MPOLE

A suite of   programs implimenting the Minimum Current Corona model. Written by Dana Longcope

Help

http://solar.physics.montana.edu/dana/MCT_glossary.pdf - Dana's glossary on magnetic charges topology
http://solar.physics.montana.edu/dana/mpole/mpole_doc.html - MPOLE program documentation
http://solar.physics.montana.edu/dana/mpole/ - MPOLE

MOST OF THE COMMANDS USED BELOW ARE WELL DOCUMENTED ON THE MPOLE website 
http://solar.physics.montana.edu/dana/mpole/mpole_doc.html 

Sequence of commands 

When you did your tesselation as an output you got a mask structure saved inside the file=filename. 

Example:
    >restore,'ar000/lcthi1hr10gau.sav',/ver	   
    >lct2pns_adv,msk,/jpeg,/match,/flux,/discard,file='lctadv75',bthr=75,/reverse 
			  Output: lctadv75.pns
   	>save,msk,filename='mask75.sav'
   	>help,msk,/st
   	
After you have saved it you can use it in your future sessions.	
	>restore, 'mask75.sav',/ver

You can see the 0th element of your mask with
	>show_msk,msk[0],/lab,max=500.0
	
To calculate poles
	>pls=msk2pls(msk[0],view,/msk)
	
Plot locations of each pole in a pole structure
	>show_poles,pls,view=view,/mg
	
Try to find as many nulls as possible using a combination of reasonable initial guess locations.
	>nls=all_nulls(pls)
	
Graph the locations of sources, nulls and footprints of the field. 
	>show_fp,pls,nls
	
Display only part of the map
	>show_fp,pls,nls,xr=[-160,120],yr=[-140,100]
	
You can also calculate poles and nulls from the .pns file. 
Restore data from pns file
	>rd_parr,'lctadv75.pns',parr,view=varr
	>time=view2time(varr)
	>pls=parr[0]
	>view=varr[0]
	>nls=all_nulls(pls)
	>show_fp,pls,nls

To do overlay of topological map over TRACE image you need to get the TRACE data. 
You can find it online on http://trace.lmsal.com/trace_cat.html
Chose Trace fits-file you will use for the overlay
	>tr=trace_rd() 
	>help,tr,/st

Display the Trace fits-file. You could use different max values for different wavelengths. Sometimes you may get 
a better image display using alog10(tr.img) instead of tr.img.
	>display,tr.img,tr.x,tr.y,/aspect,max=300.0,tit=tr.date

Overplot topology
	>show_fp,pls,nls,view=view,/over	
	
Calculate separators
	>spr=all_seprs(pls,nls)
	>help,spr
	
Show separators with poles and nulls
	>show_sepr,pls,nls,spr
	
Calculate helicity.

The helicity codes are inside ~dana/flare13may2005 directory. The code marr_hel.pro can be
used to calculate braiding and spin helicity fluxes as explained in the following paper:
http://solar.physics.montana.edu/dana/pubs/LRB07.pdf
The commands to calculate helicity are the following
Copy helicity calculating functions inside your directory
	>$cp /home/dana/flare13may2005/mean_reg_vel.pro .
	>$cp /home/dana/flare13may2005/marr_hel.pro .
	>$cp /home/dana/flare13may2005/rel_hel_flux.pro .

Compile the copied programs
	>.compile mean_reg_vel.pro
	>.compile rel_hel_flux.pro
	>.compile marr_hel.pro

Restore sav file with a mask
	>restore, 'mask75.sav'

Calculate helicity using marr_hel(returns a structure containing the various helicities)
    >hel = marr_hel( msk, pad=200 )
    >rd_parr, 'lctadv75', parr, view=varr
    >pm = parr_model( parr, ifr=9, n=3 ) 
    >hparr = parr_helicity( pm, view=varr )
 	>plot, hel.time, hel.hel, yr=[-2.0e10, 1.0e10 ]
	>oplot, hel.time, hel.hel_sp, ps=1
	>oplot, hel.time, hel.hel_br_lct, ps=7
	>oplot, hel.time, hel.hel_br_lct+hel.hel_sp, ps=2
	>oplot, hel.time, hparr, lines=2? ? ? 

Plotted are (solid): H from the LCT velocity; (+) total spin helicity; (X) total braiding helicity; (*)
sum of those two; (dashed) the braiding helicity from the smoothed poles model.