From c014a8a6c1ed6a13891c7d05ea19ec0b6cc6128a Mon Sep 17 00:00:00 2001 From: Wolfgang Bangerth Date: Sun, 19 Apr 2015 17:16:35 -0500 Subject: [PATCH] Update documentation. This closes #542. --- include/deal.II/base/function_time.h | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) diff --git a/include/deal.II/base/function_time.h b/include/deal.II/base/function_time.h index 029d2312f0..6e3aa4c459 100644 --- a/include/deal.II/base/function_time.h +++ b/include/deal.II/base/function_time.h @@ -1,6 +1,6 @@ // --------------------------------------------------------------------- // -// Copyright (C) 1999 - 2014 by the deal.II authors +// Copyright (C) 1999 - 2015 by the deal.II authors // // This file is part of the deal.II library. // @@ -42,21 +42,27 @@ DEAL_II_NAMESPACE_OPEN * computations which need only be done once for every new time. For example, * if a time dependent function had a factor sin(t), then it may be a * reasonable choice to calculate this factor in a derived version of - * set_time, store it in a member variable and use that one rather - * than computing it every time operator(), value_list or - * one of the other functions is called. + * set_time(), store it in a member variable and use that one rather + * than computing it every time value(), value_list or + * one of the other functions of class Function is called. * - * By default, the advance_time function calls the set_time + * By default, the advance_time() function calls the set_time() * function with the new time, so it is sufficient in most cases to overload - * only set_time for computations as sketched out above. + * only set_time() for computations as sketched out above. * * The constructor of this class takes an initial value for the time variable, * which defaults to zero. Because a default value is given, none of the * derived classes needs to take an initial value for the time variable if not * needed. * - * Once again the warning: do not use the time variable for any other - * purpose than the intended one! This will inevitably lead to confusion. + * @tparam Number The data type in which time values are to be + * stored. This will, in almost all cases, simply be the default @p double, + * but there are cases where one may want to store the time in a different + * (and always scalar) type. An example would be an interval type that can + * store a value as well as its uncertainty. Another example + * would be a type that allows for Automatic Differentiation (see, for + * example, the Sacado type used in step-33) and thereby can generate analytic + * (temporal) derivatives of a function. * * * @ingroup functions -- 2.39.5