cc [ flag ... ] file ... -lm [ library ... ] #include <math.h>double j0(double x);
The j0(), j1() and jn() functions compute Bessel functions of x of the first kind of orders 0, 1 and n respectively.
Upon successful completion, j0(), j1() and jn() return the relevant Bessel value of x of the first kind.
If the x argument is too large in magnitude, 0 is returned and errno may be set to ERANGE.
If x is NaN, NaN is returned.
For exceptional cases, matherr(3M) tabulates the values to be returned as dictated by Standards other than XPG4.
An application wishing to check for error situations should set errno to 0 before calling j0(), j1() or jn(). If errno is non-zero on return, or the return value is NaN, an error has occurred.
See attributes(5) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|