IDL Software for analyzing shockwave images

Lane Roquemore took this data on a Phantom camera collaborating with Nirmol Podder, from Troy University.

Programs written in IDL are described below. The source for these routines can be found online, or on the PPPL Linux Cluster in $NSTXUSR/util/idl_cvs.

(For a list of some MPEGS of NSTX plasmas available from Phantom cameras, see: http://nstx.pppl.gov/nstx/Software/Diagnostics/Miro/.)

MPEG files can be created from the Cine files with cine2mpeg.pro . An example is Ne110us.mpg .

Combining the shockwave movies with different currents into one are available for Argon and for Nitrogen (Neon?). These were produced with shockcombine.pro .

Clickon7.pro is somewhat general purpose (it evolved from another use) and lets you play the .cin movie files like a VCR, save individual frames, plot values of columns or rows, adjust gamma, etc.

    IDL> clickon7

You will be prompted for a file to read. The input .cin files can be found in $NSTXUSR/phantom4/ and begin with GDArex or GDNex.

Sample images from clickon7:

[png]

And under the Special menu: [png]

shockvstime.pro stacks plots of a line from the center of .cin file image at various times

    IDL>  shockvstime, /edge, inc=3

It defaults to '$NSTXUSR/phantom4/GDArex20usFps43000DC50maP5.02tor12kV.cin'.

Sample image from shockvstime:

[png]

The colored diamonds are attempts to find the leading edge of the shockwave.

Here is another way to look at shockwaves:

[png]

An artificial surface has been generated with time increasing away from the axes.

Edited on 18-Sep-2008 by Bill Davis , PPPL.