Polarity inversion line identification from SDO magnetogram

Nearest neighbor pixels analyzer which is based on the cellular automata approach.

Description

An efficient algorithm for identification of strong polarity-inversion line (SPIL) on Solar Dynamic Observatory (SDO) Helioseismic and Magnetic Imager (HMI) magnetograms.

Detailed description will appear in the paper: Volobuev, D.M. Strong
Polarity-Inversion Line Preceding X-class Flare, Solar Physics, 2011
Initial data (65 megabyte .fits magnetograms) can be downloaded from http://hmi.stanford.edu/

- SdoPIL.m script - calculates example of SPIL with 100 Gauss threshold. Threshold can changed in the script text.

- select_dipoles.m function - marks SPIL pixels

- fill_fire_zp.m and fill_fire.zn functions - do iteration for region growing of SPIL to high magnetic flux (center of sunspot)

• Required Products: Optimization Toolbox
• MATLAB release: MATLAB 7.10 (2010a)