**compose** - a n-ary function with n fields

Compose a n-ary function f with n fields.

geo omega ("circle");
space Xh (omega, "P1");
field uh (Xh, 1.0);
field vh = interpolate (compose(f,uh));

The

**compose** operator could be used in all non-linear expressions involved
in either the

**interpolate** or the

**integrate** functions (see
interpolate(4) and integrate(4)). The

**f** function could be either a
usual function or a functor.

The

**compose** function supports also the characteristic algorithm (see
characteristic(2)) used for convection.

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

The n-arity bases on the variadic template feature of the 2011 c++
normalisation. When this feature is not available, only unary and binary
functions are supported.

interpolate(4), integrate(4), characteristic(2)