Add dynamically allocated versions of matrix and vector

[libs/math.git] / source / linal / matrix.h

diff --git a/source/linal/matrix.h b/source/linal/matrix.h
index 929c48247e517aa47d837df1438c94465e25064a..a57ce08d68b78f6d2f49cd3bffbc16fbc223847f 100644 (file)
--- a/source/linal/matrix.h
+++ b/source/linal/matrix.h
@@ -13,6 +13,9 @@ A general mathematical matrix with M rows and N columns.
 template<typename T, unsigned M, unsigned N>
 class Matrix
 {
+public:
+       typedef T ElementType;
+
 private:
        T data[M*N];
 
@@ -25,11 +28,17 @@ public:
        static Matrix from_columns(const Vector<T, M> *);
        static Matrix from_rows(const Vector<T, N> *);
 
+       unsigned rows() const { return M; }
+       unsigned columns() const { return N; }
+
        T &element(unsigned i, unsigned j) { return data[i+M*j]; }
        const T &element(unsigned i, unsigned j) const { return data[i+M*j]; }
        T &operator()(unsigned i, unsigned j) { return element(i, j); }
        const T &operator()(unsigned i, unsigned j) const { return element(i, j); }
 
+       template<unsigned P, unsigned Q>
+       Matrix<T, P, Q> select(const Vector<unsigned, P> &, const Vector<unsigned, Q> &) const;
+
        template<unsigned P, unsigned Q>
        Matrix<T, P, Q> block(unsigned, unsigned) const;
 
@@ -84,6 +93,17 @@ inline Matrix<T, M, N> Matrix<T, M, N>::from_rows(const Vector<T, N> *v)
        return m;
 }
 
+template<typename T, unsigned M, unsigned N>
+template<unsigned P, unsigned Q>
+inline Matrix<T, P, Q> Matrix<T, M, N>::select(const Vector<unsigned, P> &rows, const Vector<unsigned, Q> &cols) const
+{
+       Matrix<T, P, Q> r;
+       for(unsigned j=0; j<P; ++j)
+               for(unsigned i=0; i<Q; ++i)
+                       r(j, i) = element(rows[j], cols[i]);
+       return r;
+}
+
 template<typename T, unsigned M, unsigned N>
 template<unsigned P, unsigned Q>
 inline Matrix<T, P, Q> Matrix<T, M, N>::block(unsigned y, unsigned x) const