I am trying to compile a simple program, example.f90
program example
use dsyevd
implicit none
end program example
I am compiling using the command
gfortran -llapack example.f90
However this compilation returns the message
Fatal Error: Cannot open module file 'dsyevd.mod' for reading at (1): No such file or directory
dsyevd is a function in lapack. I have installed intel-mkl onto my computer which contains lapack95. Any advice on how to link my compile to these libraries would be hugely appreciated.
Thank you!
Lapack does not contain any module called dsyevd, so you cannot use it. It is a subroutine so it should be called.
Using -llapack is OK for the default Lapack pre-installed in your Linux distribution. For MKL you must use the appropriate options from the Link Advisor.
Related
I'm working on a problem for one of my computing courses and I was getting stuck in an error after trying to work through it for some time.
Specifically, I'm working on this Fortran routine:
program linsolve_sgtsv
implicit none
integer, parameter :: lda=10,ldb=lda,nrhs=1
real :: dl(lda-1),d(lda),du(lda-1),b(ldb,nrhs)
integer :: n,info
n = 10
dl(1:n-1) = 1+(1/11); d(1:n) = 2; du(1:n-1) = 1-(1/11)
b(1:n,1) = (/1,1,1,1,1,1,1,1,1,1/)
call sgtsv(n,nrhs,dl,d,du,b,ldb,info)
if (info==0) then
print *, '--- x is ----------------'
print '(g22.16)', b(1:n,1)
else
print *, 'info = ',info
end if
end program linsolve_sgtsv
This routine solves linear systems using gaussian elimination when the matrices are tridiagonal.
However, when I try to create a makefile using:
gfortran linsolve_sgtsv.f90 -o linsolve.f90
I get the following errors:
tmp/ccCiRHve.o: In function `MAIN__':
linsolve_sgtsv.f90:(.text+0x100): undefined reference to `sgtsv_'
collect2: error: ld returned 1 exit status
I can't find any direct duplicate. Many people have similar problems, but they usually know a bit more and your question is more basic.
The tridiagonal solver sgtsv() is not a Fortran built-in subroutine. It is provided in a library called LAPACK and many other implementations (e.g., MKL). That means you must tell the compiler it should include (link) that library.
That is done by adding -llapack (-l means "link" and lapack is the name of the library which is stored in a file called liblapack.so or liblapack.a) at the end of the compile command.
You must have his library installed in your computer for the link flag to work. In many Linux distributions it is included in the repositories.
The correct line would be
gfortran linsolve_sgtsv.f90 -o linsolve -llapack
If the library (liblapack.a or liblapack.so) is installed in some directory the compiler can't see, you must use
gfortran linsolve_sgtsv.f90 -o linsolve -L/path/to/liblapack -llapack
See also gfortran LAPACK "undefined reference" error and your compiler's manual for more.
Notice I did -o linsolve instead of -o linsolve.f90. It is a very bad idea to name your executable file with a .f90 extension. Only Fortran source files should be named .f90.
There will be more problems in your code. They will appear when you start to test it. For example, yoy do
(1/11)
this will not return the mathematical result of 1.0/11.0, it will return 0. Learn about integer division in Fortran. See Why are the elements of an array formatted as zeros when they are multiplied by 1/2 or 1/3? and Simple program, that only produce zeros, bug?
If you will find more problems after you can run your code, you can ask a new question.
I recommend to compile your programs with -g -fcheck=all -Wall to find more bugs and errors more easily.
I have been trying to use Matlab compiler SDK to packaging my Matlab program as C++ shared library in Debian system. I have got the folder including test.c, test.h, test.so (test is my Matlab program name), and I have installed the Matlab_runtime in the Debian system. I have set the variables LD_LIBRARY_PATH_ and _ XAPPLRESDIR_ as required in the readme.txt _ *( _ replace MCR_ROOT by the directory where the MATLAB Runtime is installed on the target machine.
