RALDF
This function evaluates the Rayleigh cumulative distribution function.
Function Return Value
RALDF — Function value, the probability that a Rayleigh random variable takes a value less than or equal to X. (Output)
Required Arguments
X — Argument for which the Rayleigh cumulative distribution function is to be evaluated. (Input)
ALPHA — Scale parameter of the Rayleigh cumulative distribution function. (Input)
FORTRAN 90 Interface
Generic: RALDF (X, ALPHA)
Specific: The specific interface names are S_RALDF and D_RALDF.
FORTRAN 77 Interface
Single: RALDF (X, ALPHA)
Double: The double precision name is DRALDF.
Description
The function RALDF evaluates the Rayleigh cumulative probability distribution function, which is a special case of the Weibull cumulative probability distribution function, where the shape parameter GAMMA is 2.0
RALDF evaluates the Rayleigh cumulative probability distribution function using the relationship
RALDF(X, ALPHA) = WBLDF(X, SQRT(2.0)*ALPHA, 2.0).
Example
In this example, we evaluate the Rayleigh cumulative distribution function at X = 0.25, ALPHA = 0.5.
USE UMACH_INT
USE RALDF_INT
IMPLICIT NONE
INTEGER NOUT
REAL X, ALPHA, PR
CALL UMACH(2, NOUT)
X = 0.25
ALPHA = 0.5
PR = RALDF(X, ALPHA)
WRITE (NOUT, 99999) X, ALPHA, PR
99999 FORMAT (' RALDF(', F4.2, ', ', F4.2, ') = ', F6.4)
END
Output
RALDF(0.25, 0.50) = 0.1175
