pkb and a2z format#
a2z DataFrames#
The syntax of the a2z files has been designed to specify some pieces of
information the procedure has to be aware of when dealing with individual mode
parameters extraction. A line corresponds to a parameter. The file contains
nine columns: order n, degree l, name of the parameter, extent,
value, uncertainty, fixed key, low bound and up bound of
the parameter.
If a parameter has to apply to every order or degrees, the value to specify in
the corresponding column is a. The possible parameters name are freq,
height, width, asym, angle, split. Parameters with name freq, height or
width cannot have n=a, parameters with name freq cannot have
l=a. The extent columns reminds the extent of application of a given
parameter: mode, even, odd, order or global. The even
and odd keywords can be used only with strategy=pair. The corresponding
parameter will be common to the two mode of a given (even or odd) pair. For an
input a2z file, the value column specify the value around where the sampler
will initialise the walkers that will sample the MCMC. The uncertainty
column is relevant only for output a2z files. The fixed key column values
must be set to 0 or 1 and are managed by the peakbagging function.
Parameters with fixed key 0 at a given step will be fitted while parameters
with 1-value will be read as frozen parameters. In input a2z files, the low
bound and up bound columns specify the limit values inside which the
posterior probability will be sampled. Obviously, the up bound must be
greater than the low bound, and the value term must lay inside the
defined interval.
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
n |
l |
name |
extent |
value |
value_error |
fixed |
low_bound |
up_bound |
l=4 and l=5 modes can be specified to avoid bias in the fitted frequencies
(see Jiménez-Reyes et al. 2008 for more details). It is important to keep in
mind that whether strategy is chosen (order or pair), those modes will
only be fitted if their guess frequency appears in the frequency window used
for the fit of modes of lower degrees. Note that for l=4 and l=5 modes, it
is possible to specify only the frequency in the a2z file, height and width
will be automatically computed considering the height and width of the closest
fitted l=0 or l=1 mode. In this case, splittings are fixed to 400 nHz and
no asymmetry is considered for those modes. All m-components of the mode have
the same amplitude ratio.
pkb arrays#
In pkb files, each line correspond to a given mode of order n and degree l. The file
contains 14 columns: order n, degree l, mode frequency, uncertainty over frequency,
mode height, uncertainty over height, mode width, uncertainty over width, stellar angle,
uncertainty over stellar angle, mode splitting, uncertainty over mode splitting, mode
asymmetry, uncertainty over mode asymmetry.
index |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
parameters |
n |
l |
\(\nu\) |
\(\sigma\) ν |
height |
\(\sigma\) height |
width |
\(\sigma\) width |
angle |
\(\sigma\) angle |
split |
\(\sigma\) split |
asym |
\(\sigma\) asym |
units |
. |
. |
µHz |
µHz |
power/µHz |
power/µHz |
µHz |
µHz |
degree |
degree |
µHz |
µHz |
. |
. |
Extended pkb arrays#
The format of the extended pkb array is close to the classical pkb array, except that, for each parameters, it contains two uncertainty value: \(\sigma\) +, corresponding to the difference between the 16th centiles and the median of the distribution, and \(\sigma\) -, corresponding to the difference between the median and the 84th centile of the distribution.
index |
0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
11 |
12 |
13 |
14 |
15 |
16 |
17 |
18 |
19 |
parameters |
n |
l |
\(\nu\) |
\(\sigma\) ν,- |
\(\sigma\) ν,+ |
height |
\(\sigma\) height,- |
\(\sigma\) height,+ |
width |
\(\sigma\) width,- |
\(\sigma\) width,+ |
angle |
\(\sigma\) angle,- |
\(\sigma\) angle,+ |
split |
\(\sigma\) split,- |
\(\sigma\) split,+ |
asym |
\(\sigma\) asym,- |
\(\sigma\) asym,+ |
units |
. |
. |
µHz |
µHz |
µHz |
power/µHz |
power/µHz |
power/µHz |
µHz |
µHz |
µHz |
degree |
degree |
degree |
µHz |
µHz |
µHz |
. |
. |
. |
Examples#
Here is an example of an a2z DataFrame :
19 1 freq mode 2198.735167 0.0 0.0 2191.577557 2205.892778
18 2 freq mode 2251.859534 0.0 0.0 2244.701923 2259.017145
19 0 freq mode 2256.762699 0.0 0.0 2249.605088 2263.920310
19 a height order 7.592848 0.0 0.0 3.796424 30.371392
19 a width order 0.949858 0.0 0.0 0.474929 1.899717
20 1 freq mode 2308.901246 0.0 0.0 2301.743635 2316.058857
19 2 freq mode 2362.025612 0.0 0.0 2354.868002 2369.183223
20 0 freq mode 2366.928778 0.0 0.0 2359.771167 2374.086388
20 a height order 8.582715 0.0 0.0 4.291358 34.330861
20 a width order 0.949858 0.0 0.0 0.474929 1.899717
21 1 freq mode 2419.239760 0.0 0.0 2412.082149 2426.397370
20 2 freq mode 2472.364126 0.0 0.0 2465.206516 2479.521737
21 0 freq mode 2477.267291 0.0 0.0 2470.109681 2484.424902
21 a height order 8.082355 0.0 0.0 4.041177 32.329420
21 a width order 0.949858 0.0 0.0 0.474929 1.899717
22 1 freq mode 2529.750709 0.0 0.0 2522.593098 2536.908319
21 2 freq mode 2582.875075 0.0 0.0 2575.717465 2590.032686
22 0 freq mode 2587.778241 0.0 0.0 2580.620630 2594.935851
22 a height order 6.335368 0.0 0.0 3.167684 25.341473
22 a width order 0.949858 0.0 0.0 0.474929 1.899717
23 1 freq mode 2640.434093 0.0 0.0 2633.276482 2647.591704
22 2 freq mode 2693.558460 0.0 0.0 2686.400849 2700.716070
23 0 freq mode 2698.461625 0.0 0.0 2691.304014 2705.619236
23 a height order 4.130032 0.0 0.0 2.065016 16.520129
23 a width order 0.949858 0.0 0.0 0.474929 1.899717
a a split global 0.000000 0.0 0.0 0.000000 1.000000
a a angle global 0.000000 0.0 0.0 0.000000 90.000000
a 1 amp_l global 1.500000 0.0 0.0 0.000000 0.000000
a 2 amp_l global 0.700000 0.0 0.0 0.000000 0.000000
a 0 amp_l global 1.000000 0.0 0.0 0.000000 0.000000
And here is the corresponding pkb array :
[[ 19. 1. 2198.735 0. 11.389 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 18. 2. 2251.86 0. 5.315 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 19. 0. 2256.763 0. 7.593 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 20. 1. 2308.901 0. 12.874 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 19. 2. 2362.026 0. 6.008 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 20. 0. 2366.929 0. 8.583 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 21. 1. 2419.24 0. 12.124 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 20. 2. 2472.364 0. 5.658 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 21. 0. 2477.267 0. 8.082 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 22. 1. 2529.751 0. 9.503 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 21. 2. 2582.875 0. 4.435 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 22. 0. 2587.778 0. 6.335 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 23. 1. 2640.434 0. 6.195 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 22. 2. 2693.558 0. 2.891 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]
[ 23. 0. 2698.462 0. 4.13 0. 0.95 0. 0. 0. 0. 0. 0. 0. ]]