f77blas.h not found (Ubuntu, Octave)

[catch22]

The fix I found was to install libopenblas-dev and replace the include statement in blksdp.h to #include <openblas/f77blas.h> (cf. 44fe8cc).

[nvitucci]

Since there are many files having the same problem, I found it easier to add a flag -I/usr/include/openblas in the install_sedumi.m script (in the need_rebuild/ISOCTAVE section).

This worked on Fedora, but I am not sure about other systems (hence why I am not 100% sure this is PR-worthy). What do you think?

[siko1056]

sedumi/blksdp.h

Lines 40 to 47 in d559b73

	#ifdef OCTAVE
	#include "f77blas.h"
	#define FORT(x) BLASFUNC(x)
	#else
	#include "blas.h"
	#define FORT(x) FORTRAN_WRAPPER(x)
	typedef ptrdiff_t blasint;
	#endif

f77blas.h is a pure OpenBLAS header. If you are using a different BLAS/LAPACK implementation, SeDuMi is not likely to work with Octave today. Unfortunately, Octave does not distribute the BLAS/LAPACK function prototypes in the blas.h header, like Matlab does. Octave currently only exposes a subset of these function in the C++ headers lo-blas-proto.h and lo-lapack-proto.h that cannot be included for compilation with mex (only C). This made the change 44fe8cc necessary, as many Octave users use OpenBLAS anyway.

The change proposed by @catch22 would break the current Octave 5.1.0 Windows installations. The header f77blas.h is deployed in the C:\Octave\Octave-5.1.0.0\mingw64\include directory.

The change proposed by @nvitucci is not the cleanest solution to hardcode a directory, but it might cover several default configured GNU/Linux distributions.

You can provide a PR @nvitucci and if there are no different opinions, it is likely to get merged.

[nvitucci]

Thanks @siko1056 , will do. I think we can add this as a parameter in the install script, so that the exact location will not be hardcoded.

[nvitucci]

@siko1056 Done on #49.

[catch22]

The hardcoded directory does not seem to work with Ubuntu - see the error log at https://travis-ci.org/catch22/quantbox/builds/641260667#L968 and the travis config at https://github.com/catch22/quantbox/blob/master/.travis.yml. Please let me know if you need any further information.

[siko1056]

Do you rely for current software development on Ubuntu (14.04 LTS) "Trusty Tahr", which ran out of standard support last year and OpenBLAS 0.2.8 from 2013?

https://github.com/catch22/quantbox/blob/4c07cb8090996ecdee8c0b69aecc7c8e9750ea3f/.travis.yml#L2

My impression is, that the OpenBLAS headers were not installed in Ubuntu 14.04 https://launchpad.net/ubuntu/trusty/amd64/libopenblas-dev/0.2.8-6ubuntu1

Can you verify this on an Ubuntu 14.04 machine with "libopenblas-dev" installed, what is the output of

find /usr -iname "f77blas.h"

You can easily upgrade your Travis CI check to a more recent Ubuntu (16.04 LTS) "Xenial Xerus" for which this path will work (as for almost any other current Linux distribution).

https://packages.ubuntu.com/xenial/amd64/libopenblas-dev/filelist

[catch22]

Yikes, great catch. Thanks!

[siko1056]

You're welcome, thanks for using this repo and reporting issues. Can this item be closed again?

https://travis-ci.org/catch22/quantbox/builds/641277190#L990

Off-topic: "quantbox" looks interesting to me 😉