Imported Upstream version 3.16.0upstream/3.16.0

1 files changed, 36 insertions, 0 deletions

diff --git a/Help/guide/tutorial/Step4/tutorial.cxx b/Help/guide/tutorial/Step4/tutorial.cxx
new file mode 100644
index 000000000..b3c6a4f43
--- /dev/null
+++ b/Help/guide/tutorial/Step4/tutorial.cxx
@@ -0,0 +1,36 @@
+// A simple program that computes the square root of a number
+#include <cmath>
+#include <iostream>
+#include <string>
+
+#include "TutorialConfig.h"
+
+// should we include the MathFunctions header?
+#ifdef USE_MYMATH
+#  include "MathFunctions.h"
+#endif
+
+int main(int argc, char* argv[])
+{
+  if (argc < 2) {
+    // report version
+    std::cout << argv[0] << " Version " << Tutorial_VERSION_MAJOR << "."
+              << Tutorial_VERSION_MINOR << std::endl;
+    std::cout << "Usage: " << argv[0] << " number" << std::endl;
+    return 1;
+  }
+
+  // convert input to double
+  const double inputValue = std::stod(argv[1]);
+
+  // which square root function should we use?
+#ifdef USE_MYMATH
+  const double outputValue = mysqrt(inputValue);
+#else
+  const double outputValue = sqrt(inputValue);
+#endif
+
+  std::cout << "The square root of " << inputValue << " is " << outputValue
+            << std::endl;
+  return 0;
+}