generate_canonical Function template in C++

Last Updated : 11 Sep, 2018

This template in C++ is used to convert the value generated by g into a floating point value in the range [0, 1) preserving the uniformity properties of sequences generated with g. To generate enough entropy generate_canonical() will call g() exactly ‘k’ times where,

$k = max(1, \lceil \frac{b}{log_2 R} \rceil)$

Syntax:

template ( class RealType, size_t bits, class URNG )
RealType generate_canonical (URNG& g);

Template parameters: This template accepts three parameters as mentioned above and described below:

RealType: The function returns a value of floating point type.
bits: Maximum number of bits in the mantissa.
URNG: A uniform random number generator class.

Parameters: The generate_canonical() function accepts single parameter g which is used as uniform random number generator object. It is used to acquire entropy.

Return value: This function returns a floating point value in range [0, 1).

Below programs illustrate the above C++ template
Program:

// C++ program to illustrate generate_canonical() 
// function. 
#include <bits/stdc++.h> 
using namespace std; 
  
int main() 
{ 
    // Obtain a root from the system clock: 
    unsigned root = chrono::system_clock::now().time_since_epoch().count(); 
  
    // Random number engine class 
    // that generates pseudo-random numbers 
    default_random_engine generator(root); 
    double can_val = generate_canonical<double,  
                              numeric_limits<double>::digits>(generator); 
  
    // Print the random canonical value 
    // It will display different value everytime 
    cout << "Random canonical value: " << can_val; 
  
    return 0; 
} 

Output:

Random canonical value: 0.0281975

Reference: http://www.cplusplus.com/reference/random/generate_canonical/

Attention reader! Don’t stop learning now. Get hold of all the important C++ Foundation and STL concepts with the C++ Foundation and STL courses at a student-friendly price and become industry ready.

My Personal Notes

Related Articles