ellipticIntegralRF¶
Evaluates Carlson’s elliptic integral of the first kind \(R_F(x,y,z)\).
Synopsis¶
ellipticIntegralRF (x, y, z)
Required Arguments¶
- float
x
(Input) - First variable of the incomplete elliptic integral. It must be nonnegative.
- float
y
(Input) - Second variable of the incomplete elliptic integral. It must be nonnegative.
- float
z
(Input) - Third variable of the incomplete elliptic integral. It must be nonnegative.
Return Value¶
The complete elliptic integral \(R_F(x,y,z)\)
Description¶
Carlson’s elliptic integral of the first kind is defined to be
\[R_F(x,y,z) = \tfrac{1}{2} \int_0^{\infty}
\frac{dt}{[(t+x)(t+y)(t+z)]^{1/2}}\]
The arguments must be nonnegative and less than or equal to b/5. In
addition, x + y, x + z, and y + z must be greater than or equal
to 5s. Should any of these conditions fail, ellipticIntegralRF
is
set to b. Here, b = machine(2) is the largest and s = machine(1) is
the smallest representable number. For more information, see the description
for machine.
The function ellipticIntegralRF
is based on the code by Carlson and
Notis (1981) and the work of Carlson (1979).