Files
C-Plus-Plus/numerical_methods/babylonian_method.cpp
Ameya Chawla 2bd853e8fd feat : Implemented Babylonian Method
Babylonian method is used to calculate  square roots .
2021-11-04 14:55:32 +05:30

99 lines
2.9 KiB
C++

/**
* @file
* @brief [A babylonian method
* (BM)](https://en.wikipedia.org/wiki/Methods_of_computing_square_roots#Babylonian_method)
* is an algorithm that computes the square root.
* @details
* This algorithm has an application in use case scenario where a user wants find accurate square roots of large numbers
* @author [Ameya Chawla](https://github.com/ameyachawlaggsipu)
*/
#include <iostream> /// for IO operations
#include <cassert> /// for assert
/**
* @namespace numerical_methods
* @brief Numerical algorithms/methods
*/
namespace numerical_methods{
/**
* @brief Babylonian methods is an iterative function which returns
* square root of radicand
* @param radicand is the radicand
* @returns x1 the square root of radicand
*/
double babylonian_method(double radicand){
int i=1; /// To find initial root or rough approximation
while(i*i<=radicand){
i++;
}
i--; /// Real Initial value will be i-1 as loop stops on +1 value
double x0=i; ///Storing previous value for comparison
double x1=(radicand/x0+x0)/2; /// Storing calculated value for comparison
double temp; /// Temp variable to x0 and x1
while(std::max(x0,x1)-std::min(x0,x1)<0.0001)
{
temp=(radicand/x1+x1)/2; /// Newly calculated root
x0=x1;
x1=temp;
}
return x1; ///Returning final root
}
} // namespace numerical_methods
/**
* @brief Self-test implementations
* @details
* Declaring two test cases and checking for the error
* in predicted and true value is less than 0.0001.
* @returns void
*/
static void test() {
/* descriptions of the following test */
auto testcase1 = 125348; /// Testcase 1
auto testcase2 = 752080; /// Testcase 2
auto real_output1 = 354.045194855; /// Real Output 1
auto real_output2 = 867.225460881; /// Real Output 2
auto test_result1 = numerical_methods::babylonian_method(testcase1);
/// Test result for testcase 1
auto test_result2 = numerical_methods::babylonian_method(testcase2);
/// Test result for testcase 2
assert(std::max(test_result1,real_output1)-std::min(test_result1,real_output1)<0.0001);
/// Testing for test Case 1
assert(std::max(test_result2,real_output2)-std::min(test_result2,real_output2)<0.0001);
/// Testing for test Case 2
std::cout << "All tests have successfully passed!\n";
}
/**
* @brief Main function
* @param argc commandline argument count (ignored)
* @param argv commandline array of arguments (ignored)
* calls automated test function to test the working of fast fourier transform.
* @returns 0 on exit
*/
int main(int argc, char const *argv[]) {
test(); // run self-test implementations
// with 2 defined test cases
return 0;
}