rename lab 3

labs/debugging/line.cpp

@@ -0,0 +1,42 @@
+#include <iomanip>
+#include <cmath>
+#include "point.h"
+#include "line.h"
+
+
+// A helper function to calculate the slope of a Line.
+std::ostream& operator<< (std::ostream &ostr, const Line &l) {
+  ostr << "Road: "
+       << l.get_a() << " ----- " << l.get_b()
+       << "  gradient = "
+       << std::fixed << std::setprecision(1) << std::setw(4)
+       << gradient(l);
+  return ostr;
+}
+
+
+// A helper function to calculate the gradient of a Line.
+double gradient(const Line &ln) {
+  float slope = compute_slope(ln.get_a(),ln.get_b());
+  // convert the slope into a percentage gradient
+  float gradient = 100.0 * fabs(slope);
+  // take the absolute value
+  if (gradient < 0) {
+    gradient * -1;
+  }
+  return gradient;
+}
+
+
+// A helper function to compare the gradient of two Lines.
+// (That can be used to sort a collection of roads.)
+bool steeper_gradient(const Line &m, const Line &n) {
+  double gradient_m = gradient(m); 
+  double gradient_n = gradient(n); 
+  if (gradient_m > gradient_n)
+    return true;
+  if (gradient_n > gradient_m)
+    return false;
+}
+
+