kelvinKer0Derivative

Evaluates the derivative of the Kelvin function of the second kind, ker, of order zero.

Synopsis

kelvinKer0Derivative (x)

Required Arguments

float x (Input)
Argument for which the function value is desired.

Return Value

The derivative of the Kelvin function of the second kind, ker, of order zero evaluated at x.

Description

The function \(\text{ker}'_0(x)\) is defined to be

\[\frac{d}{dx} \mathrm{ker}_0(x)\]

The function kelvinKer0Derivative is based on the work of Burgoyne (1963). If \(x<0\), NaN (Not a Number) is returned. If \(x\geq 119\), zero is returned.

Example

In this example, \(\text{ker}'_0(0.6)\) is evaluated.

from __future__ import print_function
from numpy import *
from pyimsl.math.kelvinKer0Derivative import kelvinKer0Derivative

x = 0.6
ans = kelvinKer0Derivative(x)
print("ker0'(0.6) = %f" % (ans))

Output

ker0'(0.6) = -1.456539