Eigen  3.4.90 (git rev 67eeba6e720c5745abc77ae6c92ce0a44aa7b7ae)
Eigen::symbolic Namespace Reference


class  BaseExpr
class  SymbolExpr
class  SymbolValue

Detailed Description

This namespace defines a set of classes and functions to build and evaluate symbolic expressions of scalar type Index. Here is a simple example:

// First step, defines symbols:
struct x_tag {}; static const symbolic::SymbolExpr<x_tag> x;
struct y_tag {}; static const symbolic::SymbolExpr<y_tag> y;
struct z_tag {}; static const symbolic::SymbolExpr<z_tag> z;
// Defines an expression:
auto expr = (x+3)/y+z;
// And evaluate it: (c++14)
std::cout << expr.eval(x=6,y=3,z=-13) << "\n";

It is currently only used internally to define and manipulate the Eigen::placeholders::last and Eigen::placeholders::lastp1 symbols in Eigen::seq and Eigen::seqN.