This file is ment to be a PRIMER on the feature and use of this release of
  SGK's libraries. This release works under IDL 5.5, RSI lack of understanding
  of the concept of backward compatibility is out of my control :)

  It will be extended if there is interest in these libs, by adding examples
  provided by users.

  Note that they are ment to be used under a UN*X OS (use of /tmp and some
  other UN*X feature).

color/colormaps:

  My color maps are stored in the subdir colormaps/, and are loaded with the
  routines SGKLCT or XSGKLCT. The location of the color maps subdir can be
  specified thru the enviroment variable COLMAP_DIR

math:

misc:

plot:

  LABEL: [La]TeX alike parser for plot labels, ie:

       plot, ... , title = label('$\alpha_{1}^{"}$')

    list of symbols:

      \\ \AA \sqrt \| \alpha \beta \gamma \delta \epsilon \zeta \eta \theta
      \iota \kappa \lambda \mu \nu \xi \o \pi \rho \sigma \tau \upsilon \phi
      \chi \psi \omega \Gamma \Delta \Theta \Lambda \Xi \Pi \Sigma \Upsilon
      \Phi \Psi \Omega \pm \times \div \leq \geq \equiv \ll \gg \sim \neq
      \propto \leftarrow \downarrow \rightarrow \uparrow \ell \exists \nabla
      \infty \partial \int \Int \oint \plus \star \dot \diamond \triangle
      \cross \square \{ \} \_ \^ \$ \ \blank \~ \bs

  SWINDOW, STV, STVSCL, SXYOUTS, SPOSITION

   routines to get on a postscript plot what you got on the screen:

    image = randomu(seed, 200, 300)
    image = image*100+150
    swindow, 0, xsize=300, ysize=400
    stv, image, 50, 50  
    plot, findgen(10), /noerase, $
      position = sposition([50, 50, 250, 350]), /dev
    sxyouts, 100, 200, 'this is at (100,200)'

   the same commands inside a PS_OPEN and PS_CLOSE will produce a similar
   output, test this using: 
     ps_open, /portrait
   then these commands, then
     ps_close, /noprint
   and view the resulting /tmp/idl-<username>.ps with a PostScript viewer (gs,
   gv, ghostview, ...)

  SDSP: uses the above routines to display an image with a frame:

   image = randomu(seed,200,300)*100+150
   sdsp, image, zoom = [2, 1], xr = [-1, 1], yr = [0, 30]