Syntax

  #include <math.h>  
   
  double j0  (  
     double   x);
  

  double j1  (  
     double   x);
  

  double jn  (  
     int      n,   
     double   x);
  

  double y0  (  
     double   x);
  

  double y1  (  
     double   x);
  

  double yn  (  
     int      n,   
     double   x);
  

Return Values

The result of the desired Bessel function of the argument x is returned. For y0, y1, or yn, if x is negative the routine sets errno to EDOM, prints a DOMAIN error message to stderr, and returns -HUGE_VAL.

Remarks

Functions j0, j1, and jn return Bessel functions of the first kind.

Functions y0, y1, and yn return Bessel functions of the second kind. The argument x must be positive.

See Also

matherr

Example

  #include <math.h>  
  #include <stdio.h> 
    
  main ()  
  {  
      double x, y, z;  
       x = j0( 2.4 );  
       y = y1( 1.58 );  
       z = jn( 3, 2.4 );  
       printf( "j0(2.4) = %f, y1(1.58) = %f\n", x, y );  
       printf( "jn(3,2.4) = %f\n", z );  
  }