FOODIEFortran Object-Oriented Differential-equations Integration Environment

What FOODIE solves ​

FOODIE integrates in time the initial value problem

where $U_t=\frac{dU}{dt}$, $U$ is the vector of state variables, function of the time-like independent variable $t$, and $R$ is the (vectorial) residual function, possibly nonlinear in $U$. FOODIE is tailored to the systems arising from the semi-discretization of PDEs (the method of lines), but it is not limited to them.

A first integration ​

A concrete integrand, here the linear equation $U_t=aU+b$ of the tests suite, is integrated by any scheme through the factory:

use foodie, only : foodie_integrator_factory, integrator_object, integrator_multistage_object
...
class(integrator_object), allocatable :: integrator

call foodie_integrator_factory(scheme='runge_kutta_ssp_stages_3_order_3', integrator=integrator, U=integrand)
select type(integrator)
class is(integrator_multistage_object)
   do step=1, 100
      call integrator%integrate(U=integrand, Dt=0.01_R_P, t=time)
      time = time + 0.01_R_P
   enddo
endselect

The quick start builds the integrand and the loop step by step; the catalogue lists every scheme with its order and its references.

Authors ​

• Stefano Zaghi — @szaghi

Contributions are welcome — see the Contributing page.

Copyrights ​

This project is distributed under a multi-licensing system:

• FOSS projects: GPL v3
• Closed source / commercial: BSD 2-Clause, BSD 3-Clause, or MIT

Anyone interested in using, developing, or contributing to this project is welcome — pick the license that best fits your needs.