;++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
;
;*NAME:                 grat_plot
;
;*CATEGORY:             instrument development tool
;
;*PURPOSE:              plot geometrical orientation of diffraction grating
;
;*CALLING SEQUENCE:     grat_plot, eta, alpha, blaze, [/FORWARD] 
;                                  [,UR][,LL=][,LR=]
;
;*PARAMETERS:
;              input:   eta     collimator/camera angle [degrees], float
;                       alpha   angle (grating normal,camera axis) [deg.], float
;                       blaze   grating blaze angle [degrees], float
;
;              output:  none
;
;   optional Keywords:  /FORWARD  flag, "forward" diffraction, m=+1
;                       UR=     string, Text in upper right corner
;                       LR=     string, Text in lower right corner
;                       LL=     string, Text in lower left corner
;
;*EXAMPLES:             grat_plot, 42.0, 12.4, 5.8, [/FORWARD]
;
;*SYSTEM VARIABLES USED:   none
;
;*COMMON BLOCKS:           none
;
;*INTERACTIVE INPUT:    none
;
;*SUBROUTINES CALLED:   rot_vect  
;
;*FILES USED:           none
;
;*SIDE EFFECTS:
;
;*RESTRICTIONS:
;
;*NOTES:
;
;*PROCEDURE:
;
;*MODIFICATION HISTORY:
grating_VERSION = 'grat_plot.pro Version 1.0 --- 27/05/02 mmr'
;
;	27/05/02	MMR	initial programming
;          
;*AUTHORS:
;
;	MMR		Martin M. Roth	Astrophysikalisches Institut Potsdam
;					An der Sternwarte 16
;					D-14547 Potsdam  
;					Tel. +49 - 331 - 7499 313
;                                       email: mmroth@aip.de
;-