#
# u2d2.rb
#   $Id: u2d2.rb,v 1.2 2000/11/18 19:03:45 keiko Exp $
#


require "narray"
require "numru/dcl"
include NumRu
include Math


nx = 37
ny = 37
xmin = 0
xmax = 360
ymin = -90
ymax = 90
drad = PI / 180
p = NArray.sfloat(nx, ny)

#-- data ---
for j in 0..ny-1
  for i in 0..nx-1
    alon = (xmin + (xmax-xmin)*i/(nx-1)) * drad
    alat = (ymin + (ymax-ymin)*j/(ny-1)) * drad
    slat = sin(alat)
    p[i,j] = 3*sqrt(1-slat**2)*slat*cos(alon) - 0.5*(3*slat**2-1)
  end
end

#-- graph ---
iws = (ARGV[0] || (puts ' WORKSTATION ID (I)  ? ;'; DCL::sgpwsn; gets)).to_i
DCL::gropn iws

DCL::grfrm

DCL::grswnd(xmin, xmax, ymin, ymax)
DCL::grsvpt(0.2, 0.8, 0.2, 0.8)
DCL::grstrn(1)
DCL::grstrf

DCL::usdaxs
DCL::udlset('LABEL', false)
DCL::udlset('LDASH', false)
DCL::udiset('isolid', 2)    
DCL::udiset('icycle', 4)    
DCL::udcntr(p)

DCL::grcls