1 files changed, 37 insertions, 0 deletions
diff --git a/Help/guide/tutorial/Step7/MathFunctions/mysqrt.cxx b/Help/guide/tutorial/Step7/MathFunctions/mysqrt.cxx
new file mode 100644
index 0000000..9963cff
--- /dev/null
+++ b/Help/guide/tutorial/Step7/MathFunctions/mysqrt.cxx
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+#include "mysqrt.h"
+
+#include <iostream>
+
+namespace mathfunctions {
+namespace detail {
+// a hack square root calculation using simple operations
+double mysqrt(double x)
+{
+  if (x <= 0) {
+    return 0;
+  }
+
+  // TODO 5: If both HAVE_LOG and HAVE_EXP are defined,  use the following:
+  //// double result = std::exp(std::log(x) * 0.5);
+  //// std::cout << "Computing sqrt of " << x << " to be " << result
+  ////        << " using log and exp" << std::endl;
+  // else, use the existing logic.
+
+  // Hint: Don't forget the #endif before returning the result!
+
+  double result = x;
+
+  // do ten iterations
+  for (int i = 0; i < 10; ++i) {
+    if (result <= 0) {
+      result = 0.1;
+    }
+    double delta = x - (result * result);
+    result = result + 0.5 * delta / result;
+    std::cout << "Computing sqrt of " << x << " to be " << result << std::endl;
+  }
+
+  return result;
+}
+}
+}