; sf_structure.pro: A structure, which holds a "Small angle"
;                   "fiber diagram"
;+
; NAME:        sf_structure
; PURPOSE:
;    Definition of a structured variable ("Record"),
;    which can hold a fiber diagram
; CATEGORY:
;    "Instance" generation
; CALLING SEQUENCE:
;    img = sf_structure( 'SAXS pattern', '19961001', 500, 450 )
;    generates an instance of the object sf_structure with
;      img.Title  = 'SAXS pattern'
;      img.Date   = '19961001'
;      img.Width  = 500
;      img.Height = 450
;      img.map    set all zero (Floating point 500 x 450 matrix)
;      img.BoxLen = ( 0, 0 ) (Floating point vector)
;      img.Center = ( 0, 0 ) (Integer vector)
;
;    img.BoxLen is for the box lengths of a pixel in x- and y-direction, resp. 
;    img.Center is for the center of the fiber pattern. The convention
;    is closely related to pv-wave examples: A center with
;                img.Center(0) = 244
;                img.Center(1) = 228
;    means, that the true center is at (x,y) with x=243.5 and y=227.5
; INPUT:
; OUTPUT:
; SIDE EFFECTS:
; RESTRICTIONS:
;    Be sure, that img.Title, img.Date, img.Width and img.Height are fed
;    with data of correct type (string, string, integer, integer )!
; PROCEDURE:
; AUTHOR:
;    Dr. Norbert Stribeck, Institute TMC,
;    University of Hamburg, Bundesstr. 45,
;    D-20146 Hamburg, Germany
;    stribeck@vxdesy.desy.de
; MODIFICATION HISTORY:
;-

;
FUNCTION sf_structure, name, stamp, x, y
;        ============
; Generate sf_structure and fill it with the parameter values
  RETURN, { , Width: x, Height: y, map: FLTARR(x,y), $
              BoxLen: FLTARR(2), Center: INTARR(2), $
              Title: name, Date: stamp }  
END ; Function sf_structure