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