Ex8 and minor improvements

sheet3/8/vdop.h

@@ -0,0 +1,58 @@
+#ifndef VDOP_FILE
+#define VDOP_FILE
+#include <vector>
+
+/** @brief  Element-wise vector divison x_k = y_k/z_k.
+ *
+ * @param[out] x  target vector
+ * @param[in]  y  source vector
+ * @param[in]  z  source vector
+ *
+ */
+void vddiv(std::vector<double> & x, std::vector<double> const& y,
+                                    std::vector<double> const& z);
+
+/** @brief  Element-wise daxpy operation x(k) = y(k) + alpha*z(k).
+ *
+ * @param[out] x  target vector
+ * @param[in]  y  source vector
+ * @param[in]  alpha  scalar
+ * @param[in]  z  source vector
+ *
+ */
+void vdaxpy(std::vector<double> & x, std::vector<double> const& y,
+                       double alpha, std::vector<double> const& z );
+
+
+/** @brief  Calculates the Euclidian inner product of two vectors.
+ *
+ * @param[in]  x vector
+ * @param[in]  y vector
+ * @return Euclidian inner product @f$\langle x,y \rangle@f$
+ *
+ */
+double dscapr(std::vector<double> const& x, std::vector<double> const& y);
+
+
+/**
+ * Print entries of a vector.
+ * @param[in] v	    vector values
+*/
+void DebugVector(std::vector<double> const &v);
+
+/** @brief  Compares an STL vector with POD vector.
+ *
+ * The accuracy criteria @f$ |x_k-y_k| < \varepsilon \left({1+0.5(|x_k|+|y_k|)}\right) @f$
+ * follows the book by
+ * <a href="https://www.springer.com/la/book/9783319446592">Stoyan/Baran</a>, p.8.
+ *
+ * @param[in]  x    STL vector
+ * @param[in]  n    length of POD vector
+ * @param[in]  y    POD vector
+ * @param[in]  eps  relative accuracy criteria (default := 0.0).
+ * @return true iff pairwise vector elements are relatively close to each other.
+ *
+ */
+bool CompareVectors(std::vector<double> const& x, int n, double const y[], double const eps=0.0);
+
+#endif