LAPACK Archives

[Lapack] help with installation and DGELSY


I need some help with an installation issue and trying to figure out
an input parameter in one of the LAPACK subroutines. I am bugging you
at this email-id only because my question wasn't approved by the
moderator in the forum (,
my username is avinash ) and the other question was automatically
flagged as spam (I don't know why), so I couldn't post it. I
desperately need help.

I tried to install LAPACK in my computer (Mac OS X Mountain Lion
10.8.5) using BLAS provided in Accelerate Framework in Xcode Version
5.1.1 (5B1008). I used the example file for gfortran and just
modified these two lines following instructions here ( ).

FORTRAN  = gfortran -m64
BLASLIB      = -framework accelerate

After 'make', I got errors in the testing stage. These errors are at
the bottom of the email. According to this post, these errors are
because of Accelerate Framework ( ). It
appears that the compilation is successful, as I see a new liblapack.a
created. But if I get errors in Testing, is there another way to check
if my BLAS and LAPACK are working correctly ?

Also, I am trying to solve the overdetermined linear least squares
problem minimize ||Ax-B|| (A = rectangular matrix, with rows >
columns). I am trying to implement Matlab's mldivide in a Fortran code
using LAPACK's DGELSY subroutine.
However, one of the required inputs to subroutine dgelsy.f requires a
condition number input parameter "rcond" which is required to
determine the effective rank of A ( ). I will
be grateful for any ideas as to what a general value of rcond would
be, something used by Matlab or something that is computed or
something that is generally used. The example in ( ) does not say how "rcond" is
determined. This page ( )
suggests default value of rcond to be 100*EPSILON(1.0_WP). I don't
know what 1.0_WP means but I think it has something to do with working
precision, set by statements like interger, parameter :: wp =
kind(1.0). I think I should use double precision here, but I am not

I will be really grateful for your help !!



( cd BLAS/TESTING; make -f Makeblat1 )
gfortran -m64 -O2 -frecursive -c sblat1.f -o sblat1.o
gfortran  sblat1.o  \
        -framework accelerate  -o ../xblat1s
gfortran -m64 -O2 -frecursive -c dblat1.f -o dblat1.o
gfortran  dblat1.o  \
        -framework accelerate  -o ../xblat1d
gfortran -m64 -O2 -frecursive -c cblat1.f -o cblat1.o
gfortran  cblat1.o  \
        -framework accelerate  -o ../xblat1c
gfortran -m64 -O2 -frecursive -c zblat1.f -o zblat1.o
gfortran  zblat1.o \
        -framework accelerate  -o ../xblat1z
( cd BLAS; ./xblat1s > sblat1.out    ; \
          ./xblat1d > dblat1.out    ; \
          ./xblat1c > cblat1.out    ; \
          ./xblat1z > zblat1.out    )

Program received signal SIGSEGV: Segmentation fault - invalid memory reference.

Backtrace for this error:
#0  0x102c0efa2
#1  0x102c0f76e
#2  0x7fff90b16909
#3  0x7fff857123a4
#4  0x102c0714f
#5  0x102c074ab
#6  0x102c0753e
/bin/sh: line 1: 12127 Segmentation fault: 11  ./xblat1c > cblat1.out

Program received signal SIGSEGV: Segmentation fault - invalid memory reference.

Backtrace for this error:
#0  0x10e116fa2
#1  0x10e11776e
#2  0x7fff90b16909
#3  0x7fff85712748
#4  0x10e110d87
#5  0x10e11112b
#6  0x10e1111be
/bin/sh: line 1: 12130 Segmentation fault: 11  ./xblat1z > zblat1.out
make: *** [blas_testing] Error 139


Avinash Nayak,
PhD Candidate,
Berkeley Seismological Laboratory,
Department of Earth and Planetary Science,
University of California, Berkeley

<Prev in Thread] Current Thread [Next in Thread>
  • [Lapack] help with installation and DGELSY, Avinash Nayak <=

For additional information you may use the LAPACK/ScaLAPACK Forum.
Or one of the mailing lists, or