added example for namespace bracing

[ginac.git] / ginac / matrix.h

diff --git a/ginac/matrix.h b/ginac/matrix.h
index f5cd5de83dde6d208d3afabbf511c9c840e44650..fc6a80bf4e6b3127eb701809792d948fdb694525 100644 (file)
--- a/ginac/matrix.h
+++ b/ginac/matrix.h
@@ -30,6 +30,65 @@
 
 namespace GiNaC {
 
+
+/** Helper template to allow initialization of matrices via an overloaded
+ *  comma operator (idea stolen from Blitz++). */
+template <typename T, typename It>
+class matrix_init {
+public:
+       matrix_init(It i) : iter(i) {}
+
+       matrix_init<T, It> operator,(const T & x)
+       {
+               *iter = x;
+               return matrix_init<T, It>(++iter);
+       }
+
+       // The following specializations produce much tighter code than the
+       // general case above
+
+       matrix_init<T, It> operator,(int x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+       matrix_init<T, It> operator,(unsigned int x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+       matrix_init<T, It> operator,(long x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+       matrix_init<T, It> operator,(unsigned long x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+       matrix_init<T, It> operator,(double x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+       matrix_init<T, It> operator,(const symbol & x)
+       {
+               *iter = T(x);
+               return matrix_init<T, It>(++iter);
+       }
+
+private:
+       matrix_init();
+       It iter;
+};
+
+
 /** Symbolic matrices. */
 class matrix : public basic
 {
@@ -40,6 +99,14 @@ public:
        matrix(unsigned r, unsigned c);
        matrix(unsigned r, unsigned c, const exvector & m2);
        matrix(unsigned r, unsigned c, const lst & l);
+
+       // First step of initialization of matrix with a comma-separated seqeuence
+       // of expressions. Subsequent steps are handled by matrix_init<>::operator,().
+       matrix_init<ex, exvector::iterator> operator=(const ex & x)
+       {
+               m[0] = x;
+               return matrix_init<ex, exvector::iterator>(++m.begin());
+       }
        
        // functions overriding virtual functions from base classes
 public:
@@ -76,7 +143,7 @@ public:
        matrix transpose() const;
        ex determinant(unsigned algo = determinant_algo::automatic) const;
        ex trace() const;
-       ex charpoly(const symbol & lambda) const;
+       ex charpoly(const ex & lambda) const;
        matrix inverse() const;
        matrix solve(const matrix & vars, const matrix & rhs,
                     unsigned algo = solve_algo::automatic) const;
@@ -87,7 +154,7 @@ protected:
        int fraction_free_elimination(const bool det = false);
        int pivot(unsigned ro, unsigned co, bool symbolic = true);
 
-       void print_elements(const print_context & c, const std::string & row_start, const std::string & row_end, const std::string & row_sep, const std::string & col_sep) const;
+       void print_elements(const print_context & c, const char *row_start, const char *row_end, const char *row_sep, const char *col_sep) const;
        void do_print(const print_context & c, unsigned level) const;
        void do_print_latex(const print_latex & c, unsigned level) const;
        void do_print_python_repr(const print_python_repr & c, unsigned level) const;
@@ -129,7 +196,7 @@ inline ex determinant(const matrix & m, unsigned options = determinant_algo::aut
 inline ex trace(const matrix & m)
 { return m.trace(); }
 
-inline ex charpoly(const matrix & m, const symbol & lambda)
+inline ex charpoly(const matrix & m, const ex & lambda)
 { return m.charpoly(lambda); }
 
 inline matrix inverse(const matrix & m)