Function: _def_nbthreads
Class: default
Section: default
C-Name: sd_nbthreads
Prototype:
Help:
Doc: Number of threads to use for parallel computing.
 The exact meaning an default depend on the \kbd{mt} engine used:

 \item \kbd{single}: not used (always one thread).

 \item \kbd{pthread}: number of threads (unlimited, default: number of core)

 \item \kbd{mpi}: number of MPI process to use (limited to the number allocated by \kbd{mpirun},
 default: use all allocated process).