j1(), j1f()

Compute a Bessel function of the first kind

Synopsis:

#include <math.h>

double j1( double x );

float j1f( float x );

Arguments:

x
The number that you want to compute the Bessel function for.

Library:

libm

Use the -l m option to qcc to link against this library.

Description:

These functions compute the Bessel function of the first kind for x.

To check for error situations, use feclearexcept() and fetestexcept():

Returns:

The result of the Bessel function of x.

If x argument is too large in magnitude, or the correct result would cause an underflow, 0 is returned, and a range error may occur. If x is NaN, NaN is returned.

Errors:

FE_UNDERFLOW
The value of x is too large in magnitude, or an underflow occurred.

Classification:

j1() is POSIX 1003.1 XSI; j1f() is Unix

Safety:  
Cancellation point No
Interrupt handler No
Signal handler No
Thread Yes