bessel_k0_real_vectorreturns an array of values of the modified Bessel function .
For full information please refer to the NAG Library document for s18aq
- xfloat, array-like, shape
The argument of the function, for .
- ffloat, ndarray, shape
, the function values.
- ivalidint, ndarray, shape
contains the error code for , for .
, is undefined. contains .
- (errno )
On entry, .
- (errno )
On entry, at least one value of was invalid.
Check for more information.
bessel_k0_real_vectorevaluates an approximation to the modified Bessel function of the second kind for an array of arguments , for .
Note: is undefined for and the function will fail for such arguments.
The function is based on five Chebyshev expansions:
For near zero, , where denotes Euler’s constant. This approximation is used when is sufficiently small for the result to be correct to machine precision.
For large , where there is a danger of underflow due to the smallness of , the result is set exactly to zero.
NIST Digital Library of Mathematical Functions