ASTR 5540 Math Meth Fall 2008. Problem Set 4. Due Mon Sep 22
1. Error-controlled numerical integrator
(a) Code
Write a routine that calls the integrator that you wrote in Problem Set 2, that carries out
automatic stepsize control to specified relative and absolute error. As before, you are free
to choose the algorithm and language of your choice, the defaults being the c language, and
the 4th-order Runge-Kutta algorithm.
You are welcome to use the template routines on the class website at http://casa.colorado.
edu/∼ajsh/astr5540 08/prob.html. Since I want you to focus your energies on the routine
that does automatic stepsize control, the template routines include a complete, debugged
test driver routine test rk4e.c.
(b) Test
Test your code by integrating the equations for the evolution of hydrogen in a fast shock
from Problem Set 3.
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