Eigen is a C++ template library for linear algebra: vectors, matrices, and related algorithms. It is versatile, fast, elegant and works on many platforms.
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EIGEN_DEFAULT_TO_ROW_MAJOR is fully supported and tested. Several important fixes were made for row-major matrices. Support of several algorithms for mixed fixed-dynamic size matrices were fixed. EIGEN_DONT_ALIGN was fixed: now it really disables vectorization. QNX's QCC compiler is supported. LU is fixed when used with MPFR. ICC compiler support was fixed. Compilation fixes were made for computeInverse() on expressions. A gap in a unit-test was fixed. Improvements to benchmarking code were backported. Documentation fixes were made.