBlasStuff(ublas::matrix<double>  A,ublas::matrix<double>  B) {
> 	ublas::matrix<double>  BTrans = ublas::trans(B);
> 	
> // the next two lines work
> 	ublas::matrix<double>  intermediate_result = ublas::prod(B,A);
> 	ublas::matrix<double>  result = ublas::prod(intermediate_result,BTrans);
>
> // the next two lines do not compile if uncommented	
> ///	ublas::matrix<double>  result_direct =
> ///               ublas::prod(B,ublas::prod(A,BTrans));
> 	
> }
>
> int main(int argc,char** argv) {
> 	ublas::matrix<double>  A(3,3); // uninitialized since we're looking for a
> 	ublas::matrix<double>  B(1,3); // compilation error, not a runtime error
> 	UBlasStuff(A,B);
> 	return 0;
> }
>
>    
Compiles fine here, which version are you using?

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