On 2020-05-13 13:04 -0400, J C Nash wrote: > On 2020-05-13 11:28 a.m., Rasmus Liland wrote: > > > > I get another solution on my Linux i7-7500U > > > > > D %*% solve(D) > > [,1] [,2] > > [1,] 1.000000e+00 0 > > [2,] 8.881784e-16 1 > > > sessionInfo() > > BLAS: /usr/lib/libopenblasp-r0.3.9.so > > LAPACK: /usr/lib/liblapack.so.3.9.0 > > Note that my sessionInfo() gave > > R version 4.0.0 (2020-04-24) > Platform: x86_64-pc-linux-gnu (64-bit) > Running under: Linux Mint 19.3 > > Matrix products: default > BLAS: /usr/lib/x86_64-linux-gnu/blas/libblas.so.3.7.1 > LAPACK: /usr/lib/x86_64-linux-gnu/lapack/liblapack.so.3.7.1 > > So you have an older R but newer libraries, and the libblas is > a different one. > > Given the output is very similar, and within the rounding > margins of the double arithmetic, this looks like the > libraries are very slightly different. I suppose I should > be more inquisitive and try to seek out the changelog or other > description of the differences, but ... > > JN
Dear JN, I was thinking BLAS could be changed to OpenBLAS, apparently not: If I switch from OpenBLAS back to regular BLAS, the output is as expected ... I thought OpenBLAS should be a real alternative to BLAS in many cases, but not in this example? > D %*% solve(D) [,1] [,2] [1,] 1 1.110223e-16 [2,] 0 1.000000e+00 > sessionInfo() R version 3.6.3 (2020-02-29) Platform: x86_64-pc-linux-gnu (64-bit) Running under: Arch Linux Matrix products: default BLAS: /usr/lib/libblas.so.3.9.0 LAPACK: /usr/lib/liblapack.so.3.9.0 Best, Rasmus ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.