NAG Library Routine Document
G01QTF returns the value of the second moment of the Landau density function, via the routine name.
|REAL (KIND=nag_wp) G01QTF
G01QTF evaluates an approximation to the second moment
of the Landau density function given by
is described in G01MTF
, using piecewise approximation by rational functions. Further details can be found in Kölbig and Schorr (1984)
To obtain the value of
can be used.
Kölbig K S and Schorr B (1984) A program package for the Landau distribution Comp. Phys. Comm. 31 97–111
- 1: X – REAL (KIND=nag_wp)Input
On entry: the argument of the function.
6 Error Indicators and Warnings
There are no failure exits from this routine.
At least significant digits are usually correct, but occasionally only . Such accuracy is normally considered to be adequate for applications in experimental physics.
This example evaluates at , and prints the results.
9.1 Program Text
Program Text (g01qtfe.f90)
9.2 Program Data
Program Data (g01qtfe.d)
9.3 Program Results
Program Results (g01qtfe.r)