# FORTRAN Wrapper¶

For FORTRAN, there are two fundamental choices. Choose one option:

• [Recommended] For FORTRAN 95 and newer, compile a static library of CoolProp and link it with FORTRAN code following the instructions here: F95 and newer
• For FORTRAN 77 and newer, call a shared library of CoolProp using the instructions here: F77 and newer

## Common Requirements¶

Compilation of the Fortran wrapper requires a few common wrapper pre-requisites

## Compilers¶

On linux, you need gcc and gfortran, which are easy to install using your package manager.

On windows, the most reliable mixed compilation seems to be using the gfortran/gcc combination from MinGW-w64, whose installer allows you to install different versions of GCC, typically up to the last one. Version 5.3.0 is the one used as of February 10, 2016:

>C:\>gfortran --version
GNU Fortran (x86_64-posix-seh-rev0, Built by MinGW-W64 project) 5.3.0
Copyright (C) 2015 Free Software Foundation, Inc.

GNU Fortran comes with NO WARRANTY, to the extent permitted by law.
You may redistribute copies of GNU Fortran
under the terms of the GNU General Public License.

>C:\>g++ --version
g++ (x86_64-posix-seh-rev0, Built by MinGW-W64 project) 5.3.0
Copyright (C) 2015 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.


Warning

gfortran in GCC version 5.1 has a bug preventing to open external files (a segmentation error is prompted), which makes this version almost useless for fortran users.

On OSX, the default compiler that comes with XCode is clang, gcc and g++ at the command prompt are just aliases to clang. See for instance:

$gcc --version Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1 Apple LLVM version 5.1 (clang-503.0.40) (based on LLVM 3.4svn) Target: x86_64-apple-darwin13.3.0 Thread model: posix  The most reliable mixed compilation on linux seems to be with the true-gcc/g++ toolchain rather than clang+gfortran. To install gcc/g++, install gcc/g++ using homebrew with something like: brew install gcc-4.9  where you can change 4.9 to the most up to date version. Search braumeister for the most recipe for gcc. Looks like gcc also works. ## FORTRAN 95/2003 using ISO_C_BINDING¶ ### Build static library of CoolProp¶ On all platforms, start in root folder of recursively-cloned CoolProp repo. 1. On linux, do: mkdir build && cd build mkdir gccstatic && cd gccstatic cmake ../.. -DCOOLPROP_STATIC_LIBRARY=ON -DCOOLPROP_EXTERNC_LIBRARY=ON -DCMAKE_VERBOSE_MAKEFILE=ON cmake --build .  2. On Windows, the call to CMake should be done using the MinGW generator, but otherwise the procedure is the same: mkdir build && cd build mkdir gccstatic && cd gccstatic cmake ../.. -G "MinGW Makefiles" -DCOOLPROP_STATIC_LIBRARY=ON -DCOOLPROP_EXTERNC_LIBRARY=ON -DCMAKE_VERBOSE_MAKEFILE=ON cmake --build .  3. On OSX, cmake must use the true, real, gcc/g++ compiler (not clang). Thus you must do something like this to make sure that it finds the right (true) gcc/g++ (see above): mkdir build && cd build mkdir gccstatic && cd gccstatic cmake ../.. -DCOOLPROP_STATIC_LIBRARY=ON -DCOOLPROP_EXTERNC_LIBRARY=ON -DCMAKE_C_COMPILER="/usr/local/bin/gcc-4.9" -DCMAKE_CXX_COMPILER="/usr/local/bin/g++-4.9" -DCMAKE_VERBOSE_MAKEFILE=ON cmake --build .  If you are using a different version of gcc, change the version number for g++ and gcc This will generate the file libCoolProp.a which is a GCC static library that can be linked with GCC/GFORTRAN code. Copy this .a file into the directory with the coolprop FORTRAN example cool_fortran_bind.f90: !Example calculates density of saturated liquid propane at 300 K: program simple USE cpinterface implicit none !Initialize the variables used in the example double precision T, Q, dens1 character(LEN=32) fluid, out1, n1, n2 T = 300 ! Temperature [K] Q = 0 ! Quality [-] out1 = "D"//CHAR(0) ! String with of the output Property n1 = "T"//CHAR(0) ! String with of the input Property #1 n2 = "Q"//CHAR(0) ! String with of the input Property #2 fluid = "Propane"//CHAR(0) ! String with the fluid name dens1 = PropsSI(out1, n1, T, n2, Q, fluid) Print *, dens1 end program simple  with the interface file cpinterface.f90: MODULE CPINTERFACE INTERFACE FUNCTION PropsSI (output, name1, prop1, name2, prop2, fluidname) BIND(C, NAME='PropsSI') use iso_c_binding real(C_DOUBLE) :: PropsSI character(KIND=c_char) :: output(*) character(c_char) :: name1(*) real(C_DOUBLE), VALUE :: prop1 character(c_char) :: name2(*) real(C_DOUBLE), VALUE :: prop2 character(kind=c_char) :: fluidname(*) END FUNCTION PropsSI END INTERFACE END MODULE CPINTERFACE  In order to link all the files together, do: gfortran -c -Wall cpinterface.f90 cool_fortran_bind.f90 gcc -o main *.o libCoolProp.a -lstdc++ -ldl -lgfortran -lm main  On windows, you can leave off the -ldl and also the -lm might not be required. On OSX, you must do the linking stage with true gcc so that it finds the right standard library. Or alternatively, provide the full path to the libstdc++ static library and link with gfortran with something like: gfortran -o main *.o libCoolProp.a /usr/lib/libstdc++.a -ldl  Warning You MUST(!!!) put the -lstdc++ standard libary after libCoolProp.a. Same thing if you compile the fortran to object file, static library must always be at the end. ## FORTRAN77¶ ### Pre-Compiled Binaries¶ ### Run¶ Use the sample file example.for given by: double precision T, Q, D, h, s character(LEN=32) Ref,Output, Name1, Name2 double precision outVal, Prop1, Prop2 T = 285 Q = 0 D = 1250; Output = "P"//CHAR(0) Name1 = "T"//CHAR(0) Prop1 = T Name2 = "Q"//CHAR(0) Prop2 = Q Ref = "R134a"//CHAR(0) outval = 9999999 write(*,*) "Saturation pressure for R134a: " call propssi(Output, Name1, Prop1, Name2, Prop2, Ref, outVal) write(*,*) "Result was: ", outVal/1e5, " bar" write(*,*) "-----------------------------------------------" end program  Place the shared library and the sample file in the same directory. On linux, build and run the example.for file with: gfortran -g -o example example.for -L. -lCoolProp LD_LIBRARY_PATH=$PWD:\$LD_LIBRARY_PATH example


On windows, the current folder is always searched for DLL, so you can just do:

gfortran -g -o example example.for -L. -lCoolProp
example