----- file created by makedoc on: Thu Sep 11 15:03:11 2014
----- Documentation for /scisoft/xop2.4/extensions/shadowvui/src/lib/getshcol.pro -----

 NAME:
	GETSHCOL
 PURPOSE:
	extract a column array(s) from a SHADOW file or structure.
 CATEGORY:
	SHADOW's utilities.
 CALLING SEQUENCE:
	output=getshcol(shadow_in,col,keyword_parameters)
 INPUTS:
	shadow_in   may be:
           a shadow file (between quotes) (e.g. 'begin.dat') or
           an IDL-SHADOW structure
	col    number of SHADOW column to extract or array with
		the SHADOW columns to extract.
           the colum meaning is the following:
           1   X spatial coordinate [user's unit]
           2   Y spatial coordinate [user's unit]
           3   Z spatial coordinate [user's unit]
           4   X' direction or divergence [rads]
           5   Y' direction or divergence [rads]
           6   Z' direction or divergence [rads]
           7   X component of the electromagnetic vector (s-polariz)
           8   Y component of the electromagnetic vector (s-polariz)
           9   Z component of the electromagnetic vector (s-polariz)
          10   Lost ray flag
          11   Energy [eV]
          12   Ray index
          13   Optical path length
          14   Phase (s-polarization)
          15   Phase (p-polarization)
          16   X component of the electromagnetic vector (p-polariz)
          17   Y component of the electromagnetic vector (p-polariz)
          18   Z component of the electromagnetic vector (p-polariz)
          19   Wavelength [A]
          20   R= SQRT(X^2+Y^2+Z^2)
          21   angle from Y axis
          22   the magnitude of the Electromagnetic vector
          23   |E|^2 (total intensity)
          24   total intensity for s-polarization
          25   total intensity for p-polarization
          26   K=2 pi/lambda [A^-1]
          27   Kx = K * col4 [A^-1]
          28   Ky = K * col5 [A^-1]
          29   Kx = K * col6 [A^-1]
          30   S0-stokes = |Es|^2 + |Ep|^2
          31   S1-stokes = |Es|^2 - |Ep|^2
          32   S2-stokes = 2 |Es| |Ep| cos(phase_s-phase_p)
          33   S3-stokes = 2 |Es| |Ep| sin(phase_s-phase_p)
          34   CohS      = |Es| sin(phase_s)
          35   CohP      = |Ep| sin(phase_p)
 KEYWORD PARAMETERS:
        NOLOST = consider losses
            0 all rays (default option)
            1 exclude losses;
            2 only losses;
        VERBOSE = flag passed to readsh
 OUTPUTS:
	an array with the extracted column(s)
 COMMON BLOCKS:
	None.
 SIDE EFFECTS:
	None.
 RESTRICTIONS:
	None.
 PROCEDURE:
	Straightforward.
 KNOWN BUGS:
	None.
 MODIFICATION HISTORY:
	M. Sanchez del Rio. ESRF. Grenoble, June 1995
	98-06-15 srio@esrf.fr fixes a bug when extracting an array of
		columns being Energy one of those. Cosmetics.
	06-02-21 srio@esrf.fr adds cols 19,26-29. Works in Double.
	2009-01-21 srio@esrf.eu adds verbose keyword.
	2010-11-26 srio@esrf.eu patches to return zero if no good rays found
	2013-05-30 srio@esrf.eu updated physical constant hc following shadow3

