Recursive Chudnovsky Algorithm in Java -


i computer engineering student, , i've got project chudnovsky algorithm calculate pi, problem i've got decimal decimal(i mean if got length 3 it's going 3.14), have done code , 3.141592653589734 don't have idea how bit bit using recursive method.the code got far is

 //this class implements interface contains method calcularpi  public class chudnovsky_implements implements chudnovsky {   public  double calcularpi(int k)//this i'm trying bit bit i'm doing wrong. {            if(k==0)         return pi(k);     else {     double resultado= (pi(k))+(pi(k-1));     return resultado;      }  }  public double pi(int k)//here calculated number pi constant k user give(k supposedly number of digits) {     double numerador=(factorial(6*k)*((545140134*k)+13591409));     double denominador =(factorial(3*k)*math.pow(factorial(k), 3)*math.pow(-640320, (3*k)));     double pi=(numerador/denominador);     return pi; }   public double factorial(int n)// class calculate factorial of number  {     if (n==0)        return 1;     else        return n*(factorial(n-1)); }

if vague or don't quite understand english not main language sorry

this integer teacher gave

with recursion:

package q46166389;  public class chudnovsky {      public static void main( string[ ] args ) {         int k = 13;          final string outputformat = "%." + ( k - 1 ) + "f";          double result = new chudnovsky( ).calculateloop( k );          // format output desired number of decimals         system.out.println( "result = " + string.format( outputformat, result ) );         // or print it:         system.out.println( "result = " + result );          result = 1 / new chudnovsky( ).calculaterecursive( k );          system.out.println( "result = " + string.format( outputformat, result ) );         system.out.println( "result = " + result );     }      public double calculateloop( int k ) {         double result = 0;         ( int = 0; <= k; i++ ) {             result = result + docalc( );         }         return 1 / result;     }      public double calculaterecursive( int k ) {         if ( k == 0 ) { return docalc( k ); }          return docalc( k ) + calculaterecursive( k - 1 );     }      public double docalc( int k ) {         double numerator = math.pow( -1, k ) * factorial( 6 * k ) * ( 545140134 * k + 13591409 );         double denominator = factorial( 3 * k ) * math.pow( factorial( k ), 3 ) * math.pow( 640320, 3 * k + 3.0 / 2.0 );         return 12.0 * numerator / denominator;     }      public double factorial( int n ) {         if ( n == 0 ) {             return 1;         } else {             return n * factorial( n - 1 );         }     }  }

output:

result = 3.141592653590 result = 3.1415926535897936 result = 3.141592653590 result = 3.1415926535897936

please note answer works until k = 17 , have precision problems! if need more digits or more precision, need use bigdecimal.


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