(e2) Cartesian Projection of 3D Coordinates of Curvi-Linear Features

After you have done the stereoscopic height measurements of a set of curvilinear features (e.g., loops or filaments) you may want to visualize the 3D coordinates [x,y,z] of a set of loops in the three orthogonal projections, so in the [x,y], [y,z], and [z,x] planes. Let us suppose you have stored the coaligned images in the array IMAGE_PAIR(2, NX, NY) in a savefile="loop_A.sav" (see tutorial a2) and the 3D coordinates in the output loopfile="070509_D_trace.dat", you can generate a plot with the 3 orthogonal projections with the following commands:

IDL>
savefile='loop_A.sav'
loopfile ='070509_D_trace.dat' ;output filename where 3D coordinates of loops are stored
fov =[640,820,800,980] ;i1,j1,i2,j2 coordinates of field-of-view
ct =5 ;IDL color scale
hmax =0.1 ;e.g., hmax=0.1 solar radii (maximum height)
win =0 ;e.g., IDL window nr
restore,savefile ;restore saved data from step (2a)
euvi_projection3,fov,loopfile,para,ct,hmax,win

The output on the screen will look like this:



The three colors refer to tracings in the three wavelengths (171, 195, 284 A). You find also a color postscript file with the name 070509_D_pro3_col.ps