NAME

       compose - n-ary function application in expressions (rheolef-7.2)

SYNOPSIS

       template <class Function, class... Expressions>
       Expression compose (const Function& f, const Expressions&... exprs);

DESCRIPTION

       Compose a n-ary function f with n fields in interpolate(3) and integrate(3) nonlinear
       expressions.

EXAMPLE

       The compose operator is used for applying a user-provided function to a field:

           Float f (Float u) { return 1/u + sqrt(u); }
           ...
           field vh = interpolate (Xh, compose(f, uh));

        When two arguments are involved:

           Float g (Float u, Float v) { return v/u + sqrt(u*v); }
           ...
           field wh = interpolate (Xh, compose(g, uh, vh));

        The compose operator supports general n-ary functions and class-functions.

CHARACTERISTIC

       The compose function supports also the method of characteristic(2) used e.g. for
       convection-diffusion problems:

           characteristic X (-delta_t*uh);
           test v (Xh);
           field lh = integrate (compose(uh,X)*v);

IMPLEMENTATION

       This documentation has been generated from file main/lib/compose.h

AUTHOR

       Pierre  Saramito  <Pierre.Saramito@imag.fr>

COPYRIGHT

       Copyright   (C)  2000-2018  Pierre  Saramito  <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL
       version 3 or later  <http://gnu.org/licenses/gpl.html>.  This  is  free  software:  you
       are free to change and redistribute it.  There is NO WARRANTY, to the extent permitted by
       law.