Documentation.
Name:
calc_sharp_params.pro
Purpose:
This algorithm reproduces the 16 SHARP parameters included in the FITS headers metadata. These parameters, are described in Table 1 of Bobra et al. 2014. It also expands on the SHARP keywords to calculate other (spatial) distribution moments of the physical quntity: minimum and maximum values, mean, median, total, and other distribution moments such as the standard deviation (σ), skewness (ς), and kurtosis (κ). A good-pixels mask is used as well. In contrast to the original algorithm -- which uses a Green-function solver to calculate the surface potential field extrapolation -- the much faster FFT approach developed by Alissandrakis 1981 is used.
Calling sequence:
CALC_SHARP_PARAMS, images, ind, params_out [, act_kws]
Input parameters:
images = HARP cutout magnetogram corrected for limb presence.
ind = structure containing magnetogram's metada (resolution).
Optional input parameters:
act_kws = Optional keywords. Setup in the configuration files.
Output parameters:
params_out - Structure containing the results. There are 16 key names (one for each property map)
and for most of them 9 sub key values are calculated: total, mean, median, standard
deviation, skewness, kurtosis, min, and max.
Key names: usflx, sflux, gamma, hgradbt, hgradbz, hgradbh, jz, usiz, twistp, hz, ushz,
snetjzpp*, rhod, rho, sheargamma, ggt45fract**.
Sub-keys: total, ave, stddev, median, max, skewness, kurtosis.
*Only total sub-key.
**Only the fraction value, no sub-key.
Property name in DB:
sharp_kw.keyname.subkeyname
E.g.: sharp_kw.usflux.total For total unsigned flux.
Repository:
https://dev.flarecast.eu/stash/projects/FE/repos/sharp_kw-idl/browse