std::map<unsigned int,double> &boundary_values);
/**
- * Compute the error of the finite element solution.
- * Integrate the difference between
- * a finite element function and
- * a reference function, which
- * is given as a continuous function
- * object.
+ * Compute the error of the
+ * finite element solution.
+ * Integrate the difference
+ * between a finite element
+ * function and a reference
+ * function, which is given as a
+ * continuous function object.
*
* The value of @p exponent is
* used for computing $L^p$-norms
* and $W^{1,p}$-norms.
*
- * The additional argument
- * @p weight allows to evaluate
+ * The additional argument @p
+ * weight allows to evaluate
* weighted norms. The weight
- * function may be
- * one-dimensional, establishing
- * a weight in the domain. It
- * also may have as many
+ * function may be scalar,
+ * establishing a weight in the
+ * domain for all components
+ * equally. This may be used, for
+ * instance, to only integrates
+ * over parts of the domain.
+ *
+ * The weight function may also
+ * be vector-valued, with as many
* components as the finite
* element function: Then,
* different components get
- * different weights. This can
- * be applied for instant with
- * the characteristic function of
- * a subset of the domain or a
- * weight function selecting only
- * some components of the
- * solution. The weight function
- * is expected to be positive,
- * but negative values are not
+ * different weights. A typical
+ * application is when the error
+ * with respect to only one or a
+ * subset of the solution
+ * variables is to be computed,
+ * in which the other components
+ * would have weight values equal
+ * to zero. The
+ * ComponentSelectFunction class
+ * is particularly useful for
+ * this purpose.
+ *
+ * The weight function is
+ * expected to be positive, but
+ * negative values are not
* filtered. By default, no
* weighting function is given,
* i.e. weight=1 in the whole
- * domain.
+ * domain for all vector
+ * components uniformly.
*
* It is assumed that the number
* of components of the function