GMP is an essential external library for CoCoALib: a sufficiently
recent version of GMP must be present to permit compilation of CoCoALib.
The CoCoALib classes
BigRat are simply wrappers for
the underlying GMP types.
At the moment CoCoALib does not require the C++ interface to GMP, however if you wish to combine CoCoALib with the external library Normaliz then the C++ interface to GMP must also be present.
It is common for Linux computers to have the GMP library already installed; the CoCoALib configuration script will check for this, and will give an error message if it cannot be found.
If you do need (or want) to build the GMP library yourself, you can get it from
Note that CoCoALib expects GMP release 5.0.0 or later.
During configuration of GMP we recommend giving the option
even though this is not strictly necessary for CoCoALib. We also
recommend building the static libraries (in GMP-6.1.0 both static and
shared libraries are built by default, but check the documentation of
the version of GMP which you obtained).
If you have the relevant permissions (and you want to), you can
"install" the GMP library by running
make install. If you do
install the GMP library, it is important that you run the privileged
ldconfig to properly register the new shared libraries.
If you do not install the library then make a note of the full path
to where the file
libgmp.a is (on my computer it is in an
invisible subdirectory called
.libs), as you must specify this
when configuring CoCoALib.
Then configure and compile CoCoALib by typing (but without the
--with-libgmp if GMP is properly installed).
cd CoCoALib-0.99 ./configure --with-libgmp=<your_path_to>/libgmp.a make
A future version of CoCoALib may use the C++ interface to GMP, but that it not imminent.
Strictly the parts of CoCoALib which compute with small finite fields do not need the GMP library; nevertheless we chose not to permit compilation without GMP.
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