(1) Set the environment variable XAPPLRESDIR to this value:
MCR_ROOT/v91/X11/app-defaults
(2) If the environment variable LD_LIBRARY_PATH is undefined, set it to the concatenation of the following strings:
MCR_ROOT/v91/runtime/glnxa64:
MCR_ROOT/v91/bin/glnxa64:
MCR_ROOT/v91/sys/os/glnxa64:
MCR_ROOT/v91/sys/opengl/lib/glnxa64_)*
.
I edit my main.cpp include test.h. when I try to compile the main.cpp use _ gcc main.cpp -o main_, I got the error as follows:
In file included from main.cpp:2:0:
test.h:15:22: fetal error: mclmcrrt.h: No such file or directory
#include "mclmcrrt.h"
I know that mclmcrrt.h is in the package of Matlab_runtime, it means I failed to link to the library of Matlab_runtime. Anybody knows what should I do to make my main.cpp compile successfully? I tried two days to work on how to connect to the Matlab_runtime library, but still failed. I am a beginner to linux. Great thanks if anyone can help.
This is a compilation problem, not linkage. Your compiler does not know where mclmcrrt.h is. Please help it find it by telling it where it is:
gcc -I<the_folder_where_mclmcrrt.h_lives_in> ...
I am trying to use FFTW3 with gfortran compiler included in the TDM-GCC-64 suite in Windows 7 platform.
I have downloaded "fftw-3.3.4-dll64.zip" from the following page:
http://www.fftw.org/install/windows.html
I also created a fortran module described in the following tutorial:
http://www.fftw.org/doc/Defining-an-FFTW-module.html
Now, I tried to compile the following fortrans program
program test
use FFTW3
implicit none
integer N
parameter(N=4)
integer*8 plan
double complex in, out
dimension in(N),out(N)
integer i
write(*,*) 'Input array:'
do i = 1,N,1
in(i) = dcmplx(float(i),float(i+1))
write(*,*) ' in(',i,') = ',in(i)
enddo
call dfftw_plan_dft_1d ( plan, N, in, out, FFTW_FORWARD, FFTW_ESTIMATE )
call dfftw_execute ( plan )
write(*,*) 'Output array:'
do i = 1,N,1
write(*,*) ' out(',i,') = ',out(i)
enddo
call dfftw_destroy_plan ( plan )
call dfftw_plan_dft_1d ( plan, N, out, in, FFTW_FORWARD, FFTW_ESTIMATE )
call dfftw_execute ( plan )
write(*,*) 'Output array after inverse FFT:'
do i = 1,N,1
write(*,*) ' ',N,' * in(',i,') = ',in(i)
enddo
call dfftw_destroy_plan ( plan )
end
I tried to compile but the a couple of error messages popped up:
undefined reference to dfftw_plan_dft_1d_'
undefined reference todfftw_execute_'
...
The command used for compiling is:
gfortran test.f90 -ffree-form -o test_fftw.exe
I searched web up and down but have not found solutions to the problem. Could anyone help me out here? Thanks!!!
You need to learn the basics of compiling and linking programs with GCC
This tutorial refers to the GCC C compiler, gcc, and C++ compiler, g++, but the principles are the same for the Fortran compiler, gfortran.
Your program invokes functions, like dfftw_plan_dft_1d that are not defined
in your code but in the fftw3 library. You must therefore tell gfortran
to link that library with your program, after it is compiled, or no definitions will be found for
these functions, and no executable can be built. Instead, the linkage
fails with the undefined reference errors you are seeing.
The command you have used to build the program:
gfortran test.f90 -ffree-form -o test_fftw.exe
attempts to compile and link the program in a single command. You can do this,
if you clearly understand the underlying separate processes of compiling
and linking. If you don't, you should follow the better practice of compiling first,
and if that is successful, then linking. The command you have used fails in
its linkage step because it does not tell the linker that the fftw3 library
is needed (or where to find it) so no attempt is made to find it and link it.
You say you have downloaded fftw-3.3.4-dll64.zip. I presume you have
unzipped it somewhere on your system. Let's say you unzipped it to C:\fftw-3.3.4-dll64.
