Halftone - is a utility for drawing half-tone pictures in which the gray scale level is proportional to

       To use EZHFTN or HAFTON, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c, preferably in
       that order.

       Copyright (C) 1987-2009
       University Corporation for Atmospheric Research
       The use of this Software is governed by a License Agreement.

UNIX                                               March 1993                                   Halftone(3NCARG)

       Halftone - is a utility for drawing half-tone pictures in which the gray scale level is proportional to
       the value in a two dimensional array.

       Online: hafton, ezhftn, halftone_params, conpack, conpack_params, cpcica

       Hardcopy: NCAR Graphics Contouring and Mapping Tutorial; NCAR Graphics Fundamentals, UNIX Version; User's
       Guide for NCAR GKS-0A Graphics

       Halftone is obsolete.  It has been replaced by the CPCICA entry of the Conpack contouring package.

       Halftone continues to be provided for compatibility of early NCAR Graphics codes.  If you are writing new
       code, we suggest that you use CPCICA.

       EZHFTN(Z,M,N) - draws a half-tone picture based upon a set of default options.
       HAFTON (Z,L,M,N,FLO,HI,NLEV,NOPT,NPRM,ISPV,SPVAL) - Draws a half-tone picture from data stored in a
       rectangular array with the intensity in the picture proportional to the data value.