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drawNDCGrid

Draws NDC grid lines at 0.1 NDC coordinate intervals and labels them.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/shea_util.ncl"

	procedure drawNDCGrid (
		wks  : graphic   
	)

Arguments

wks

A Workstation identifier. The identifier is one returned either from calling gsn_open_wks or calling create to create a Workstation object.

Description

This procedure draws NDC grid lines at 0.1 NDC coordinate intervals and labels them. This procedure is useful to help determine placement of labels and lines on plots when using functions like gsn_add_text.

The frame is not advanced in this procedure.

Examples

Example 1

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl" 
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl" 
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/shea_util.ncl"

begin
  f      = addfile ("80.nc", "r")
  x      = f->U(0,17,:,:)       ; Grab first timestep, 17th sigma level 

  wks = gsn_open_wks("ps","test")
  res                     = True
  res@gsnFrame = False
  plot = gsn_csm_contour_map_ce(wks,x,res)                                           
  drawNDCGrid(wks)
  txres = True
  txres@txFontHeightF = 0.015
  gsn_text_ndc(wks,"Now I can exactly place the text where I want it to be!",0.5,0.2,txres)
  frame(wks)       ; The above text will be centered at .5 X NDC coordinate (middle of the page), 
                   ; and .2 Y NDC coordinate (near bottom of the page)                                 
end                                                   

For an application example, see:

• "text_3.ncl" (view example)