Added .is_polynomial() method.

[ginac.git] / ginac / matrix.cpp

diff --git a/ginac/matrix.cpp b/ginac/matrix.cpp
index 623537febbb965f5ac1324e77f85e07d59a00768..f62e2d409244d8a50d44890b8eae74f8ac5e4eb1 100644 (file)
--- a/ginac/matrix.cpp
+++ b/ginac/matrix.cpp
@@ -3,7 +3,7 @@
  *  Implementation of symbolic matrices */
 
 /*
- *  GiNaC Copyright (C) 1999-2005 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2006 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -53,7 +53,7 @@ GINAC_IMPLEMENT_REGISTERED_CLASS_OPT(matrix, basic,
 //////////
 
 /** Default ctor.  Initializes to 1 x 1-dimensional zero-matrix. */
-matrix::matrix() : inherited(TINFO_matrix), row(1), col(1), m(1, _ex0)
+matrix::matrix() : inherited(&matrix::tinfo_static), row(1), col(1), m(1, _ex0)
 {
        setflag(status_flags::not_shareable);
 }
@@ -69,7 +69,7 @@ matrix::matrix() : inherited(TINFO_matrix), row(1), col(1), m(1, _ex0)
  *  @param r number of rows
  *  @param c number of cols */
 matrix::matrix(unsigned r, unsigned c)
-  : inherited(TINFO_matrix), row(r), col(c), m(r*c, _ex0)
+  : inherited(&matrix::tinfo_static), row(r), col(c), m(r*c, _ex0)
 {
        setflag(status_flags::not_shareable);
 }
@@ -78,7 +78,7 @@ matrix::matrix(unsigned r, unsigned c)
 
 /** Ctor from representation, for internal use only. */
 matrix::matrix(unsigned r, unsigned c, const exvector & m2)
-  : inherited(TINFO_matrix), row(r), col(c), m(m2)
+  : inherited(&matrix::tinfo_static), row(r), col(c), m(m2)
 {
        setflag(status_flags::not_shareable);
 }
@@ -88,7 +88,7 @@ matrix::matrix(unsigned r, unsigned c, const exvector & m2)
  *  If the list has more elements than the matrix, the excessive elements are
  *  thrown away. */
 matrix::matrix(unsigned r, unsigned c, const lst & l)
-  : inherited(TINFO_matrix), row(r), col(c), m(r*c, _ex0)
+  : inherited(&matrix::tinfo_static), row(r), col(c), m(r*c, _ex0)
 {
        setflag(status_flags::not_shareable);
 
@@ -580,10 +580,11 @@ matrix matrix::mul(const matrix & other) const
        
        for (unsigned r1=0; r1<this->rows(); ++r1) {
                for (unsigned c=0; c<this->cols(); ++c) {
+                       // Quick test: can we shortcut?
                        if (m[r1*col+c].is_zero())
                                continue;
                        for (unsigned r2=0; r2<other.cols(); ++r2)
-                               prod[r1*other.col+r2] += (m[r1*col+c] * other.m[c*other.col+r2]).expand();
+                               prod[r1*other.col+r2] += (m[r1*col+c] * other.m[c*other.col+r2]);
                }
        }
        return matrix(row, other.col, prod);
@@ -1598,4 +1599,52 @@ ex symbolic_matrix(unsigned r, unsigned c, const std::string & base_name, const
        return M;
 }
 
+ex reduced_matrix(const matrix& m, unsigned r, unsigned c)
+{
+       if (r+1>m.rows() || c+1>m.cols() || m.cols()<2 || m.rows()<2)
+               throw std::runtime_error("minor_matrix(): index out of bounds");
+
+       const unsigned rows = m.rows()-1;
+       const unsigned cols = m.cols()-1;
+       matrix &M = *new matrix(rows, cols);
+       M.setflag(status_flags::dynallocated | status_flags::evaluated);
+
+       unsigned ro = 0;
+       unsigned ro2 = 0;
+       while (ro2<rows) {
+               if (ro==r)
+                       ++ro;
+               unsigned co = 0;
+               unsigned co2 = 0;
+               while (co2<cols) {
+                       if (co==c)
+                               ++co;
+                       M(ro2,co2) = m(ro, co);
+                       ++co;
+                       ++co2;
+               }
+               ++ro;
+               ++ro2;
+       }
+
+       return M;
+}
+
+ex sub_matrix(const matrix&m, unsigned r, unsigned nr, unsigned c, unsigned nc)
+{
+       if (r+nr>m.rows() || c+nc>m.cols())
+               throw std::runtime_error("sub_matrix(): index out of bounds");
+
+       matrix &M = *new matrix(nr, nc);
+       M.setflag(status_flags::dynallocated | status_flags::evaluated);
+
+       for (unsigned ro=0; ro<nr; ++ro) {
+               for (unsigned co=0; co<nc; ++co) {
+                       M(ro,co) = m(ro+r,co+c);
+               }
+       }
+
+       return M;
+}
+
 } // namespace GiNaC