CMake/Help/guide/tutorial/Step8/tutorial.cxx
Betsy McPhail 82332f81bb Tutorial: Improve Step 1
* Update minimum required version to 3.10
* Use VERSION argument to project command rather than separate variables
* Replace `endif(USE_MYMATH)` with  more modern `endif()`
* Simplify the call to 'configure_file()'
* Add comments to tutorial.cxx to use as anchors in documentation
* Remove CMakeLists and TutorialConfig.h.in files that users should
  create. Consequently, remove Step1 from CMake tests.
2019-08-19 11:48:58 -04:00

37 lines
904 B
C++

// 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;
}