# Linking to the SNOPT Library¶

The compiled SNOPT libraries are named libsnopt7 or libsnopt7_cpp. The Fortran and C subroutines (if enabled) of SNOPT are contained in libsnopt7, while the library libsnopt7_cpp contains Fortran, C, and C++ subroutines. If you need C++ support, you must link to libsnopt7_cpp with a C++ compiler, regardless of language used.

An example of how to compile and link a Fortran example with the SNOPT library:

>> gfortran -O -c myProb.f -o myProb.o
>> gfortran -O myProb.o  -o myProb -L$SNOPT/lib -lsnopt7  A Fortran example linking to the C++ library of SNOPT: >> gfortran -O -c myProb.f -o myProb.o >> g++ -O myProb.o -o myProb -L$SNOPT/lib -lsnopt7_cpp


A C++ example linking to the C++ library of SNOPT:

>> g++ -O -I$SNOPT/include -c myProb.cpp -o myProb.o >> g++ -O myProb.o -o myProb -L$SNOPT/lib -lsnopt7_cpp


Note

If utilizing shared libraries (.dylib/.so), the location of the library files must be added to DYLD_LIBRARY_PATH on macOS or LD_LIBRARY_PATH on Linux.

## Matlab Setup¶

To use SNOPT in the Matlab environment, identify the appropriate Matlab mex-file extension for your machine.

• Linux: .mexa64

• macOS: .mexmaci64

• Windows 64-bit Matlab: .mexw64

• Windows 32-bit Matlab: .mexa32

The location of the mex-file and the assocated Matlab m-files must be added to the Matlab path. There are 2 ways to do this:

1. use the setpath command at the Matlab terminal, or

2. go to Home -> Environment -> Set Path and add the location there.

To compile the Matlab mex-file from source, see Compiling for Matlab.

Before using the optimization libraries, you must set the environment variable <software name>_LICENSE, where <software name> is either “SNOPT” or “SQOPT”, to point to the license file, e.g.,

export SNOPT_LICENSE=\$HOME/licenses/snopt7.lic            % at the terminal
set SNOPT_LICENSE "C:\Users\me\snopt7.lic"                % at the Windows command line terminal

• On Windows systems, you need to have both the .dll file and the .lib file. The location of the library files (.lib and .dll) must be added to the system path. If you have admin privileges, then you can modify the path to add the location. Otherwise, place the library files in the same location as your calling executable.
• If the Windows SNOPT libraries are compiled as DLLs, you must also compile your programs with the /MD switch.