I'm sorry this is more of a numerix (or even a lapack) problem than a direct SciPy problem. I've been trying to make up Numeric & numarray on a Linux opteron box, using atlas/lapack. Numeric eventually seemed to work and pass its tests, though I had to compile ATLAS and LAPACK with -fPIC. ATLAS passed sanity tests. numarray-1.3.3 is proving more difficult. Worked out that installing numarray with python setup.py config --use_lapack install --gencode is the (undocumented) way to link to external libraries. No compilation or installation problems, but when I ran testall.test() found 3 problems to do with determinants (messages at end). Sign of 2nx2n determinants seems to be wrong. e.g. import numarray.linear_algebra.LinearAlgebra2 as la2 import numarray.numeric as num a = num.array([[1.,2.], [3.,4.]]) print la2.determinant(a) -> gives 2.0 (should be -2) but 2n+1 x2n+1 seems OK. c = num.array([[1,0,0],[0,1.,-2.], [0,3.,4.]]) print la2.determinant(b) -> gives (correctly) 10.0 Default installation w/o lapack gives the right answers. So I tested lapack by compiling *all* the lapack stuff, (including the test suite) instead of just the lapacklib i.e. I did make all instead of make lapacklib This gave 'major' (i.e. order 10^16) errors in cgd.out, csep.out, ded.out, dgd.out, sgd.out, ssep.out,ssvd.out, zgd.out. Now [cdsz]gd.out errors are apparently expected -- see http://web.mit.edu/lapack/www/faq.html#1.24 But errors in ded.out,ssep.out, ssvd.out may be more serious. Are they causing the incorrect-sign determinants? Puzzled. --George Nurser. compilation method --------------------------- ATLAS. make xconfig ./xconfig -F f '-fPIC -fomit-frame-pointer -O -m64 -fno-second-underscore' -F c '-fPIC -fomit-frame-pointer -O -mfpmath=387 -m64' -F m '-fPIC -fomit-frame-pointer -O -mfpmath=387 -m64' -b /usr/lib/libblas.a make install arch=Linux_HAMMER64SSE2 LAPACK. use ATLAS blas; OPTS/NOOPT following http://www.scipy.org/mailinglists/mailman?fn=scipy-user/2005-February/ 004066.html so in make.inc OPTS = -funroll-all-loops -O3 -m64 -fno-second-underscore -fPIC NOOPT = -m64 -fno-second-underscore -fPIC BLASLIB = .....ATLAS/lib/Linux_HAMMER64SSE2/f77blas.a lapack errors ------------------ grep ail * cgd.out: Matrix types (see CDRGEV for details): cgd.out: CGV drivers: 63 out of 1092 tests failed to pass the threshold csep.out: Matrix types (see xDRVST for details): csep.out: CST drivers: 1 out of 11664 tests failed to pass the threshold ded.out: Matrix types (see DDRVES for details): ded.out: DES: 1 out of 3270 tests failed to pass the threshold ded.out: Matrix types (see DDRVSX for details): ded.out: DSX: 1 out of 3500 tests failed to pass the threshold dgd.out: Matrix types (see DDRGEV for details): dgd.out: DGV drivers: 8 out of 1092 tests failed to pass the threshold dgd.out: DXV drivers: 200 out of 5000 tests failed to pass the threshold sgd.out: Matrix types (see SDRGEV for details): sgd.out: SGV drivers: 8 out of 1092 tests failed to pass the threshold sgd.out: SXV drivers: 37 out of 5000 tests failed to pass the threshold ssep.out: Matrix types (see SCHKST for details): ssep.out:Test performed: see SCHKST for details. ssep.out: SST: 2 out of 4662 tests failed to pass the threshold ssep.out: Matrix types (see xDRVST for details): ssep.out: SST drivers: 1 out of 14256 tests failed to pass the threshold ssvd.out: Matrix types (see xCHKBD for details): ssvd.out: SBD: 1 out of 5510 tests failed to pass the threshold zgd.out: Matrix types (see ZDRGEV for details): zgd.out: ZGV drivers: 62 out of 1092 tests failed to pass the threshold zgd.out: ZXV drivers: 24 out of 5000 tests failed to pass the threshold