init

Step3/MathFunctions/CMakeLists.txt

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+add_library(MathFunctions mysqrt.cxx)
+
+# TODO 1: State that anybody linking to MathFunctions needs to include the
+# current source directory, while MathFunctions itself doesn't.
+# Hint: Use target_include_directories with the INTERFACE keyword

Step3/MathFunctions/MathFunctions.h

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+double mysqrt(double x);

Step3/MathFunctions/mysqrt.cxx

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+#include <iostream>
+
+#include "MathFunctions.h"
+
+// a hack square root calculation using simple operations
+double mysqrt(double x)
+{
+  if (x <= 0) {
+    return 0;
+  }
+
+  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;
+}