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fortran90
11-24-2013, 02:26 PM
tol in differential equation solvers is said to control the local error so that the global error is proportional to tol. I have searched but the documentations do not show how this is implemented. I am used to absolute and relative errors which are checked on each step size taken by the solver. How is tol related to absolute and relative errors used in each step size? The default tol = 1e-3 is that the same as relative error = 1e-3 or absolute error = 1e-3 on each step size? Can absolute and relative errors be controlled in the various routines through param?
Thank you