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From: Martin Schulz (Martin.Schulz_at_[hidden])
Date: 20070702 02:53:59
Hello,
that seems promising to me. Can I download that library somewhere on the
net to have a closer look at it?
I have to apologize that I probably wont find much time really soon,
though. At least I would like to get a better idea of it.
Yours,
Martin.
 Dr. Martin Schulz (schulz_at_[hidden]) Software Engineer Synopsys GmbH KarlHammerschmidtStr. 34 D85609 Dornach, Germany Phone: +49 (89) 99320203 http://www.synopsys.com > Original Message > From: boostbounces_at_[hidden] > [mailto:boostbounces_at_[hidden]] On Behalf Of Jeremy Bruestle > Sent: Freitag, 29. Juni 2007 22:10 > To: boost_at_[hidden] > Subject: [boost] Interest in tensor library? > > Greetings, > > I have developed a C++ tensor library using template > expressions which allows Einstein summation convention to be > used to describe mathematical operations on tensors in C++. > This allows a great simplification in syntax, while retaining > execution speeds identical to hand optimized C code in most > cases. An example of the syntax is: > > // Declare three rank 2 tensors (rank = # of dimensions) of > doubles with sizes of // 6 x 5, 6 x 10, and 10 x 5 respectively > > tensor<double, 2> A(6, 5); > tensor<double, 2> B(6, 10); > tensor<double, 2> C(10, 5); > > // Name three index variable to be used in what follows > index_variable<0> i; index_variable<1> j; index_variable<2> k; > > A[i][j] = 1.0; // Initialize A to all 1's B[i][j] = 4.5; // > Initalize B to all 4.5 > > boost::mt19937 rng; > C[i][j] = trand(rng); // Initalize C to uniform random > numbers 01 C[i][2] = 2.1; // Set row 2 to 2.1 C[2][i] = > 5.5; // Set col 2 to 5.5 C[2][2] = 0.0; // Zero out 2,2 > > A[i][j] = B[i][k] * C[k][j]; // Perform a matrix multiply > > /* The above line translates roughly as: > for(size_t i = 0; i < A.size<0>(); i++) > { > for(size_t j = 0; j < A.size<1>(); j++) > { > double total = 0.0; > for(size_t k = 0; k < B.size<1>(); k++) > total += B[i][k] * C[k][j]; > A[i][j] = total; > } > } > */ > An unlimited number of dimensions are supported, arbitrary > operations are allowed, and for cases where you wish to > perform other types of cumulative functions, such as finding > the maximum element, a syntax such as: A[i] = max(j, > B[i][j]); is allowed. There are lots of other interesting > features but I don't wish to make this email too long. > > As far as efficency, Intel's compiler builds every example > I've tried so far into code as good as doing the work by > hand. GCC does so for expressions of reasonably complexity, > and MSVC's optimizer does alright, but not nearly as well as > the others. > > I was interested in knowing what the interest level of > providing such a library as part of boost would be. I've > tried to adhere to the boost coding guidelines during the > construction. I've been using this library for over 6 months > myself for scientific computing. However, I've so far > avoiding sending a query to the boost mailing lists as the > procedures for submission and review seem quite daunting. > I'm usually crushingly busy, and I'm also especially bad at > documentation. Still, I thought I would float the idea to > guage interest, and also ask if anyone would be interested in > helping me through the process somewhat. > > Thank you for you time. > > Jeremy Bruestle > _______________________________________________ > Unsubscribe & other changes: > http://lists.boost.org/mailman/listinfo.cgi/boost >
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