Function Cosangle, u, v

;+
; NAME:
;	COSANGLE
; VERSION:
;	3.0
; PURPOSE:
;	Finds the Cosine of the angle between two vectors.
; CATEGORY:
;	Geometry, General.
; CALLING SEQUENCE:
;	Result = COSANGLE ( U, V)
; INPUTS:
;    U, V
;	Vectors, numeric, same length, otherwise arbitrary.
; OPTIONAL INPUT PARAMETERS:
;	None.
; KEYWORD PARAMETERS:
;	None.
; OUTPUTS:
;	Returns the Cosine of the angle between the two vectors.
; OPTIONAL OUTPUT PARAMETERS:
;	None.
; COMMON BLOCKS:
;	None.
; SIDE EFFECTS:
;	None.
; RESTRICTIONS:
;	Vectors must be non-zero.
; PROCEDURE:
;	Uses the functions FPU_FIX, VINP and VNORM from MIDL.
; MODIFICATION HISTORY:
;	Created 30-JUNE-1992 by Mati Meron.
;	Added to MIDL 10-NOV-1997 by Mati Meron.
;	Modified 10-SEP-1998 by Mati Meron.  Underflow filtering added.
;-

    on_error, 1

    return, FPU_fix(Vinp(u,v)/(Vnorm(u)*Vnorm(v)))
end