Mex error with GNU Scientific Library

Hi,

I've downloaded c++ code from the file exchange that implements the low discrepancy sequence generator by Niederreiter. Just like the instructions say in the Readme, I installed the GNU Scientific Library (GSL) and then tried to compile the code using the following command:

mex niederreiter.c -lgsl -lgslcblas -lm

However, this gives me the following errors:

niederreiter.c:28:27: error: gsl/gsl_qrng.h: No such file or directory
niederreiter.c: In function 'mexFunction':
niederreiter.c:80: error: 'gsl_qrng' undeclared (first use in this function)
niederreiter.c:80: error: (Each undeclared identifier is reported only once
niederreiter.c:80: error: for each function it appears in.)
niederreiter.c:80: error: 'q' undeclared (first use in this function)
niederreiter.c:196: error: 'gsl_qrng_niederreiter_2' undeclared (first use in this function)

    mex: compile of ' "niederreiter.c"' failed.

I'm perplexed why these files/directories can't be found, since the installation of GSL worked without any problems - I even ran make check, but it didn't find any issues.

Any idea what's wrong here? Thanks..

btw: I'm using MatlabR2012a and MatlabR2012b on MacOSX 10.6.8. XCode 3.2.6 is installed.

[Lokesh Ravindranathan]

I have not tried to install the package, but from the error message could you check if the header file (gsl_qrng.h)is present. It seems like the rest of the errors is because the symbols are defined in the header file and the main function does not have access to it.

[dave]

Yes, the header file is there. So I guess it probably has something to do with the path..

Answer 1

[Harsheel]

I think you need to provide the -I (capital i) flag along with MEX so that MEX can find the #include's present in niederreiter.c

    mex niederreiter.c -I<path_to_gsl_qrng.h> -lgsl -lgslcblas -lm

Note that the angular brackets are not required and that there should not be any space character between I and the path that you provide. More info. can be found here:

Mex_Options

[dave]

Harsheel, I followed your suggestion and modified the command to this:

mex niederreiter.c -I/usr/local/include/gsl -lgsl -lgslcblas -lm

However, that still gives me the same errors as before..

[Jan]

@dave: The file "gsl/gsl_qrng.h" is searched. You provide the folder "/usr/local/include/gsl". So is full path of the header file: "/usr/local/include/gsl/gsl/gsl_qrng.h" with "gsl" twice?

[dave]

@Jan Simon: Ah, that's my mistake - I thought it'd only search for "gsl_qrng.h". Thanks a lot for your help, now the compilation works fine.

[Li Fei]

Hi experts in Matlab and GSL, @dave @Jan Simon @Harsheel,

I am also using the GSL in Matlab. But I can not figure out how to call the GSL function in Matlab. GSL is for linux, however I am using Matlab in Windows. Could you please give some advice to me about the GSL calling from Matlab in Windows.

Thank you very much in advance.

PS: I'm using MatlabR2013a on Windows XP SP3.