peak Subroutine

public subroutine peak(n, fx, xm, fm, dx)

Scan periodogram for a peak and return its properties
Method:
For f=log(fx) fits a parabola 0.5(d2*x**2+d1*x)+f(2) where d2=f(1)+f(3)-2f(2), d1=f(3)-f(1) finds dxl & dxp such, that the linear and quadratic terms drop by 0.7 in log, i.e. by a factor of 2 (dx=HWHI).
(C) Alex Schwarzenberg-Czerny, 1999-2005 alex@camk.edu.pl

Arguments

Type IntentOptional AttributesName
integer, intent(in) :: n

periodogram length

real(kind=SP), intent(in) :: fx(n)

periodogram values

real(kind=TIME), intent(out) :: xm

peak location (in index units, 1<xm<n)

real(kind=SP), intent(out) :: fm

peak value;

real(kind=SP), intent(out) :: dx

peak halfwidth HWHI,dx<0 no valid peak


Contents

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