You also say you have made an FFTW3 module that apparently is being used successfully.
In that case, compile your program first:
gfortran -c -o test.o test.f90
generating an object file test.o. The option -c tells gfortran to compile only,
and not to link. (You do not need to specify --ffree-form: the file-extension .f90
implies it).
Next, link the object file test.o with the fttw3 library, to make an executable
program test_fftw.exe:
gfortran -o test_fftw.exe test.o -LC:\fftw-3.3.4-dll64 -lfftw3-3
The linker option:
-LC:\fftw-3.3.4-dll64
tells the linker to add C:\fftw-3.3.4-dll64 (where you unzipped the package)
to the list of directories that it will search to find libraries. And the linker option -lfftw3-3 tells it to link a library that matches the identifier fftw3-3. On Windows, the GCC linker
will match a library identfier name with any of the filenames:
libname.a (a static library)
libname.dll (a shared library)
name.dll (also a shared library)
name.lib (an import library for a shared library)
So, since C:\fftw-3.3.4-dll64 contains the shared library libfftw3-3.dll,
the linker will identify it in that directory as the one required by -lfftw3-3
Now, unless there are other problems, you program will link and you will have
an executable test_fftw.exe, which will run, provided that libfftw3-3.dll
can be found, at runtime, in one of the places where the Windows
loader will look for it.
This is simple fortran90 program testing MPI.
I would like to compile it on MS Windows platform using MinGW64 Fortran and the known MS-MPI package.
However, it's not working due to missing "mpi.mod". When I replace the use mpi with include 'mpif.h', it's giving other errors (below).
Any help, please ? Does the MS-MPI suite cooperate with the MinGW gfortran ?
PS1:
Working with MS-MPI and MinGW gfortran is not an easy task, https://social.microsoft.com/Forums/en-US/245dcda4-7699-494f-bbe1-b76eb19e53da/linking-msmpi-with-mingw-gfortran?forum=windowshpcmpi
C:\Users\milias\Documents\Dirac\software\autocmake-devel\ms-mpi>gfortran -fno- range-check -c example.f90
mpif.h:344.38:
Included at example.f90:4:
PARAMETER (MPI_AINT=z'4c00043b')
1
Error: PARAMETER attribute of 'mpi_aint' conflicts with PARAMETER attribute at (1)
mpif.h:359.35:
Included at example.f90:4:
PARAMETER (MPI_ADDRESS_KIND=INT_PTR_KIND())
1
Error: Function 'int_ptr_kind' in initialization expression at (1) must be an intrinsic function
solved here, I apologize for the duplicate.
https://github.com/scisoft/autocmake/issues/85#issue-102874399
I would like to run a model is written Fortran90 under Ubuntu 14.04. I use gfortran 95 compiler (gfortran 4:4.8.2-1ubuntu6). The required netCDF libraries (netCDF C and Fortran netCDF) are installed as suggested in: http://www.unidata.ucar.edu/software/netcdf/docs/. The netcdf is built as shared library so libnetcdf.so and libnetcff.so files there are in the library directory. The libgfortran3 4.8.2-19ubuntu1 is installed for GNU fortran application linked against the shared library.
The LDFLAGS is set in the compiler_options.inc file by the following way:
INCDF=-I$(NCPATH)/include
LNCDF=-L$(NCPATH)/lib -lnetcdff -lnetcdf
LDFLAGS=$(INCDF) $(LNCDF)
When I compile the model I get the following messages:
/home/Beata/kid_a_setup/src/test_cases_2d.f90:1446: undefined reference to `_gfortran_runtime_error_at
Could someone explain me what causes the error and how I can fix it?
undefined reference to _gfortran_runtime_error_at means that the libgfortran library has not been found.
Either your system is misconfigured (can you compile, link and run a "Hello, world" program using gfortran?), or you are using the gcc command for linking instead of gfortran for linking. gcc does not know about the libgfortran library, where _gfortran_runtime_error_at is defined.