vmf Month Mode Frequency Tables
vmx Month MFT for Rotation Corrected L-Nu diagram
vnx Incoherent-average Month MFT for Rotation Corrected
L-Nu diagram
vnf Incoherent-average Month MFT for Rotation Corrected
L-Nu diagram
vyf Year Mode Frequency Tables
vyx Year MFT for Rotatin Corrected L-Nu diagram
The GRASP task GRTOOLS.PEAKFIND is used on the individual power spectra resulting in STSDAS binary tables.
The current PEAKFIND defaults (of interest) are:
cl> lpar peakfind
input = Input Power Spectrum Image
output = Output Fit image
table = Output Mode-Frequency Table
(lm_start = INDEF) Starting L or M value to be fit
(lm_end = INDEF) Ending L or M value to be fit
(n_start = INDEF) Starting N-value to be fit
(n_end = INDEF) Ending N-value to be fit
(window = "") Window Function Image
(fit_backgrou = yes) Fit the background?
(bkg_thresh = 3.) Sigma-threshold for accepting amplitude guess?
(bkg_smooth = 17) Background smoothing kernel width (must be odd)
(bkg0 = 0.) Background intercept
(bkg1 = 0.) Background slope
(bkg_spectrum = "") Background Image Name if not fitting
(restart = 1) Number of Amoeba restarts
(nleaks = 0) Number of leaks to fit
(model = "lorentz") Model profile (lorentz|osaki)
(minimize = "bfgs") Algorithm (amoeba1|amoeba2|dfp|bfgs|pikaia)
(nu_guess_tab = "grasplib$nu_table.dat") Initial guess frequency table.
(legpars = "") Legendre a-coefficient definition parameters
(pikaia_gen = 500) Number of PIKAIA Generations
(pikaia_pop = 100) Number of PIKAIA Populations (even)
(random_pertu = no) Do random perturbations about the Fit?
(n_realizatio = 50) Number of random realizations to be done?
(sigma_random = 3.) Perturbation size.?
(freq_grid = no) Do a frequency grid about the Fit?
(n_gridpoints = 30) Number of grid points
(grid_spacing = 0.01) Frequency grid spacing.
The raw output of PEAKFIND is processed through the task PKANALYSE which selects out the primary targets from the tables, and then performs a series of tests to determine whether or not the fit is good. The final v[mnxy]f tables are ASCII text files. The header of each file contains a description of columns of that file, as well as some statistical information regarding the data product set as a whole. For example:
MRVNF960307 -- Average of Months 4-14
COLUMN COLUMN NAME UNITS DESCRIPTION
==========================================================================
1 n Radial order
2 l Degree
3 m Azimuthal order
4 nuguess microHz Initial guess frequency
5 fwguess microHz Initial guess FWHM
6 nu microHz Fit Frequency
7 dnu microHz Frequency error
8 fwhm microHz Fit FWHM
9 dpfwhm microHz Positive FWHM error bar
10 dmfwhm microHz Negative FWHM error bar
11 psamp (m/s)**2/Hz Fit Power spectrum amplitude
12 dppsamp (m/s)**2/Hz Positive PSAMP error bar
13 dmpsamp (m/s)**2/Hz Negative PSAMP error bar
14 bkg0 (m/s)**2/Hz Fit background power at nu
15 dbkg0 (m/s)**2/Hz Background power error
16 bkg1 (m/s)**2/Hz Fit background slope
17 dbkg1 (m/s)**2/Hz Background slope error
18 merit Merit function value
19 niter Number of iterations to solution
20 bad Good fit == 0, Bad Fit 0
21 ierr BFGS error code
NOTE: "bad" is a 8 digit integer describing the rejection criteria:
A fit is considered bad if:
BFGS error code 100 10000000
The following is a convergence criteria:
(abs(df) 0.1) || (diff 10) || (diff2 2) 01000000
(|nu - nuguess| fwguess) 00100000
merit 2.0 00010000
Power(mode)/Power(background) <= 1. 00001000
dnu 5. 00000100
dnu fwguess/2. 00000010
(fwhm/fwguess 5.) || (fwguess/fwhm 5.) 00000001
Total Number of primary modes fit: 334291
Number of primary modes considered good: 313607
Number of primary modes considered bad: 20684
Bad IERR: 2888
Bad Convergence: 2324
Bad Frequency: 129
Bad Merit: 224
Bad Power: 1517
Bad dnu1: 3396
Bad dnu2: 1467
Bad Width: 15097
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